Firearm

Nothing like the smell of burnt powder in the morning

About twelve hundred years ago in China, some people figured out that certain chemicals mixed together (such as potassium nitrate, carbon, and sulphur) rapidly combusted when brought to spark, which became known as "black powder." After some experimentation, they discovered that a tube sealed off at one end could be used to contain the pressure of said combustion and focus it into an explosion to propel an object at high speeds. After a few centuries of refinement, and invention of the frag grenade, they managed to take that mechanical principle and apply it as a weapon of warfare which changed the game: the arquebus. Comparatively cheap, easy to make, easy to learn to use, and capable of penetrating all but the heaviest armor, this marked a transition away from close quarters to ranged warfare.

In modern times, firearms are the staple weapons of any nation. Speculative fiction showcases weapons that don't even fire solid projectiles, like lasers.

From an engineering standpoint, firearms had a big difference from previous weapons in that they don't require the user's muscle power to work. Swords, maces, and axes are swung, spears are thrust, and bowstrings need to be drawn. Even crossbows and siege weapons work by storing muscle power via tension until it's released. The energy required to accelerate a firearm's projectile comes from explosive propellants; all the user needs to do is to hold the weapon, aim, brace themselves and set off said explosive charge. The significance of this is illustrated in the American Proverb: "God made man, Sam Colt (the inventor of the first practical revolver) made them equal." Having a reliable repeating gun means that your simple brute physical strength does not mean as much in a fight as it would in a bare knuckle brawl or a swordfight (either defensively or offensively).

The firearm's bigger bro is the Cannon and its cousin is the Rocket.

How Traditional Guns Work

For our non-firearm oriented friends, here's a brief, heavily condensed explanation of how these murdersticks work. These instructions will probably vary depending on the type of gun you're using.

Some Tanegashima matchlocks

Olden Muzzle-Loading Guns

The Slow Way

1. Put your musket in half-cock position. Take your powder flask, and pour a few grains into the flashpan. Pour some more down the barrel (amount can vary wildly; later powder flasks come with built-in measuring tools for ease of use and safety). Ram the powder, bullet, and cloth wad down the barrel of your gun. Ensure you're doing this in correct order because putting the ball first, then powder, for example, can lead to hilarious and/or lethal results.
2. If you're using a matchlock gun: light up the fuse, aim and brace yourself, and lastly wait for the fuse to burn out. If you're using a flintlock gun: just cock the mechanism. With percussion caps, replace the explosive cap on the firing titty after cocking the hammer. In any case, aim once you're done setting it up.
3. Once the powder burns; the gasses from explosion of the black powder will send the bullet flying out of the barrel like a bat out of hell and penetrate into something or someone, and if you're lucky it might actually hit what you were aiming at. Also, hope you aren't downwind because guns during this time generated a lot of black smoke.
4. Take stock of the situation. If you've managed to hit anyone or you're currently still in a shooting war; repeat step 1. If your firing line missed most of their shots and those barbarians are charging up your position; affix bayonets. Additionally, if you have time, make sure to use the ramming rod to clean out the barrels of residue to avoid an explosive jam that could burst your barrel (said note applies to all guns unless you're using smokeless powder).

The Not-Quite-As-Slow Way

1. Take your paper cartridge, and bite off the end with the powder in it. Carefully pour a few grains into the flashpan, and the rest down the barrel. Take the remainder of the cartridge, ball and paper, and ram it down the barrel.
2. Follow steps 2 through 4 as above. Paper cartridges have the advantage of saving you a few seconds of precious time while reloading, which can mean the difference between life and death on the battlefield. Another advantage is that they can be made somewhat weatherproof with a grease coating. But if you're just hunting or can't find/afford paper, most people didn't bother with the time-consuming preparations. Towards the end of the muzzle-loading era, paper cartridges could be chemically treated to be more flammable, so tearing them open became unnecessary. This was mostly done with revolvers.

Single-Action Guns

1. Load rounds into the magazine (or chamber if it's a single cartridge gun), remove the safety, work the action (pump the slide, rack the bolt, cock the hammer, et cetera) to chamber a round, and aim.
2. Pull the trigger, this will cause the hammer to strike the primer on the chambered round and cause the powder inside the shell casing to ignite and explode; sending high-pressure gases screaming out of the barrel while propelling the solid bullet out at high speed towards whatever you were aiming at. If you're using single-action flintlock guns; see above for the result.
3. Because the gun lacks a mechanism to re-chamber itself; you now have to work the action again to eject the spent shell (unless its a revolver, in which case you do that while reloading) and load another round into the chamber. How you do this depends on the gun in question.
4. Repeat until you run out of bullets in the magazine if your gun has one or you have a spare moment where nobody's shooting at you, in which case either reload the magazine or load a new round (the default case if you're using a single round breechloader).

Auto-Loading Guns

1. Load rounds into the magazine, remove the safety, work the action to chamber a round, and aim.
2. Pull the trigger and this causes the same effect as stated above.
3. Because of the mechanism of the gun; it redirects some of the forces used to propel the bullet to work its action, eject the spent shell (unless its a DA revolver), re-chamber another round, and allow you to shoot again by just pulling the trigger. The forces used depend on the gun in question, some use a gas block or piston to redirect some of the gasses expelled by bullets, while other uses the force of the recoil itself, to work the action and chamber another round. Additionally, it could also re-chamber itself using a mechanical sequence (like revolvers) or is electrically operated.
4. If you're using an automatic; hold the trigger down and only release it once you want to stop shooting (or are forced to do so due to lack of ammo). If you're using a semi-automatic; pull the trigger again to fire another round.
5. Repeat until you run out of bullets or you have a spare moment where nobody's shooting at you, in which case either reload the magazine or load a new one.

A Brief History of Firearms

800's: Taoist monks attempting to find an elixir of immortality stumbled on the next best thing: a substance that would suddenly and violently make things very dead. They'd discovered potassium nitrate (alternatively called saltpeter), a white crystalline powder that burned with a purple flame. When mixed with powders of charcoal and sulfur the resulting substance would burn instantly and aggressively on exposure to flame. It didn't take long for the Chinese to start inventing ways to use it.

The Firelance, the Chinese invention that started this all

1000s to 1200s: The Chinese realize they can make barbarians shit their pants by shooting hollowed arrows packed with powder and bamboo tubes filled with powder and pebbles at them. Bamboo gradually gives way to cast iron and bronze. The Mongol Invasion accelerated the development as the Song Government tried everything to fight them off, which the Mongols often stole and used themselves.

1300s: Various gunpowder weapons begin to proliferate westward along the Silk Road, aided by the Mongols. Crude versions of hand cannons, grenades, rockets, and flamethrowers all see use. Despite considerable psychological effect and good armor penetration, most of these weapons are only marginally more likely to kill the target than the user and had a range of only twenty or so meters. As such, their use is not widespread. For the most part, these weapons were used by skirmishers and guards. The fact that they were so dangerous meant they were mostly used by low class soldiers, and in turn this meant that the smiths making them were generally not the most skilled artisans; which did little to improve quality even given the limitations of the day. Even so, the designs and methods of manufacture were gradually refined and improved by various early gunsmiths through trial and error if nothing else.

1400s: Hand cannons see continued and expanded use. Bit by bit from the crude handgonnes of previous centuries, the first "true" firearms evolve with the gradual development of the matchlock, taking on the basic shape of lock, stock, trigger, and barrel (which is where we get the saying from). By clamping a lighted wick into a flashpan via a trigger, the shooter is able to aim and fire at the same time, making him markedly less likely to blow his own jimmies off. Despite advances, the matchlock was unwieldy, unreliable, and generally inferior to a good bowman. The issue of course is that only England (in Europe) HAD good bowmen; bowmen were the scum of the army everywhere else. This didn't stop some inventive commanders from seeing their potential, particularly with poorly trained conscript soldiers. Some forces made a go of it by carrying two or three guns at a time and just throwing the spent ones away like a really shitty Matrix movie. Note: while we use a "weeaboo" hyperlink up there, it's worth remembering that troops like cuirassiers and even pirates would do the same thing with pistols, carrying a whole brace of them, but they just did not exist yet. By the 1400's having more then one gun was the only way to have any real rate of fire before breechloaders existed.

1500s: Guns continue to evolve with the invention of spring-loaded firing mechanisms. The wheel-lock spins a steel plate against sulfide rocks to produce sparks (think cigarette lighters), which ignites powder a flash pan. This was revolutionary, allowing soldiers to prime their weapon in a matter of seconds instead of fucking around with a lit wick, and allowed calvary to use guns for the first time while on horseback, giving rise to the cuirassiers. It also means that for the first time, guns weren't completely fucked in the rain, just mostly fucked. They also cost a lot to make and were still not completely reliable, so most people stuck with matchlocks. Powder formulas had improved considerably, including the development of the more powerful, stable, and moisture-resistant corned powder made by wetting raw gunpowder, forming it into corn kernel-sized cakes, crushing them, and sieving them for size. Japan's Oda Nobunaga was particularly notable in the history of firearms for his heavy transition from blades to guns after discovering the novelty of matchlock guns. In fact, by the end of the 1500s, they had more trained arquebusiers in their armies and produced more matchlocks than any other country to date during that period and had the most guns per capita in the world. They still relied on yari equipped pikemen to keep cavalry away but by this time, mounted archery and swordsmen had taken a backseat as supporting units like the knights and winged hussars in Europe. Meanwhile, virtually every army figured out how to use a combination of volley fire in dense square formations surrounded by pikemen (called Pike and Shot) or roughly equivalent units of gunmen protected by spearmen (such as the Chinese Mandarin Duck platoon formations); making armored cavalry, crossbows, & longbows outdated. Accuracy still sucked but that was what the massed shooting was meant to compensate for and soldiers were trained to just point their matchlock in the vague direction of the enemy en masse and fire.

The flintlock mechanism. Now you did not need to light some string and put it into a serpentine before firing

1600s The wheellock is refined into the simpler and more reliable flintlock, though it would take some time to supersede the matchlock. Muzzle loading is simplified with the creation of paper cartridges, essentially the pre-measured cake mix of murder. Some German dudes came up with the idea of cutting spirals into the barrel, which they called "rifling," to spin-stabilize the bullet so that they wouldn't have to walk up right next to their targets to hit them, but this required a barrel tighter than a nun's cunt, a hammer to ram the ball in, and grooved bullets made for the gun so it could fit the rifling of the gun like the cap to a soda bottle. To put all that into perspective: well-trained musketeers could fire three to four shots a minute, while a rifleman could only manage one shot every minute. Not great, however the idea of spin-stabilisation hung around and payed off in later times. Breechloaders are invented alongside the flintlock in both Europe and China but the problem of hot gas leaking and burning shooters' hands made them limited in use and in number. Hence, while nobles such as King Henry could own a breech loading rifle for hunting ducks, said breech loaders were either expensive to make in good quality, leaked hot gas every time you shot a less finely crafted piece, or was of inferior performance to the basic muzzleloader.

1700s: The French invent the bayonet, allowing their troops to be choppy while they were shooty. Thus, the Pike and Shot formation became the Bayonet and Shot formation. That and refinement of tactics led to the dense but slow and cumbersome square formations being reformed into thinner but more responsive rectangle formations. This is the point where gun infantry tactics become the dominant (though still not only) form of fighting when guns go from one of a few common infantry weapons to the primary weapon used by most infantry. Formations of musketeers go from big square blocks to lines two or three ranks thick to put enough bullets in the enemy's ranks as quickly as possible. In the 1600's armies had started to realize that dividing up your people into groups and firing in turn would allow you to maintain fire while reloading (particularly the English with the New Model Army), but it was in the 1700's that everyone really got good at drilling it into soldiers how to fight in lines. Another interesting development at this time was the creation of the air gun. As seen with the Italian Girardoni air rifle, it was issued to specialized sharpshooters who valued it's silence, long range, and rapid-firing capabilities. Their apparent effectiveness in the Austrian Army's Windbüchse Jägers during the Napoleonic Wars was such that according to legend (which is disputed by historians), Bonaparte himself was so angry that he desired for any soldier captured from those units to be hanged as assassins or spies instead of treated as a regular POW. However, the difficulties of making and maintaining reliable pressure tanks and air pumps meant it couldn't compete or become mainstream once conventional rifles and breechloaders were improved upon.

The mechanism of a French Chassepot needle rifle, an early bolt action rifle, as well as its paper cartridge

1800s: Pretty much everything that makes up a modern firearm is invented here. Some English fools discovered fulminates (with the first formula of mercury fulminate made from mercury, nitric acid, and ethanol), an unstable explosive compound that could be put in a metal cap that would instantly ignite if you slam it with a hammer; which led to the first explosive primers. So flintlocks transitioned to percussion caps. This basically involves putting explosives in your explosives to explode your explosives. Eventually, standardized methods of making copper & later brass casings by the French and English replaced paper cartridges; making gas leakage in breech loading mechanisms a thing of the past. Cartridges that contain a primer, propellant, and slug, similar to modern-day bullets, are developed. With this, not only was loading ammunition simplified with a package that contained everything needed for a gun to fire, it also made it waterproof & easier for conscripts to load. Furthermore, the brass casings' small expansion when firing served to seal the firing chamber to prevent hot gases from leaking and burning users’ hands. Extracting the flush but stuck cartridge in the chamber was simply a matter of adding extraction pins that were manually pressed to kick them out by the rims on the bottom base. By this time, wars were largely fought using firearms rather than melee weapons, though also by this time firearms were also melee weapons as in the early 1800s the bayonet charge was still both an accepted and useful tactic.

By the late 1800 inventors had finally gotten the technology to contain the force of the gunpowder explosion with a tight seal and do so cheaply. Experiments that had been done earlier like the Puckle gun (1718), Ferguson rifle (1776), and even the bizarre 1780 Girandoni Air Rifle, which was an air gun with a 20 round magazine, all failed to create breech loading rifles cheaply. See, despite that it was well known that that slotting in bullets from the rear and using a mechanism to load it into the chamber is much simpler than spending about half a minute to ram it down a long barrel, the technology was just not there as without cheap steel with good quality control (cheap is important for hand guns you are going to mass-produce). In the meantime, getting regular iron to contain the explosion without deforming, cracking, and leaking gas - thus weakening the shot - was a nightmare. The Industrial Revolution, among other things, gave birth to the ability to mass produce novelty features such as "breech-loading" and later "magazines" and simpler mechanised feeding systems like tubes, slides, cylinders, and bolt-actions. The likes of pump-action shotguns, bolt-action rifles, and lever-action rifles, and revolver and semi-automatic pistols, are developed and/or developed upon, giving a glimpse on how weapons in the future would function. Near the end of the decade, some French guys worked out that they could both improve firepower and keep their guns considerably cleaner by replacing black powder with nitrocellulose, the base component of most "smokeless powders." Also known as “guncotton/flash-paper,” it was first discovered by some German chemist who accidentally soaked a cotton apron in a nitric/sulfuric acid mix before trying to dry it by the fire; culminating with explosive results. After various explosive bouts of trial and error, the French managed to alter its formula to make it stable enough to use without blowing up its creators. They stabilized it by soaking and drying it a second time in alcohol. Next, they added stabilizer compounds that made the concoction safe to make without blowing factories sky high from static electricity. This alongside partly dissolving it in ether/alcohol to form collodion before adding extra explosive compounds such as nitroglycerin served to make it more malleable and explosive for shells and artillery. Shaping it was simply a matter of spinning/rolling it into stiff thread/yarn or sheets to be cut down to desired pellet/flake sizes. Not only is there a massive increase in power, its also a clean burn compared to the highly corrosive nature of black power and the horrible maintenance pain that comes with that. This won't matter as much for another century, since the primers are still corrosive.

Just as important as the new designs that came about during this period were the new methods of production. People like Eli Whitney worked out devices such as milling machines, which allowed for the quick production of finely tuned parts which were so close in size that you could take one bit off one gun, stick it on another from the same line, and it would work just as fine. Breech loading and repeating firearms had existed for centuries beforehand, but were not cost effective to mass-produce until the Industrial Revolution.

A British Lee-Enfield Bolt Action Repeating rifle

This is also the time where the first "automatic" guns were invented and put into production. The word "automatic" is in quotes because these early machine guns were not self-reciprocating; they did not load and fire themselves and were instead manually powered. The most famous (and successful) of these weapons is the Gatling gun, which saw limited action in the American Civil War, but became much more widely used the world over in subsequent wars. But while it was the most famous, the Gatling was not the only manual machine gun developed; dozens of different types were produced during the US Civil War alone on both sides, but because these guns tended to be mounted on cannon carriages they were treated like cannons instead of the close support weapon machines guns are, so it took some time for them to hit their stride. Some were hooked up to a motor and became true machine guns, giving them a rate of fire that's high even by today's standards, but the requirement of having a power source meant it only saw limited use on ships.

The first works of the great John Moses Browning start showing up. While his 20th century inventions are more famous, his perfection of the lever action, and invention of the pump action shotgun were major advances. Browning would even patent a semi-automatic shotgun by the end of the 19th century, though it would not be produced till the 20th.

1900-early 1930s: The heyday of guns because of the advent of WW1. The idea of bolt-action rifles are popularized, along with semi-automatic and fully-automatic weapons. Bolt-action rifles meant that riflemen no longer had to be confined to shooting one round at a time before needing to reload as they could now load individual clips that contained 5-10 rounds a piece. Machine guns are now becoming more and more popular in the battlefields, drastically changing the way infantry would maneuver the battlefield as a single MG emplacement can effectively cripple platoons with the right positioning. Submachine guns are developed by the Italians through total accident, as it turned out their pistol caliber machine gun designed for air-to-air fighting (remember planes of this era were very fragile) was effective as an infantry weapon. The German Empire would be the first to make a purpose built infantry sub-machine gun, giving the rest of the world an idea of the wonders of a lightweight fully-automatic weapon that could easily be used by infantrymen, which was previously restricted to crew-served heavy machine guns and the still heavy BAR. They were so impressive, the various post-war regulations prohibited the Germans from having a military armed with them (completely missing the loophole that the Germans could just arm civilians like police and railway guards with them and have a German owned company in Switzerland build them).

On the subject of the machine guns, if there was ever a weapon that represented this part of history it would be the heavy machine gun. We talked about the hand powered machine guns above, and while good when used correctly, these weapons have their issues. In order to use most of them, you had to be standing up to turn the crank and sustained fire was tiring, but the hand cranked guns had one major advantage: the most successful of the hand-cranked guns, like the Gatling or Gardner, had multiple barrels meaning you can fire them with little or no need to stop to let the barrels cool down. At the dawn of the 20th century, this is what the early machine guns had to be compared to when European generals went window shopping. The solution was water-cooling, which allowed machine guns to fire for countless hours with little or no failures, but at the cost of weight rendering them truly static, though highly effective, weapons. If you could point to two developments that caused the First World War's trench warfare, you can point to water-cooled machine guns and barbed wire.

The semi-automatic pistol had some developments in the last decade of the 19th century, but only the bulky C96 Mauser would see any real popularity, with next most notable, the Borchardt C-93, only having a few thousand made. The Borchardt’s refinement by Georg Luger would be one of the big game changers, as it saw adoption by the Swiss in 1900 and Germany in 1904. John Moses Browning would be the real pioneer, creating a series of pocket pistols that saw widespread success in civilian sales. He would cap this off with the 1911 in the same year, his first military pistol that was then adopted by the US military. He designed the 1935 Browning Hi-Power, but didn’t live to see it completed by his apprentice Dieudonné Saive and his son Val Browning. The pistol was produced by both sides of World War II (its factory was captured when Belgium was invaded, but Saive would flee with the plans and produce them in Canada), and all future developments amounted to more plastic, and a few improvements to safeties. All the mainstream self-loading pistol cartridges that remain in use are from this era except for 9x18 Makarov (unique more to deny captured pistols ammo than effectiveness), .40 S&W (never adopted by a military and rapidly falling out of favor after its main user decided to go back to 9mm), and some rounds intended to defeat body armor that aren’t primarily for pistols anyways.

late 1930s-1940s: At the start of World War II, all of the powers involved, France, England, Germany, and Russia, were armed with bolt action weapons. Over the course of the war, automatic and semi-automatic rifles started to become more common; however, only the Americans completely phased out bolt-action rifles for standard infantry by the time of the war (Marines and Army units in the Pacific Front were stuck with the old stuff for a few months due to the Germany First policy). Submachine guns are now becoming more popular with various armies around the world, making it the staple lightweight automatic weapon for infantry troops, totally redefining urban combat due to the weapon's great effectiveness in close combat. Nazi Germany invents the Sturmgewehr 44, the first widely produced assault rifle (the Fedorov Avtomat was the first to be put into service, introduced in 1915, but production was limited due to costs and uh, well...). This weapon would later become the template for modern assault rifles used by the world over.

A QBZ-95 Assault Rifle, the current service rifle of the People's Republic of China, note bullpup configuration (the magazine feeds behind the trigger), thus saving space

One unsung advance is the production side. Advances in manufacturing phase out final hand-fitting (that the 1911 and M1 Garand predate this is why current production still varies and costs so much). The M1 Carbine, due to extensive efforts by the US military, it was the first firearm to have all parts be completely interchangeable, no matter which factory it was made in.

1950s-1990s: With World War II over, the armies of the world had a chance to study Germany's assault rifle and built their own. The key invention was selective fire, which allowed a single weapon to serve as a traditional rifle or a somewhat long and unwieldy submachine gun. Burst fire was also developed, intended to fire a grouping of rounds to defeat personal body armor but automatically stop before the recoil of fully automatic fire would have a significant impact on aim. The USSR's entry was the AK-47, which was powerful, easy to mass produce, and legendarily tolerant of mistreatment after briefly flirting with the SKS (a semiautomatic carbine fed by stripper clips). On the other side of the world, the US briefly experimented with an automatic version of the M1 known as the M14, before (mostly) getting their shit together and developing the M16, which was expensive, complicated, and notoriously finicky. One thing not to be underestimated is the standardization introduced by NATO and the Warsaw Pact. Gone were incompatible calibers unique to each nation, and in their place were a single pistol caliber (9x19 for NATO, unless you were an American snowflake, and 9x18 for Pact.), a single intermediate caliber (5.56x45 for NATO, 7.62x39 for Pact, later 5.45x39 in certain Pact countries), a single full power rifle cartridge (7.62x51 for NATO, unless you were a French snowflake, and the venerable 7.62x54 for Pact), and heavy machine gun cartridge (.50 BMG for NATO and 12.7×108mm for Pact) for small arms. Even before NATO standardization was officially a thing, many western countries eagerly armed themselves with American surplus M1 Garands and M1 Carbines, which greatly simplified things.

2000s: With the invention of more advanced materials such as plastics and carbon fiber, along with numerous technological advancements of the modern world, firearms are... basically the same they've been for the last fifty years, just usually lighter and with more options. Serious efforts were made to look at new designs like caseless ammo and fused smart grenade bullets, but most went nowhere. The most significant development in firearm technology was the advent of practical ranged tasers; essentially wired dart launchers with high voltage capacitors, they're the first handguns ostensibly intended for less lethal force (occasional heart attacks not withstanding) that weren't a total joke (like pistol caliber tear gas rounds).

2010s: Relatively speaking, guns have changed a lot and a little in the following years. Primarily, there had been emphasis placed on modularity, mobility, and ruggedness as can be seen with Western nations adoption firearms such as HK416 variants or overall improving the current M4 system. Development of practical telescopic and caseless ammo (LSAT program), and ship cannon sized railguns (The Naval Research Laboratory) have been placed, with the former showing fruition into the NGSW program (see 2020s). The main innovation at this time comes from the improvement of optics, machining techniques (such as CNC machining), materials (stronger and lighter polymers as well as overall better metal alloys), and further optimized design. New designer rounds have been developed to compete with conventional military ammunition, however by late 2019 most have fallen into either becoming niche or have lost traction/attention for wider spread use. Thus in 2010s the firearm technology focus was improving and fine tuning current technologies with some developments into more experimental areas.

Further development of practical telescopic ammo. Designed to be provide reduce weight not not compromising muzzle energy. Culminated into the NGSW program

On the more individual front, CNC and 3D printing development has improved significantly enough that either personally designed or online sourced designs can be used to produce firearms parts and associated equipment that can be used to quintessentially make home made firearms. Although several nations have tried to curb this onset of what have come to be called ghost guns, this phenomenon is here to stay. On a larger scale production front, CNC firearms manufacturing allows for more precise machining thus superior fit and finish and improved tolerances.

NGSW system prototypes by different companies competing for the potential to become America's new service rifle. The last one is the winner.

2020s: With the rising commonality of rifle resistant gear (i.e. body armor and helmets, eg not unheard of for soldiers to survive otherwise direct fatal blows thanks to modern helmets), need for reduction of weight and increased mobility, ability to react to both close and extended range threats (eg M4A1/M27 accurately pushes to 500/600 meters where engagement ranges can exceed 800 meters), and desire to overmatch competing militaries, Western firearms development has begun to focus on new munitions. Namely looking to full power and reduced weight ammunition (be it polymer or reinforced) that can reach out lengthy distance without being excessively heavy or cumbersome. In that regards, the US Army is looking into the NGSW system program, with several contractors competing for the program. Thus far the competition as of 2020 consists of AAI Textron Systems (backed H&K & Winchester), General Dynamics, and SIG Sauer competing for the bid.

Currently the US Military and its branches are looking at 6.8mm NGSW (no XM designation yet), 6.5mm Creedmoor, and .338 Lapua/Norma Magnum to either replace or supplement current ammunition such as 5.56 and 7.62 NATO. The latter most more so because American snipers found themselves outmatched by their European counterparts. Come April 2022 and the Sig Sauer candidate has been declared the winner. While sporting a conventional layout and using standard brass ammunition (with a stainless steel tail to contain the pressure), it’ll likely get the job done and will be issued to infantry, scout, and combat engineer units in the Army while everyone else will keep the M4 until further notice. Or they'll just do another competition to get an actual caseless round to replace everything and have XM5's be used by line units until then.

As of 2022 if you have 3,500 dollars you, yes YOU can buy a working Gauss rifle. While definitely out of the reach of most armed forces for mass deployment, it took less then 1 human life time to go from the Wright Brothers to the heavy multi-engine bombers of WWII so the technology is coming.

GUN SAFETY

Should be self-evident, but to be frank it isn't. Between the movies having actors brandishing guns everywhere, the video games and toys like airsoft that make them look more harmless than they are and plain human ignorance and negligence; people forget that they're holding something that could easily scatter someone's brains or outright remove their skull.

That said, there are four main rules to gun safety.

• Muzzle sweep: Avoid this. Muzzle sweep is one when points or sweeps a gun in a direction onto people or objects that could get harmed. To avoid this, one should keep the gun's barrel pointed away from anything that you don't intend to destroy or value. This means one must be conscious of where they are pointing it. Or in other words, never point the gun at something you don't want to shoot!

• Treat every firearm as if they were loaded at all times. Even if you fully know the gun is empty after removing the magazine and checking the chamber, still treat it as if it wasn't. This creates a force of habit so that if you are ever in a rush/interrupted while handling your gun/given a weapon by someone else/whatever... you will avoid any mishaps and tragedies that could arise because you think the gun is empty where it actually isn't. The only obvious exception is during maintenance, and that's only after visually and physically ensuring the chamber is clear and the magazine is removed (or empty if your gun's magazine is built-in). Don't feel peer pressure to stop obsessively checking each and every chamber around. As far as addictions go, this is not a bad one. Always, always check multiple times. If you don't feel sure for a single moment, check it. Better to waste a couple of seconds loading a magazine, cocking a round, or disengaging the safety features than risking a life from impatient carelessness. Just ask Alec Baldwin.

• Know the target, what's in front of the target, and what's behind the target. Remember, bullets are designed to punch holes in things. Even if you've got pinpoint accuracy, the bullet might go right through the target and kill some guy who's just minding his own business. This is why any self-respecting firing range has a thick wall or a pile of packed-down dirt behind the targets. Bullets that don't punch through the target and don't shatter (like frangible rounds made of sintered metal) can ricochet back at the shooter or others around them. For this reason, shooting at metal targets is usually done with the targets angled down. And loudly letting people know when you’re going to fire a gun reduces the risk of idiots somehow getting in between the target and the shooter.

• Trigger discipline: Never put your finger on the trigger unless you want to kill/destroy whatever you're pointing your gun at. Why? Any number of things, either in a firefight or peaceful day in the gun range, can cause you to be spooked and involuntary clench your fingers. If your finger happens to be on the trigger of a live gun, you can potentially cause a negligent discharge, and that's bad. As in "You're putting your and other people's lives at great risk for being a colossal idiot" bad. It doesn't matter if you're a hardcore Tier 1 spec ops operator or regular Joe taking on recreational backyard shooting, everyone's susceptible to the dreaded ND, which is why it should be second nature for you to always keep your finger off the trigger until ready to fire.

Easy, right? Well... apparently not. Ask any gun enthusiast and they'll gladly tell you all sorts of horror stories that happened because somebody failed to follow these simple rules.

And for the love of the God-Emperor, don't be a fucking tool and mix alcohol/drugs and firearms together. Doing so, very, very unsurprisingly results in the breaking of one or more of the aforementioned rules.

Types of firearms

Having been around for well over 1500 years there have been many types of firearms over the course of time. Humans are, if anything, very inventive when it comes to coming up with new and interesting ways to kill each other. A rough list are:

Ye Olde Gonnes

• Firelance: Oldest of the Oldschool guns, simple bamboo tubes stuffed with gunpowder and pebbles used in the Ten Kingdoms period and the Song Dynasty. One inaccurate spray of flaming fuck-off in close quarters, often tied to a spear.

• Handgonne: A catch-all term for a primitive gun without a lock that need their powder charges. Majority of these guns were handcannons, as in literal man-portable artillery pieces that had a 50/50 chance of either working or malfunctioning, the worst of which would be the gun exploding in the shooter's face.

• Arquebus - A basic matchlock Firearm. A note of clarification: 'Arquebus' and 'musket' are both used to describe firearms from this time and they are often used interchangeably. But if you want to be really technical in this period an Arquebus is a regular two handed matchlock firearm while a musket is a larger heavier gun firing a larger projectile, sometimes up to an inch in diameter. Latter (about 1700 onward) musket would refer to any muzzleloading long barreled handheld firearm used for mainly shooting solid shots. This is not too much of a big deal and is nothing to get mad about, but it is worth noting.

• Musket - Today, the musket is a catch-all term for all early smoothbore, shoulder-fired, muzzle-loaded firearms. Technically this isn't the case, the musket was an improved Arquebus, one of the earliest muzzle-loaded guns. However because of romanticism and literature; people who aren't acquainted with firearms will commonly refer to any muzzle-loaded long weapon as a musket (about the same reason why most people today refer to any automatic weapon as a machine gun). Muskets were inaccurate as people have yet to put serious research into firearm ballistics, lacked sights, generated a lot of smoke due to primitive gunpowder mixtures, and were temperamental to environmental conditions (rain will pretty much render a musket into an wet stick of wood), but still enjoyed a lot of popularity due to their lethality and ease of use compared to other man-portable ranged weapons at the time - and even their inaccuracy (they were after all, shooting at a bunch of guys standing shoulder-to-shoulder...) may have been more attributable to the generally-poor training given to the vast majority of soldiers of the time. Muskets were quickly phased out once rifles sufficiently improved (they co-existed for multiple decades, with rifles being reserved for light infantry who used their rifles to place accurate shots...at a fraction of the fire-rate of muskets who stayed in the hands of the line infantry, because the light infantry now had to shove the bullet in by the spiraled rifling) to do what a musket could do, but better. Muskets were categorized by what firing mechanism was used in the lock:

• The earliest versions used matchlocks, which fired by poking a slow-burning fuse into the firing chamber. These were fairly unreliable and somewhat hazardous since you had a smouldering fuse close to the flashpan when you were reloading.
• The next developed version was the wheel-lock, which used a quick rotation of a wheel against a pyrite to create sparks, making it the first self-igniting firearm. Due to it's price, it didn't replace the matchlock in most cases, only being used by cavalry, elite soldiers and gunpowder guards.
• Flintlocks replaced matchlocks (itself an evolution of earlier snaplock, snaphance, miquelet lock, and doglock mechanisms) which ignited by generating sparks when a piece of flint struck the iron frizzen, igniting the powder in the flashpan. The flint would periodically break and need replacing, but it was still safer than a matchlock. British Soldiers of the era commonly nicknamed their Brown Bess Flintlock musket "Flinchlock", because the brief flash of fire going off right in your face from the powder igniting inevitably made you flinch, especially if you weren't used to it.
  • Fusils are early flintlocks (in fact "fusil" derives the Latin "foisil" , meaning a piece of flint), and like any early technology they were more expensive then there later derivatives. Therefore Fusils were given to elite higher trained troops, hence the english/french words 'fusileer' and 'fusillade'. The primary use of Fusils while they distinct from standard infantry weapons (matchlocks) were guarding artillery since unlike matchlocks, flintlocks like the Fusil do not produce so many sparks, a major concern around barrels of gunpowder common around artillery trains!
  • Snaplock uses a flint to strike against a frizzen but is different from the later flintlocks in that the frizzen and pan are separate pieces of the weapon while later flintlocks combine frizzen and the pancover into one, which made the later flintlocks much cheaper. The user also has to manually open the pancover before shooting, which can be a problem in rain. Like the wheel-lock, snaplock didn't manage to replace the matchlock and in fact, in many regards wheel-lock was considered superior despite coming first.
  • Snaphance is similar to a snaplock but it has an additional mechanism which opens the pancover automatically when pulling the trigger, making it a lot less likely that the gunpowder would get wet.
• With the invention of the percussion cap came the Caplock, or Cap & Ball. This was the final evolution before breachloading became widespread. The cap would be fitted onto a tube to the firing chamber after the musket was loaded. Caplock firearms did not generate sparks in and of themselves; rather, they used a simple hammer to strike the cap, which would in turn ignite the powder in the firing chamber. Far more contained than flintlock, until the fully self-contained cartridge superseded it entirely. After the introduction of cartridges, it was fairly simple to convert existing caplock weapons by replacing the percussion cap tube with a firing pin, and adding a loading gate. Cap & Ball still sees use, even having a few entirely new designs created using the mechanism, due to many countries not considering them or anything prior as "firearms".

• Multi-barreled gun - In the olden days, people wanted more dakka launched at enemies, but things like magazines and self-loading weapons were still an alien idea during its time. So as an alternative people took a breach/muzzle-loaded firearm, slapped one or more barrels onto it, and reworked the trigger so they can fire more shots before needing to reload. This resulted in some particularly wacky times for guns. To this day, the only multi-barrel weapon still commonly used (disregarding military rifles with underslung grenade launchers, door breaching shotguns, or rotating barrel Gatling-style guns) is the double-barreled hunting shotgun. Some notable guns were volley guns called ribauldequin, which were a line of infantry dudes without most of the dudes. The problem was that this took very long to load, because you have one or two people ramming shit rather than 20 dudes each loading. So, that was a colossal fail in a long term artillery exchange, but quite effective for countering a charge when all you need is one volley to make mincemeat out of that cavalry coming at you.

Modern Firearms

• Handgun - Also called "pistols", handguns are small-sized firearms that can be comfortably fired in one hand (hence the name). Handguns are mainly used for close defense and as a sidearm, making them akin to daggers. Modern pistol calibers are commonly between 8mm and 11mm, although popular magnum rounds like the .50 GI and .50AE are also exist for handguns (albeit they tend to be large, heavy, and likely to fuck up your wrist from the recoil).

• Self-loading pistol - Semi-automatic pistols are magazine-fed handguns that use the fired cartridge’s energy to extract and eject the spent cartridge, recock the hammer, and feed a fresh cartridge into the chamber. A concept that took a comparatively long amount of time to get into place, with the first functional semi-automatic pistol being the German Borschardt C93, and the first mass-produced one being the iconic Broomhandle Mauser C96. These had several advantages over revolvers, like having a bigger magazine, being much easier to reload under field conditions, but the most important of which being that they were much easier to maintain. Starting with the Walther PP and the Colt M1911, most nations militaries quickly shifted towards pistols instead of revolvers, with some completely replacing them even before WW2. Revolvers stuck around longer in police service in many countries, but were pushed out of this role as well, making Revolvers only widespread on the civilian gun market, especially for hunters, where the safety and reliability of a Revolver is an advantage over semi-autos that cannot be ignored.
• Machine pistol - A machine pistol is a handgun that can fire in either bursts or in full-auto. While they're commonly thrown into that category, machine pistols are not submachine guns due to their size and use. Machine-pistols are not in widespread use with traditional military forces as SMGs and PDWs do better damage and have a longer range, but they remain popular with personnel like bodyguards or hitmen, who require a highly portable and concealable but powerful sidearm.
• Derringer - Another case of the concept being named after its inventor, "derringer" refers to tiny pistols, often used as concealed or backup sidearms, that could fit into the palm of your hand. These things have been around since the 19th century and were single-shot, though could have multiple barrels to fire off more shots before reloading, which were fired in a sequence. Due to their size and intended use (i.e: shooting someone while literally next to them); derringers typically used small rounds like .22 and below. But if you really wanted someone dead (and your wrists obliterated); some packed larger shots like .357 magnum rounds.
• Pocket Pistol - Modern versions of the derringer, those are really small handguns or revolvers that sacrifice range and ammo count in order to be as small and easily concealed as possible. Also called "subcompacts". Obviously ideal for bodyguards, spies and VIPs to use as last resorts.
• Flare Gun - While not exactly a proper firearm per se, due to being used to fire fat and slower moving flares instead of actual bullets, flare guns made from metal (any plastic ones are a risk waiting to cripple your hand) can accept tubular inserts into the breach in order to fire small to medium sized shotgun shells and pistol rounds. Granted, accuracy is going to be mediocre (assuming the inserts themselves have no rifling) and you're going to have to load and remove each bullet case like grandpa's old break action shotgun before you can shoot again. However, it works well as a hidden holdout weapon or a dual-use survival weapon while you're hunting or in the wilderness. The original ammunition, the flares themselves, can also be useful for burning combustible matter as they've been used by soldiers in the past to sabotage equipment to keep out of enemy hands or set fires off from a distance. In some extreme cases, they've been experimentally designed to fire grenades as seen with Nazi Germany's experiments with the Kampfpistole/Sturmpistole or outright used as lethal (albeit improvised) weapons during the Korean War by shooting flares that lodge into some poor Chinese soldier’s coat to burn him to death.

• Revolver - A revolving gun is any weapon that uses a revolving cylinder to load new rounds after every shot. While its commonly now relegated to pistols (a revolver typically meant a revolver pistol these days) the style is still used for some shotguns (like the Armsel Striker) and grenade launchers (like the MM1-Hawk). Historically, revolver rifles were invented in an attempt to create repeater rifles for soldiers as seen with the Colt's New Model Revolving rifle from the 1850's. However, due to lack of of a gas seal, most were notorious for leaking gas that could harm shooters or set off all the chambered rounds in a chain fire if they were pre-brass cartridge designs. By the time reciprocating chambers were made to automatically seal gaps between the barrel and the cylinders (like with the Nagant M1895 and it’s unique cartridge), revolvers had already been superseded by magazine-loaded firearms in military arsenals. However, they did make a small comeback with brass cased ammo and installed blast shields as seen with Taurus/Rossi Circuit Judge carbine or the MTs255 shotgun. Revolvers are still in use for a few reasons: they're simple and cheap to make, can easily be used by left and right-handed shooters (since spent casings aren't automatically ejected like in the case of modern firearms) and is still pretty robust compared to today's modern weapons as fewer mechanisms means fewer points of failure. Downside is that they have very limited ammunition space (because the gun was made around the cylinder you can't expand it like how you can with detachable magazines, so you either had a gun with 5-8 rounds or a bulky gun with a 12-round cylinder) and reload time (even with speedloaders, the time it takes to empty and take apart the gun to load more bullets can be lethal, which the FBI learned the hard way). Thanks to the American old west era and subsequent movies about it, revolver-styled handguns have achieved a kind of rustic yet sleek appeal to them. Revolvers come in generally the same calibers as handguns, from the modest .22 Long Rifle used for practicing and target shooting to the behemoth .500 S&W Magnum which can put down a bear. "Snubnose" revolvers refer to revolvers with shortened barrels in an attempt to make them more compact.

• Top Break/Tip up - A revolver with a hinged frame that opens to expose the cylinder. These were originally designed for cavalry, as they are very easy to load. However, the two piece frame is a weakness that limits the power of cartridge that can be used. Due to this, these types of revolvers are rarely used today, and are mostly relegated to using low-powered ammo between the .22 and .32 range.
• Swing Arm - By far the most common type of revolver, the swing arm mounts the cylinder on a moving arm known as a crane, which allows the cylinder to be exposed for loading. The chief limitation of the swing arm design is that the crane can bend over time and due to rough handling, but several tests would indicate you'd have to be deliberately trying to break your gun over a period of time for this to happen (assuming you aren't using a cheap gun made out of low-quality metal). Modern revolver-style grenade launchers are typically swing-arms.
• Gate Loading - Named for their loading gate, these revolvers can only expose one cylinder for reloading a a time, with the spent casing being pushed out through the gate by a long ejector rod. Gate loading revolvers are the earliest style for cartridge revolvers, dating back to conversions of percussion cap revolvers. Gate loading revolvers are now rare except for reproductions, revolvers designed to big cartridges, and revolver shotguns. The fixed cylinder is the strongest possible configuration of revolver and thus the most tolerant of high power ammunition.

• Submachine gun - A submachine gun (abbreviated to SMG) is a fully automatic weapon that fires pistol cartridges instead of the larger rifle cartridges. One of the first true fully automatic infantry weapons outside of the machine gun, hence the name. The weapon fulfills a similar role of the carbine, striking a balance between firepower, recoil, and bulk. They also make good stealth weapons, as most pistol rounds are subsonic with heavier bullets and thus much quieter when suppressed. SMGs are the weapon of choice for most specialist police and anti-terror forces around the world, since most scenarios they use them in (i.e. storming a building or something similar, for anything else you got snipers) don't require a lot of range and are much more compact than full-fledged rifles.

• Personal Defense Weapon - A PDW is a bit of a mix of a carbine and an SMG, firing specialized cartridges with rifle-like characteristics (usually in the 4-5mm range, shorter than a rifle cartridge but longer than a pistol cartridge) at the cost of additional weight. Its original role is as its name implies; a personal defense weapon for nonfrontline infantry, like artillery spotters, scouts, vehicle crews, commandos, etc. Back in the day PDWs weren't necessarily automatic; a pistol with a longer barrel and mounted stock could be classified as a PDW (This was done with the German C96 and Luger P07), today however these would qualify as "pistol carbines". These days PDWs are commonly lumped into the same category as SMGs, as they now fulfill similar roles.

• Shotgun - Shotguns are smoothbore weapons (as in the barrel is not rifled) designed to fire either shot (multiple steel or lead pellets) or slugs (a single, heavy projectile), although modern times have included other types of ammunition. The ability to fire multiple types of ammunition without modification is one of the main advantages to using a shotgun; converting an anti-infantry weapon into a door-breaching tool, a mini-flamethrower, or a less-lethal weapon with but a switch of the munitions. The vast majority of shotguns are pump-action or breech-loading, though as of 1905 shotguns can come in semi-automatic or fully-automatic configurations, but sheer variety of shell loads makes their reliability highly ammo dependent. For more information see the shotgun page. The most common bore size for shotguns is 12 gauge (about 18.5mm). Confusingly, higher gauges are lower in size because its based on weight of spheres of lead rather than diameter; a 20 gauge is about 15.6mm, while a 10 gauge is 19.7mm (.410 bore exists outside this and is .410 inch/10.4 mm/67 bore).

• Rifle - Rifles were originally shoulder-fired weapons that had their barrels "rifled" to increase precision, by putting spiral grooves into the barrel in order to have the bullet spin before leaving the barrel; reducing it's wind resistance (otherwise known as drag) and giving it more momentum as it leaves that muzzle. In ye olden days, these were specialist weapons given to marksmen while the common soldier carried a musket. However, because all modern non-shotgun non-explosive firearms now use rifling to improve ballistics, the term is usually reserved for a shoulder-fired long weapon, designed for accurate fire.

• Assault Rifle - Assault rifles are a term given to any rifle that can be fired on full-auto and shoot intermediate-caliber rounds, typically in the 5mm range (or a shortened 7mm round if you're from the Eastern bloc). This is usually the standard weapon of a non-specialized front-line infantryman. The STG44 is considered to be the earliest one fielded in industrial quantity, though the idea has been around since at least the first World War. Traditionally, the term "Assault Rifle" is rarely ever used by servicemen to refer to this type of weapon, and typically call them "Automatic Rifles" or "Service Rifles" instead.
• Battle Rifle - Basically the assault rifle's big brother; battle rifles are bigger automatic rifles designed to fire high-caliber rounds, typically in the 7mm range. These were the mainstay for armies in the 1950s, but the US eventually found out that giving infantry rifles with smaller rounds is better since its lighter and can allow infantry to be more accurately engage enemies better due to lower recoil (albeit at the cost of power), so battle rifles were replaced by assault rifles for front-line use and battle rifles were relegated to specialists like marksmen or support gunners (who's job permits for a slower-firing but more powerful weapon). The M1918 BAR may count as one, though the first occurred no latter than 1942's FG42. Some armies still prefer to use full battle rifles alongside assault rifles, notably the Turkish MPT-76 in 7.62 NATO was made after soldiers expressed lack of satisfaction with 5.56 MPT-55's, though no army only has battle rifles unless it's third world with nothing else around.
• Carbine - A carbine is a compact rifle, primarily designed to be used in close quarters. In most cases, carbines are based from a parent rifle, and are scaled down by using lighter/smaller parts and shortening the barrel (such as in the case of the American M16 vs M4) or is its own weapon (like the Korean K1A). These are typically given to units who need to engage the enemy at close range and need a rifle for the job, like commandos, assault teams, or other specialist units, or given to units who are not expected to fight on the front but need a compact but decent weapon to defend themselves if the need arises, like pilots or vehicle crews. Carbine may also refer to pistol-caliber semi-automatic weapons that are longer than a pistol, but this is typically only used in the civilian market. The concept of a carbine predates modern firearms, though they existed primarily for cavalry.
• Micro Assault Rifle - Even smaller than carbines; these are ultracompact rifles designed when someone needs a highly portable but powerful weapon. A MAR is basically a PDW that shoots actual rifle rounds. Much like carbines; a MAR can either be based on a parent rifle and scaled down or made as its own weapon. These tend to have low effectiveness for standard calibers, since those were designed for full length barrels, but the logistics of supply are superior.
• Sniper Rifle - A sniper rifle is a special precision rifle, specifically designed to engage targets at extreme range with lethal efficiency. Many sniper rifles use standard 7.62mm rounds, but high-performance rifles will use more potent rounds up to 12.7mm rounds for extra range and stopping power. Preferably, sniper rifles should use match-grade ammunition to provide consistency and accuracy at high extended ranges. The vast majority are bolt-action for simplicity and power (much more reliable and because all the gasses are diverted into the barrel, rather than some being diverted to work the action; the gun can launch the bullet farther and faster), but there are also a decent number of semi-automatic ones. Sniper rifles are given to special marksmen called "snipers", who are capable of engaging the enemy from extreme distances, usually well away from the scrap.
• Designated Marksman Rifle - A sort of compromise between battle rifles and sniper rifles, DMRs are precision weapons meant to be used by frontline infantry to accurately engage distant targets that regular infantry weapons cannot. Due to its role, it's generally more accurate than a rifleman's gun, but usually not as effective as an actual sniper's gun (DMRs are usually only effective within 1 kilometer, while SRs are typically effective beyond 1 kilometer). Generally speaking, DMRs avoid using the more high-performance rounds that snipers may use, as it may be detrimental for an infantryman's role.
• Recoiless - Not a conventional gun in most senses; a recoilless gun (models with rifling are called "Recoiless rifles" though people often miss this distinction) is as the title suggest, a rifled weapon without (or at least reduced) recoil. It does this by basically being a cannon with the back taken off. When loaded the cartridge sits in an open back tube, there is no breach. When fired, the explosion propels the shell out the tube, but an equal amount of gas comes out the other side canceling out the recoil. This means that total muzzle velocity is lower than a cannon with a breech on it, but they make up for it by shooting bigger shells, and with HEAT shells (thanks to the nature of the Munroe effect) the wider the diameter of the shell the more effective it is, meaning even a large slow moving projectile can do a great amount of damage to tanks. Larger, towed versions are often mistaken for field artillery or antitank cannons. Meanwhile shoulder fired versions are often mistaken for their rocket launcher cousins like the bazooka or the RPG; while both rocket launchers and infantry portable recoilless rifles lob antitank munitions at tanks, the recoilless rifle round are not self-propelled by rocket motors and rely on just momentum from the launcher to fly.
• Anti-Tank/Materiel Rifle - Essentially modern elephant guns; these rifles are geared towards destroying tanks and hard objects, although they are very much still capable of demolishing infantry (albeit overkill since rifles of this type tend to outright cause body parts to explode by the sheer amount of force they carry.). Anti-tank rifles were the norm for years (From the 1910s to the late 1970s) as they were a cheap yet effective way of getting rid of tanks, but advancements in vehicle armor has largely rendered AT rifles obsolete (at least for anti-tank roles, these things can still royally murder lightly-armored vehicles and urban housing, thus why they can be seen in use today). Anti-materiel rifles however, are a bit of an offshoot of AT rifles, and are still in use today. They are often used to take out lighter vehicles, to detonate ordnance at a safe distance or fuck up anything valuable to the other side like radars, communication devices, heavy weapons, etc... They have been successfully used against light boats and even to down the occasional helicopter. Likewise, they have been used by both professional and paramilitary forces due in thanks to their ability to annihilate cover (and hopefully what's behind it) where most conventional small arms won't. Usually chambered in heavy machine gun caliber around 12mm to 15mm barring some attempts at making man-portable 20mm caliber guns interwar to early WW2 though those didn't pan out.
• Stopping Rifle- A rifle that fires a ludicrously heavy bullet, usually as a single shot but rarely as a bolt action. As the name implies, these were developed to bring down stop big game. like elephants, that were charging at you but eventually became the precursors to anti-material rifles. Unlike the later, range or penetration aren't big concerns so much as delivering a massive amount of energy to a soft-skinned target. While hunting elephants may be illegal today, a large caliber weapon is still useful for defense against large predators like bears or lions, who would shrug off a smaller 5.56mm or 7.62mm to the body. Firing such a heavy weapon while standing or even sitting isn't a pleasant experience; without the right stance, it'll go flying once you pull the trigger.
• Everything else - Except sniper rifles and most Designated Marksman Rifles, all of the above rifles are generally "military-grade" and thus are generally not available to the public (unless you are in The Great United States Of America*, *NFA restrictions apply). Any other type of rifle will typically be called a "sporting rifle" or "hunting rifle", etc and are either bolt-action or semi-automatic. Technically speaking, most "military-grade" firearms can be modified to become semi-automatic to allow for use within the public.

• Machine Gun - Colloquially a machine gun is a large automatic weapon (though technically anything fully-automatic, ranging from a machine pistol all the way up to auto-cannons), typically fed from a magazine or a belt (or both, as is the case with the M249) and meant to either be man-portable or fired from an emplacement or mount like a tripod or turret. The main difference between MGs and the rest of the automatic weapon family is that an MG is a gun meant to fire with longer continuous bursts as a support weapon; meaning that the machine gunner applies continuous suppression fire at the enemy to keep them down (and occasionally kill those stupid enough to not get the message), while the rest of the squad maneuver. Machine guns are generally heavier, not only because of the volume of ammo they carry; but their parts (such as the barrel) are made of heavier materials so that the gun can withstand the punishing amounts of bullets it puts downrange (firing hundreds of rounds without pause can cause guns to overheat and malfunction, even catch fire or explode in the worst of scenarios, unless they're built for such a task.) Even then, barrel changes occur frequently to change warped and damaged barrels.

• Light Machine Gun - an LMG is a man-portable MG that fires the same intermediate rounds as assault rifles. They are intended to be almost as portable as a rifle (as in, they can be shouldered, but get better performance with a bipod) and allow machine gunners to provide suppressing fire at the squad level. Some LMGs are magazine-fed rifles with heavier barrels and modified bolts to allow them to withstand the heat buildup of sustained fire (such as the RPK), or else are scaled-down MMGs (such as the M249 SAW).
• Medium Machine Gun - an MMG is a man-portable MG that fires the same full-power rounds as battle rifles. These tend to push the limit of what's practical for a man-portable weapon, and when deployed are usually fired from a stationary position either on a bipod or tripod due to the recoil they generate. These weapons usually overlap with General Purpose Machine Guns and tend to be deployed at the company level or as a vehicle weapon.
• Heavy Machine Gun (classic) - The definition of an HMG has changed a bit over the last 100 years so the catagory has been split up into two categories. The classical heavy machine gun is exclusively meant to be fired from emplacements and mounts like a tripod due to their large size and weight and was designed to be fired from a fixed position: constantly, just spitting out bullets for days. Often done with the aid of a water jacket which further increased the weight of the weapon. These are the guns that created the quagmire of the great war. Their heavy weight made them impossible for an infantryman to fire on the move (regardless of what you hear; even Hollywood couldn't make these monsters man-portable in their movies, and those fire low-powered blank rounds and is being held by the like of Sylvester Stallone). But that weight also greatly limited their maneuverability and forced them to stay in a static defensive position. Usage outside of vehicle mounts died off when artillery became more precise and could easily wipe out immobile emplacements. Unlike modern heavy machine guns, classical ones used a standard sized rifle cartridge, the vickers for example used the .303 bullet same as the standard rifle of the day, what made them 'heavy' was the focus on sustained shooting to throw back waves of attacking infantry. Examples include the Maxim gun, Hotchkiss Mle 1914 and the Vickers.
• Heavy Machine Gun (Modern): a modern heavy machine gun is not designed to fire constantly, but to fire a big bullet. Only slightly too small to qualify for the definition of 'cannon' are weapons like the M2 browning .50 caliber, or 12.7 mm machine gun. Modern HMG's are powerful enough to penetrate light armor and damage fragile equipment on heavy armor (like scopes), making them formidable weapons. Examples of modern HMG's are the Russian DHSK and the American M2 Browning.
• General Purpose Machine Gun - Essentially a machine gun that can perform multiple roles of the previous stated. Examples of this are the German MG34 (arguably the first of this concept) and MG42/MG3, or (from an American prospective) the American M60 and M240, which can reliably serve both infantry-level support weapon and mounted gun roles by fitting them with the appropriate parts. The first ones used the general rifle cartridge, while modern examples are in 7.62x51 NATO or its equivalents.

• Squad Automatic Weapon - An attempt to make a GPMG that use the intermediate cartridges everyone else in the squad used. Despite the weaknesses of intermediate cartridges (limited range, low barrier penetration/destruction) being more noticeable in a machinegun role, they is still commonly used by virtue of their reduced logistical requirements and lighter weight compared to other man-portable LMG variants. The RPD, RPK and M249/SAW/MINIMI family are the main entries here, though it seems every modern assault rifle has tried to make a SAW variant with varying degrees of success.

• Infantry Automatic Rifle - A more recent concept that seeks to combine the continuous firing properties of a machine gun with an assault rifle's accuracy and ease of use. So far only attempted seriously by the US Marine Corp with the M27; while the higher-ups are pleased with it so far, there is considerable debate about whether its lower rate of fire compared to the M249 will make it less effective at providing suppressing fire.

• Rotary Machine Gun - Originally known as the "Gatling gun", man's first known attempt to have enough dakka; a rotary machine gun is an automatic weapon that uses revolving barrels that interchange every time the gun fires off a round. The kicker to this is that it allows the gun to shoot with little threat of the barrels wearing out as they interchange between shots; giving them a small window to cool off before firing again. The end result is a gun capable of firing over 3,000 rounds per minute without fail, or in a smaller scope; 50 rounds per second. Modern rotary guns are electrically powered to allow them to reach such insane speeds, and are given ammo drums that contain thousands of rounds to be able to sustain that amount of bullets being fired; so they're confined to static emplacements and vehicles (unlike what the media constantly portrays; these things are not even close to being man-portable without assistance from powered armor.) These types of guns are used almost exclusively on aircraft. anti-aircraft emplacements, or even anti missile turrets as they're the only non-missile weapon that can reliably hit fast-moving aircraft. But a rotary gun that fires 30mm rounds is powerful enough to tear tanks in two, as well (metaphorically, they only have to penetrate top armor and rate of fire helps). Unlike what the movies would tell you a rotary machine gun does not need a long spinup time to get to full speed: when the trigger is pulled the gun starts to spin and fire immediately.
• Chain gun - A chain gun is a machine gun that is fed using an electric motor. Instead of relying on the gasses from the bullet to work the action to cycle a new round; a machine automatically ejects and loads a new round in after firing a shot. Chain guns have the benefit of never jamming due to feeding failures, as even if the round is not discharged; the machine pops it out and loads a new one regardless. However, it is also not man-portable as it requires an electric motor to function, so it is only found on fixed emplacements or vehicles. Can easily fuck up any poor shmucks day by perforating the boat or car they are in. People sometimes use the words "chain gun" and "rotary machine gun" interchangeably (thanks, Doom), but chain guns are typically single-barreled, as they don't need the high rate of fire that rotary guns do outside of anti-air guns. If you see an actual rotary barrel chain gun, it's probably a CIWS like the Phalanx or the Kashtan, and while primarily designed for air defense (mostly helicopters and ground attackers who get too cocky) and to shoot down incoming shells and missiles, they can most assuredly put holes in boats and vehicles.

Actions

"Action" refers to how ammunition is loaded into the weapon.

• Single-shot: The first and oldest of all; a single-shot weapon is when users manually load rounds into the chamber. This can be anything from loading a new round, cocking the weapon every shot, or pumping the action.
  • Muzzle-loaded: The earliest form of how weapons were loaded. This meant you had to load a new round directly into the muzzle, which is where the bullets come out. In its earliest form; muzzle-loaded guns were complicated to arm; you had to fuck around with a wad, powder, and slug. In the heat of battle, you had to ram these down the barrel of your gun in the correct order, light the wick, then aim before the gun goes off. And you had to do all this while standing in the open within firing range of your enemy. Still in use because many jurisdictions have a muzzle loading only season and such obsolete arms are subject to fewer legal restrictions in general.
  • Breach-loaded; An upgrade over muzzle-loading and developed shortly after cartridges were invented; breach loaders are where the back of the barrel can be opened so that you can load a new round into it. Many muzzle loaders were converted to breech loaders in workshops near the end of the Industrial Revolution. It is still a popular setup for multi-barreled shotguns. Certain revolvers are breach-loaded as well, but given the size and design of the revolver, this gives them a notable weak point at the top of the weapon where the parts connect together. Most come in flavors such as break action (popular with simple shotguns and flare pistols), trapdoor mechanisms, rolling blocks, falling blocks (attached to levers), or bolt action.
  • Bolt-action: This type of action is where you pull the charging handle of a weapon, every time you shoot so that a new round can be chambered. They come in two varieties: faster but weaker locking straight-pull bolts and slower but stronger rotating bolt actions. Originally starting off as single shot rifles, they eventually added magazines to reduce the amount of loading required once smokeless powder was used. These were pretty popular in WW1 and continues to be used today for precision rifles and discount anti-material rifles due to their simplicity and strength.
    • Needle Rifle: An early precursor to the bolt action from the 1840's with the Dreyse and Chassepot rifles. Unlike its grandchild in WWI, these used self-contained paper cartridges where the primer is on the tail end of the projectile and the gunpowder is sandwiched between the primer and the rest of the paper cartridge. To ignite the gunpowder, the bolt's firing pin actually needs to puncture the cartridge from the back with a needle and hit the primer. While faster to fire at six to fifteen rounds per minute compared to a regular muzzleloader, their needles warped after repeating shooting and had to be replaced. And in the case of the Chassepot, their rubber seals in the breech would deteriorate and require swapping. Once metal cartridges were invented a decade later, the needle rifles were replaced with fully fledged bolt action rifles as we know them.
  • Lever-action: The cool kid of the single-action club; lever-action weapons are those where you have to use a lever to chamber a new round, which was usually mounted near the trigger. Great for shooting from horseback, not so great lying on the ground. This type was made popular by Winchester during the frontier age of the Wild West and even more by Arnold Schwarzenegger when he used a lever-action shotgun during Terminator 2. Tend to be chambered for pistol cartridges and intermediate rifle cartridges because its metalurgy and action weren't strong enough for full rifle cartridges till the 1890s, when bolt actions had started displacing it, and tube magazines requiring flat nosed rimed cartridges while market forces limit them to cartridges that are still made (a crossover that's essentially just .22lr, revolver cartridges, .30-30 and .45-70).
  • Pump-action: A pump action is where you had to pull the "pump" of the weapon to cycle a new round. This is the most common action used by shotguns. A few rifles used this setup as well (but only with round bullet heads as pointed bullets have the risk of setting off the primers), and there is one instance of a bunch of madmen creating a pump-action 3+1 (three in the tube, one in the chamber) 40mm grenade launcher.
• Automatic action/Self-loading: Unlike single-shot weapons, it uses gasses expelled by the cartridge or recoil to power a mechanism that automatically chambers a new round after each shot. Generally speaking, the semi-automatic to fully-automatic action is determined by the trigger sear, which may either inhibit the hammer from hitting against until the trigger is let go (semi-automatic), stops firing after a certain number of rounds have been fired (burst-fire), or continuously fires until ammo is expended (fully automatic).
  • Semi-automatic: A semi-automatic weapon is any weapon that can fire after every trigger pull, with the user only needing to work the action after reloading a completely empty gun. Most handguns and many rifles are semi-automatic.
  • Burst-Fire: A setting sometimes included on automatic weapons, each trigger pull fires several rounds before stopping automatically. Fully automatic fire in a handheld gun tends to very quickly go off target due to muzzle rise, but by limiting fire to a controlled burst, the gun is easier to keep trained on target. The main purpose for this setting is to defeat personal body armor; many types of armor such as ceramic inserts are only designed to reliably stop one rifle bullet, not a close grouping of several hits in succession.
  • Fully-automatic: A fully-automatic weapon is any weapon that can fire automatically, so long as the trigger is depressed, rather than pulled each time like how semi-autos work. Automatic weapons tend to be banned for civilian use outside of firing ranges and are only available to military even in countries liberal with gun rights.

Ammo Storage and Feeding

This refers to how ammunition is given to the weapon. Also the topic of a /k/ommando's greatest sources of rage; the clip vs magazine misconception. This section will give a short explanation for both.

• Pepperbox - basically the bastard child of a break-action long gun and a revolver; a pepperbox gun has 3 or more barrels loaded and ready to fire, with the gun rotating between the loaded barrels to fire in relatively quick sucession. As this was one of the only ways to get more than a single shot in less than a minute without resorting to carrying multiple guns; the design was wacky but popular during the olden ages (and still today to a limited extent for some pocket pistols). The Empire's Outriders are armed with these weapons if you want a visual of what they looked like. Most pepperboxes where smoothbore since they were made on the cheap and never intended for more than point blank fire.

• Harmonica - Also called a slide gun, it was a precursor to the detachable magazine, it was basically a reusable steel block with multiple holes drilled into the sides to house preloaded powder and shot alongside percussion caps. While loaded from the side near the hammer on adapted breechloading firearms and manually reset between shots, it still did not solve the problem of gas leakage that plagued early non-muzzleloaders until the invention of brass bullet cartridges.

• Volleygun - A variant of the olden multi-barrel family, the volleygun foregoes single, accurate shots in favor of alpha-striking to saturate the area in lead, having anywhere between 2 to 20 barrels (and you can go well beyond this if your contraption can handle it) and the size ranging anywhere from a pistol to a full-sized artillery piece. As the name describes; it fires all of it's payload in a single volley, basically making it a one-man firing line. This style of weaponry gradually fell out of disuse as more modern firearms were developed (mainly self-loading weapons, which were more reliable and accurate), but is notably still used for the "Metal Storm", a prototype weapon with truly absurd number of gun barrels that go off simultaneously to shred the ever-living fuck out of it's target. The only types still in use today are double barreled shotguns and derringers.

• Superposed load - the disadvantage to using a multi-barreled firearm is that it adds a lot of weight to the firearm. One alternative was to simply stack multiple bullets and charges into the same barrel, and then have the firearm set them off sequentially. The early version of this mechanism was prone to failures, as the bullets were not self-contained and a poor gas seal could result in multiple charges going off, destroying the gun (and the user if unlucky enough) if it was not designed to handle the stress. The King of England was once gifted several such guns and after one exploded killing the guard firing it the whole affair was deemed a very creative attempt at assassination. However, this setup was revived with the invention of caseless bullets and electronic triggers used most prominently in Metal Storm weapons. If combined with multiple barrels, a metal storm weapon can have a bewildering rate of fire. So far the technology is mostly used in multi-shot grenade launchers.

• Bullpup - A bullpup is any weapon where its action is located in the behind the trigger, instead of in front. Bullpups have the advantage of being more compact, whilst still retaining the same ballistic properties of a full-sized weapon as it can use the same barrel length, but the weapon's profile is shorter thanks to the design. However, some of the disadvantages are it not being readily ambidextrous (being that the shell ejection port is directly beside the shooter's face, you cannot switch to a left-hand grip so easily if the situation calls for it. Some bullpups can have ambidextrous controls, but implementing them typically requires tools and is not something you can swap during a fight). One of the more technical problems is weight distribution. Unlike traditional firearms where the weight is typically in the center, allowing both left and right arms to distribute the weight of the gun: most of the bullpup's weight is in the back, so most of the work is being lumped onto the dominant hand, which can cause fatigue faster. The other is poor trigger pull due to the distance from trigger to action, though there are aftermarket kits for many that can mitigate it a good deal. Modern pistols and many SMGs that feed from inside the grip are technically bullpups, since their magazine and action are behind the trigger and connected by a transfer bar, but they generally aren't counted as such. Despite their on-paper advantages, bullpups have been a hard sell on account of most of their early offerings being either hideously expensive, or finicky garbage, or inciting visceral digust just looking at it, or just straight up not-American enough to make it out of subcommittee at the Pentagon. Their lack of reach with a bayonet is a hindrance (even with modern firearms, room-to-room combat and POW control still use bayonets) while their difficulty with being modular or customizable makes each model a one-trick pony.

• Clip - A clip is a device, used for bundling bullets together for immediate use. Guns cannot use clips by themselves, they have to be loaded into a magazine first to be used by a gun. The most common version were "stripper clips": each clip held about five bullets, and to load the rifle you placed the clip on top of the magazine, then squeezed the bullets off the clip into the magazine. Another type, en bloc, was used by the M1 Garand and held eight bullets in a 2x4 configuration. The entire clip was put in the magazine, with the clip being ejected after being emptied. The last kind is the moon (or half-moon) clip, used specifically for revolvers, which holds bullets in a circular formation for loading the chamber up in one go. Clips are still used today, but exclusively to speed up loading external magazines. Filling external magazines generally requires a small disposable tool, which is included in any ammo lot packaged on stripper clips.

• Speedloader - A speedloader is essentially a clip that has moving parts, usually to aid with holding and/or loading ammunition. Two common types exist. The first is similar to a moon clip in that it holds bullets so that they can all be loaded into a revolver simultaneously, but use a locking mechanism to secure the bullets while they are being carried, then release them once they are loaded into the cylinder. While not as fast as a moon clip, it still makes loading revolvers considerably faster. Another type of speedloader is the magazine loader, which is designed to reduce the spring pressure in a magazine, making it faster and easier to load.

• Magazine - The magazine is part of the weapon that houses and feeds actual ammo into the weapon. In the olden days, many guns had magazines that were built into the weapon itself and were fed using clips of ammo that were loaded after the gun ran out. Built-in magazines, however, severely limited the potential ammunition capacity of guns as they cannot be expanded without significantly making the gun larger and was a pain in the ass to reload (such as in the case of revolvers). To counter this; people designed guns whose magazines were detachable from the gun itself. This allowed people to easily expand the ammo cap of a gun, as they only needed to ensure that the extended magazine will fit into their gun and cycle properly, they no longer needed to re-work the entire structure of the gun to enlarge a built-in magazine. It also greatly increased a person's reload speed, as instead of fumbling around with several clips to ram down the gun: they just had to detach a magazine, pull one out of their vest/bag, load it in (charge the gun if needed), and they're good to go. High-capacity magazines tend to take on weird shapes rather than the standard flat box; the most common variant is the drum magazine, but there are also double drums, caskets, and helicals. Typically the weakest part of any firearm. A large part of the misconceptions of the M16 were related to the fucktarded idea that it should be issued with DISPOSABLE MAGAZINES! They were initially not intended for repeated use, empty the mag. Drop it, crush it under your boot, reload a brand new never used mag. Worked well till some bureaucrat ordered reusing them which alongside some other bureaucrats skipping the chrome lining for the barrel and issuing really shitty ammo made with spare parts caused regular failures. Newer iterations of the magazine have since addressed these issues.

• Belts - The belt is what it is; a long belt filled with bullets, which can either take the form of a cloth belt or linked by metallic chains. Belts are the common loading method of most machine guns, who typically have ammunition capacities well beyond 100 rounds. The reason for this is that it simplifies the operation of the gun (since belts do not require them to be fed to the gun with a mechanism like in traditional magazines) and makes them less prone to malfunctions (with a gun designed to shoot continuously; you wanna make sure that there's less critical moving parts to fuck up as it's firing it's 300th round at the enemy). Belts are also much easier to transport, as the belt can be folded several times to make it more compact, versus a solid magazine. This is mostly because until H&K put out their steel high reliability 5.56 nato mag, most magazines couldn't keep up with the fire rate and were too flimsy(The Soviet counterparts that used magazines, used AK pattern magazines which you can open a beer with and then load into the gun). Pretty much every man issued a M249 with the magwell adapter, will attest to how dire you must be for bullets in the air to use it but it's better then nothing when the belt is out and your buddies can toss you a couple mags rather than sitting on your thumb waiting for someone to drop their gun.

Ammunition themselves

To call a round or cartridge "a bullet" would be the equivalent of calling of calling a magazine a clip. Bullets are the projectiles that are or to be launched, while the "round" is the entire thing. To do otherwise would summon the wrath of the /k/ommando.

Composition of the modern round/cartridge

• Casing - The metal jacket that houses the propellant, primer, and to an extent the bullet (pardoning telescopic munitions which house the bullet completely.) Usually made from brass, they can be made from steel or plastics (at the detriment of the gun itself, unless designed for such).

• Propellant - Powder that is used to propel the bullet/slug/projectile. In the good ol' days, it used black powder (which was made from charcoal, sulphur, and saltpeter - either potassium nitrate or sodium nitrate), but those clouded the air with black smoke, left soot in the gun, were corrosive, and weren't powerful. Most modern rounds use a double base powder (generally guncotton/nitrocellulose, both dry and in a dissolved form called collodion, and nitroglycerin), may include a variety of stabilizers (to improve shelf life of the round) and deterrents (to prevent the cartridge from being too "hot" and prematurely combusting or shattering the barrel from overpressure). Historically, the British formed their propellant as stiff string called Cordite stuffed into cartridges before the mainstream use of small grains took over. For artillery, they make good use of triple base propellants, which is smokey as hell but burn well with no corrosive fouling.

• Primer - What activates the powder in the rounds themselves. They're percussion caps filled with sensitive explosive compounds (like picrates, fulminates, perchlorates, styphnates, tetrazenes,or azides) that ignite upon being hit. Generally a firm dent is enough to activate the munitions. Modern commercial ammo generally use non-corrosive compression sensitive materials, though many governments kept using corrosive primers well into the Cold War.

• Bullets - What people get tripped up on in naming munitions. Being the projectile, anyone loading the munitions has a vast choice of what can be used as a bullet. Generally, lead, steel, and tungsten make the core of the round (thanks to their weight) while the outer coat for the round could be lead (since it is also very malleable), copper, and nickel, though Teflon and certain plastics can also be used. If you're feeling lucky, you can load a variety of other materials into the rounds (or shells for shotguns). Take for example salt, which doesn't kill, but you can mark people and they sting like hell. Alternatively, if you're riot police trying to suppress a crowd without killing them, you'd use bullets or shotgun shells loaded with rubber, foam, wax, plastic, bean bag rounds, or tear gas with reduced propellant. If it hits you in the head or in an unlucky spot, you might die from blunt force trauma but it's less lethal than an actual bullet.

Types of bullets

As a short note on bullets, its important to know that just because a bullet can easily penetrate armor doesn't mean its a definite upgrade over everything else. If a hard bullet like the FMJ or AP penetrates the human body and exits in the same shot; its gonna hurt like hell but unless that bullet was in the 12.7mm (.50 caliber) category or it hit something important like a lung or the head; the target has a good possibility to survive through a combination of medical aid, hormones (adrenaline in fight or flight), and willpower (with the side possibility of stimulants), and even still continue to fight onwards if they're that dead 'ard. That said, if a 12.7mm round came tearing through your body; it has enough momentum to potentially rupture a good chunk of your insides which is very lethal, but 12.7mm guns are generally not mainstay (these are guns like the Desert Eagle, M2 Browning, or M82 Barrett), so unless you're a real-life action hero, a turret gunner, or a counter-sniper; its unlikely for you to have access to these behemoths.

Likewise, if a soft bullet like the JHP or SP penetrates the body, then which expands, fragments, and/or tumbles inside; in short internal and external bleeding would be the most urgent of the target's concerns, with ruptured organs and torn muscles leaking like a broken sewage pipe, thus making HP lot more lethal and debilitating. That said, soft bullets fragment easily and body armor proportionate to it's caliber can reliably stop soft round. That said even if armored; the target is still gonna feel the impact of the bullet's force hitting against his body, and that still has the potential of killing someone if the circumstances are right (although its still unreliable).

In the end, a bullet is either specialized where it's only effective against either armored or unarmored targets, or a special combination that renders it effective against both types (although these require an experienced smith to manufacture properly).

• Ball - though if we start talking bullets we need to start with the first bullet: the lead ball, from where we derive the common term for bullets as 'rounds'. It's. . .just a lead ball though, not much to say about it. The balls were hand made, often by soldiers themselves since lead has such a low melting point, with the molds often being unique to each gun. This used largely the same process that was used for Sling bullets since antiquity. These early bullets would be smaller then the barrel and so would often 'rattle' down the barrel due to the ill fitting, which combined with a lack of riffling would mean early guns were horribly inaccurate. If one used a larger bullet that better fitted the gun, one could use rifling, but this required, (see above) hammering the bullet into place to make sure that there were no gaps.

• Minié ball- The first bullet we would know as a 'bullet', and the first truly distinct from a lead ball. A Minié ball is a conical bullet with a concave hole in the base. When fired the base flared out from the pressure of the blast, letting it engage with the rifling of the gun. This meant that it formed a seal with the barrel making it incredibly accurate, while not needing to be tightly hammered down the barrel. The best of both worlds. Combined with it's large size these things were lethal on the battle field maiming and crippling an entire generation of soldiers during the US civil war.

• Full Metal Jacket (FMJ)- Generally a lead or steel bullet encased in a soft metal such as copper. Acts a sort of lube as well as preventing fouling of the barrel. Depending on design, has a potential to fragment post impact, shredding internal organs.
  • Synthetic Jacket- FMJ ammo with a plastic jacket, which has the advantage of reducing cleaning requirements and safer when hitting steel at the cost of various things not really relevant in practice ammo. Currently only in handgun calibers and only made as practice/match ammo (though some hollow points and AP rounds do also use polymer jackets).

• Hollow point (HP)- The hollow section in the center makes the bullet expand on impact, creating a bigger hole in its victim at the expense of being less effective against armored targets. That being said, the decreased penetration also makes it safer to use in situations where over-penetration could be dangerous (e.g. on an aircraft). Certain designs have bladed tips on expansion, causing additional cutting and bleeding too. It was banned from military use by the Hague Convention of 1899, so restricted to police, civilians, and, as of 2017, the United States Armed Forces (The US didn't sign that provision, but previously stuck with FMJ even after mass production became feasible for the sake of NATO compatibility).

• Semi jacketed Hollow point (SJHP)- Same as a hollow point, but has a copper jacket to help reduce fouling.

• Jacketed Hollow Point (JHP)- Same as above, but fully covers the bullet down to the tip.

• Wad cutter (WC)- Flat tipped bullet. Not very aerodynamic but it leaves a big hole to help tell you where you hit the target. Generally for closer range paper targets as they lose velocity very quickly due to the drag on them.

• Semi Wad Cutter (SWC)- Like the wad cutter, but more aerodynamic.

• Armor Piercing (AP)- As name implies, intended to penetrate armor, be it person or equipment. However, this ultimately depends on what gun you're shooting from and what armor you're shooting at. A 9x19mm AP steel round coming from a 4" barrel will do diddly to NIJ Level IIIA, where as a 7.62x51 AP flying out of a 24" barrel will punch through it easy as you please. Modern AP rounds are often jacketed in plastic, but this is purely to protect the barrel (turns out sending something meant to destroy steel through a steel barrel results in a wrecked barrel) and adds no armor piercing quality.

• Saboted light armor penetrator (SLAP)/Saboted bullets- Think of the discarding sabots fired from a M1 Abrams or a saboted slug of a shotgun, but redesigned to be fired like a standard rifle round. The sabot is designed to the grip the rifling until it leaves the barrel, then discard after leaving the barrel. This would leave the penetrator or bullet with a high velocity while providing a sufficient spin to the bullet to keep it stabilized in the air. With a higher density and/or thinner bullet, they can potentially penetrate better than potentially even APHE. Likewise for handcrafted bullets, they provide higher velocity for a smaller bullet in a cartridge intended for a larger caliber. G

• High Explosive incendiary (HEI)- Explosive tipped munition. Generally for larger rounds (think 7.62 and beyond), they typically are meant for non-infantry targets such as light vehicles, light aircraft, and barriers, showering those inside with speeding shrapnel. Despite their implication, they might not work as well as one might think against hard target.

• Armor Piercing Incendiary (API)/Armor Piercing High Explosive (APHE), High Explosive Incendiary Armor Penetration (HEIAP)- Designed with the intentions of penetrating hard targets that HE rounds can't do alone and being anti-material in general, API and HEIAP are the answer to those targets. Generally have sufficient power in and behind the bullet (think Raufoss Mk.211), it will penetrate body armor and light vehicles with awe-inspiring ease.

• Soft point or semi jacketed - Like a FMJ, except the tip is exposed. Designed to have the reduced drag of a FMJ, while expanding upon hitting a target similar to a hollow point. Generally designed for hunters in mind.

• Ballistic tip - Similar in performance to the semi-jacketed bullet, but rather than being a solid core of lead it is designed like a hollow point, but with a plastic tip at the end to reduce drag and ensure expansion.

• Ratshot - made for smaller-caliber guns and is basically birdshot for rifled barrels. The tip is a plastic cap that contains a small amount pellets, typically within the 1.5mm range. As the name implies; the gun is primarily designed for shooting pests and small animals like rodents and grass snakes. You can use it to shoot at larger pests like coyotes or humans, but it's woefully underpowdered for the job.

• Matchgrade - ammo designed primarily for shooting competitions and/or extreme feats of marksmanship. Very expensive compared to popular alternatives and impractical for common use, but you get what you pay for: a cartridge produced with the finest minds R&D could muster, subjected to much more rigorous batch testing and quality control, and guaranteed to shoot a bullet as far and accurately as physics would allow. Rounds alone do not make an accurate firearm however, so the gun it's chambered in has to be well-maintained and designed for precise shooting in mind.

• Tracer - a regular bullet coated in pyrotechnic coating that ignites when fired. These are most commonly used with machineguns (every fifth round in a belt, to be exact) since it's useful for the gunner to accurately see where all his bullets are going, as well as make it clear to any enemies he's suppressing just who he's aiming at. Similarly rifle magazines are often loaded with tracers at certain intervals to provide indication of remaining ammo. Of course, the caveat is "tracer's work both ways" as they can give away your position; this can be mitigated by using "dim" tracers that can only be seen through night vision goggles. Sometimes also used by spotters or commanders to mark a specific target. They can potentially set fire to objects, if the incendiary compound hasn't burned out yet on impact.

• Less-lethals - Commonly known as 'rubber bullets' even though they're made of other substances such as plastic, foam, wax, and beanbag rounds for shotguns these days. Used in riot control and such, where the shooter isn't allowed to kill. The key word is "less", however. They hurt like a sonovabitch and can still kill in the wrong circumstances when they hit you in the head or a sensitive area, though. Some, such as blanks or wax, are also mixed in with real rounds before being loaded in weapons of a firing squad to make the responsibility of an execution unclear amidst the shooters. Airsoft this ain't.

• Silver - Pure fantasy, but common in there to counter supernatural creatures weak to silver. Silver bullets would suffer from many problems that rarely get mentioned in fiction. Chief among these are the cost, that silver shrinks when cast (so it's really hard to get the right size and shape), and that silver is too soft to engage rifling so even if you get the right size accuracy will be terrible. More /k/ aligned works solve these issues with solutions like sabots (which helps accuracy but still worse than real bullets), ballistic tips made of silver and frangible bullets filled with powdered silver (instead of the typical competitively cheap metal).

Types of Rounds

Apart from the traditional type of rounds, here are some unique ones for reference.

• Blanks - What you commonly see loaded in movies. Blanks are basically that; the round has a primer and powder, but the bullet is just a paper or plastic sheet (or "wad") designed to keep the powder in, so you get the sound of a gun going off, but not the damage. That said, blanks can still kill people, that wad is still powerful enough to liquefy organs and break bones if you were dumb/desperate enough shoot someone with a blank at close range (plus the gas itself is hot enough to cause severe burns at that range). Movie armorers make a point of demonstrating this with things like fruit before letting anyone touch blank firing guns. This is why instead of blank-firing guns, actors will use flash paper guns at close range for safety. There's also blank ammo specifically designed to make as much noise as possible for the purpose of disorienting and intimidating people in an area. In a military sense blanks do have a use: typically for turning your rifle into a grenade launcher, using the expanding gases to launch a grenade held at the muzzle by a cup. Blanks can't cycle a gun's firing mechanisms in the same way as standard bullets can, so self-loading guns that fire blanks have to either be made specifically to fire them or be equipped with an adapter that compensates for the reduced pressure.

• Caseless - An old but futuristic concept, a caseless round has everything required for the bullet to be launched, inside the bullet itself. That's 65% more bullet, per bullet.This removes the need for guns to eject spent shell casings after every shot, reducing weight and ammo costs. While this has been pioneered since WW2 and a few prototype examples for it were already developed (like the G11); caseless rounds are still determined to be too unreliable for field combat use in comparison to traditional ammunition, so as of today their use is largely limited (mainly to grenade rounds like the Russian VOG-25 grenade). Their biggest disadvantage is that ammo cases normally transports a large amount of heat out of the weapon, and, if you have paid attention in your physics class, you know that heat always has to go somewhere, so with caseless ammo, it naturally goes into the weapon, making it prone to overheating and dangerous cookoffs, unless the ammo somehow counteracts this, making it more complex and therefore expensive in the process, and if you've at one point in time interacted with any branch of a national government, you know that the word "expensive" usually spells doom for any project that it is attached to.

• Gyrojet - A unique but largely impractical cartridge in the gun circuit, WH40K's famous boltguns run on the same concept as the gyrojet. Basically, the bullets are miniature rockets that build up speed as they travel, capable of exceeding the speed of sound after traveling 60ft. While the idea sounds cool; gyrojets were required to gain minimum distance to achieve their full effect (if you fired at point-blank for example, they didn't really do much), had a design flaw in their propulsion system that made the rockets prone to corkscrewing off-course, and were highly temperamental to environmental conditions, not to mention the costs. At the end the concept was a bust as it didn't really do a lot that couldn't be achieved with traditional small arms for cheaper. Still GeeDubs thought it was nice and became the basis of how boltguns work, where it's largely the same but with more techno-flubdubbery and "because future".

• Magnum - Unlike what vidya gaems portray, magnums aren't really super-mega handguns of death. A magnum round is basically a parent cartridge that's been enlarged so it does more damage due to a combination of larger mass and more powder used (so it flies faster and hits harder), and this can be anything from the .357 magnum handgun round used by revolvers, to the large caliber .338 Lapua and Winchester magnum rounds used for precision sniper rifles.
  • Special - An earlier equivalent. The only two to see continued existence are .38 special and .44 special which also went from black powder to smokeless powder, both of which coincidentally have even longer magnum variants; however both are lengthened only as a safety precaution to make them different, as smokeless powder left plenty of room for more powder.

• Overpressured - Designated as "+P", overpressured rounds still uses the same cartridge (unlike the magnum), but is loaded with higher-pressure powder that releases more energy when fired. It sounds like a nice way to up your damage, but guns have a level of pressure they can tolerate, and if your gun isn't designed to do such and you use +P rounds; you run the very high risk of destroying your gun (and the rest of your body if you're that unlucky). There are guns that are proofed to fire +P and +P+ ammo but it is typically used in SMGs. Certain batches of surplus ammo will blow up guns because they were made to be used in more robust SMGs and not commercial pistols, poorly stored, or just plain poorly made.

• Subsonic - Rounds designed to shoot slower than the speed of sound to prevent creating the loud cracking sound a projectile makes when it goes beyond 345m/s, making them more stealthy. There's three ways to go about this. The first is to put less powder in the round, or use specialized one that explodes with and imparts less energy (although this may cause problems for self-loading guns, who are not designed to cycle using less powerful ammo). The other is to make the bullet much heavier than usual so the standard powder load doesn't have enough energy to have the bullet break the sound barrier, although this translates to slower projectile speed and lower range, but increased chances of armor penetration as heavier bullets retain energy much more efficiently than lighter ones. The last is a combination of the two methods. Subsonic munitions are primarily used in silenced weapons for their sound-reduction benefits (the most extreme case of which is that only the cycling of the gun can be heard, the gunshot is virtually inaudible), although some take advantage of certain subsonic rounds' heavy bullets and low-energy for defeating armored opponents at close range (as the lower energy translates to lower chances of overpenetration, which AP bullets have a tendency of doing when tearing through non-armored parts of the body).

Types of shotgun loads

• Buckshot - The shell is filled with lead or steel pellets, each of which is typically around 15mm each (it ultimately depends on the bore), that spread out once discharged. Poor at penetrating armor and limited effective range comparison to other firearms as the pellets scatter and the pellets are too small to do serious damage individually (Although do note that unlike what the vidya gaems portray; a decent 12G shotgun loaded with buckshot is effective upto 30-50m, not just in point-blank range); but they do cover a fairly large radius and the force of 8-12 pellets impacting against your body will send you tumbling and rolling on the floor in agony, even if they don't penetrate.

• Birdshot - Similar to buckshot and more pellets, but the pellets are smaller (5mm and less, although still depends on the bore). As their name describes; the ammo is designed to pelt down birds by throwing as many bullets at the target and hoping atleast a few of them hit. You can use them against non-avian targets aswell and they'll do something, but they don't pack the punch you'd like and don't expect them to dent body armor too much. Their ineffectiveness against human targets was demonstrated by a (possibly drunk) Vice President of the United States when he shot an old guy in the face with some and the only lasting damage was the voice.

• Slug - Instead of multiple pellets; the gun fires a single, heavy lead projectile, similar to how traditional ammo works. Because shotgun barrels are not rifled; slugs do not have the range nor accuracy rifles do, but because of their weight and the shotgun's fairly large caliber; they're fully capable of crushing their way through armor at close range. Slugs are typically used for hunting large game in areas where rifle ammunition isn't allowed due to the risk of overpenetration.

• Breaching - A specialized variant of the slug round, breaching rounds are designed specifically to destroy door locks at extremely close range. Generally composed of very dense powdered steel held together with wax.

• Less-lethals - Designed for riot control where the shooter isn't allowed to kill; the bullet is either made of rubber, paint, or beanbags designed for minimal penetration, while the powder used in the rounds is less to reduce the projectile's velocity. The end result is a bullet designed to simply cause shock and pain to the target in order to incapacitate them long enough to be arrested and not rejoin the fight in the meantime. That said, you're still talking about launching an object at someone at speeds similar to cars speeding on a highway; so hitting vulnerable parts of the body like the head, neck, or ribs can still result in a fatality. On the flip side, anyone wearing bullet-resistant armor won't be affected too much.

• Chain-shot - Typically reserved for olden cannons, the chain-shot is two cannonballs linked with a chain. The spinning contraption was intended to tear through a ship's mast and sails. Obsolete as fuck, but it is still possible to replicate this with shotgun ammo. Basically you tie two pellets or slugs together so that when they're discharged; they're basically flying garrotes. Awesome, but because of how unpredictable bullets are while in flight, it's highly impractical for combat use.

• Flechette - Buckshot, but instead of pellets; the shell is loaded with small metal darts. They achieved better penetration and range than traditional buckshot; but because shotguns aren't really designed as precision weapons; they were highly impractical for combat applications. They destroyed barrels and tended to deflect off really silly things like raindrops.

• Explosive Rounds - The shell contains an slug that explodes upon impact, capable of using anti-armor or anti-personnel shells, basically turning the shotgun into a portable grenade launcher. Not as powerful as the real thing, but invaluable when you need accurate explosions but not the excessive collateral damage or restrictive weight and mass. Has seen some use in rifle rounds on the eastern front of World War II as well as in .50 BMG (officially for use on objects, not people).

• Dragon's Breath - An odd type of ammo. DB shells are loaded with magnesium pellets. When discharged; they create a short but hot burst of fire that burn at temperatures upto 1,600°C. While not really used much for conventional combat due to its status as an incendiary weapon, blasting a person with this at close range will create about the same results as a giant fire-breathing lizard incinerating an unlucky knight to death, hence their name. Also destroys barrels, as dragon's breath burns hotter than the melting point of steel, and close to the melting point of chromium (two of the most common metals used in gun parts).

• Misc - Shotguns aren't really picky with ammo since they are manually operated and don't depend on a gas seal as much; just about anything can be used for bullets if worse comes to worse/you're bored. Could be lego pieces, could be old hard candy, solid scrap,frozen meat or even glass. They can also fire flares (but need stronger propellant and an unchoked barrel to avoid getting stuck and melting the barrel). Hell, it can be a Sly Marbo tabletop figure if you could fit him inside a shell and prevent him from disintegrating from the force while exiting the barrel, the choice is yours. (More likely blow up your gun as Sly refuses to die and gives you the finger for trying.) Incidentally this unfastidious in ammunition also means that in a fantasy setting you can basically load anything you want down the barrel of a shotgun to deal with basically any monster that had a weakness. Wooden stakes for vampires, Cold iron for fae, silver for werewolves, the aforementioned dragon breath for flame vulnerable monsters, salt if that's a thing demons hate in your mythos, freeze holy water into ice and you could still likely shoot it with a sabot. Basically shotguns should be the go to for the modern murder hobo.

Manufacturing of Firearms

Brief Overview

The production of firearms historically speaking has been an, err, interesting path. The first firearms were little more than metal (or whatever other material one so chose) cylinder with with one hole for the ignition of the powder and one for the projectile to be projected. As time passes on manufacturing techniques got more advanced, leading to triggers which frees up one hand from having to push a hot object into the powder. Most used a sort of striker to ignite the powder, be it flint or rope. Around the early to mid 19th century, self-containing cartridges became a possible reality. As such the firearm had to change too, with an action either simply accepting a round into the barrel or an action that would be worked to put it in. Near the end of the 19th century and start of the 20th, auto-loading firearms became possible, but the actions had to become more complex to automatically feed the round by means of either recoil or gas. After that, guns haven't exactly changed too drastically (still major changes) in the current 21st century, pardoning the much higher efficiency of the modern weaponry. The complexity of modern firearms however doesn't interfere with how cheaply they can be produced. As such, there are endless aftermarket gun parts for sale around in places such as the USA.

DIY

File:.45 ACP ISB SMG.png

.45 ACP ISB SMG designed from a STEN/Sterling, but has many parts that differ. According to the designer "I like to think of it as a cross between an FG-42, a Welrod and a Sten."

First and foremost: guns are not toys, and should never be treated as such.

It comes as no secret that one can manufacture their own guns in one's own home so they chose to (Just ask the Afghans). Depending on the skill of the user, the manufacturing tools used, material quality of the parts being used and/or made, design of the gun, and so on, a DIY can range from a explode-in-your-hand zip gun all the way up to high-quality rifles that have a minute of angle (MOA) of 1 or less. All one need is one's imagination and a firm understanding on how a gun works from the inside out and machining. In addition to that, the internet has a broad data base on the knowledge and schematics of guns. Additionally, while online information is enough to give you a rough understanding to create black or smokeless powder to add to hand-loaded cartridges, the proper equipment, environmentally controlled rooms, and ingredient ratios are hard to get right the first time without causing an accident (as attested to the many Chinese and European chemists who historically died while tinkering to get the formulas right). And while you could arguably use firework material or even discarded nitrocellulose film tape instead, most people are going to simply buy their primers, propellants, and projectiles off the shelves to reload their spent casings instead of building a lab in their basement.

Careful you might blow your eye out

That said, DIY-guns require a decent understanding of physics, chemistry, and mechanical engineering to manufacturer at all, so unless you're a Mekboy with all the know-wotz implanted in your brain; its highly recommended you read up first, lest your firearm's first unwitting victim is you.

If a modern rifle was a stormbolter.

Examples of DIY are:

• Zip gun: Bottom of the barrel trash guns that are considered too simplistic and bare bones for anyone who isn't a post-apocalyptic raider or somewhat ambitious convict. These guns are rather unique as they require next to no skill to actually make, often incorporating rubber bands, nails, plumbing supplies and zip ties into their construction (hence their name) to craft something that counts as a gun while firing (sometimes); a common example is the slam-fire shotgun which is literally two pipes (one just wide enough to comfortably fit the shell with the other one wide enough to fit the other pipe while sealed at one end) that are slammed into each over where a fixed nail at the end acts as the firing pin.

• Standardized design: With gun laws around the world becoming ever more strict its little wonder that some would protest such bullshit by creating guides on how to make fully functional semi professional designs in your shed. At one end of the spectrum is the infamous Luty gun which is a family of submachine guns specifically designed by a man named Philip Luty to be buildable by anyone with some basic hand tools in protest to the British government’s delusion that they can prevent criminals from getting guns by making guns illegal. Said designs (including the related Carlo SMG’s) have been found in the hands of organized crime and guerilla groups in particular lawless or insurgent-prone regions like South America, Palestine, and other developing countries. At the other hand of the spectrum is artisanal gunsmiths like the ones in the Khyber Pass region on the Afghan-Pakistani frontier that clone their gun parts off existing models they got their hands on and disassembled as a master template.

• Experimental design: Every line of guns started out as a experiment somewhere. Some catch on, some don't, some just are there because why the heck not? Want to have dual barrels on your gun? Go for it! Add a counterweight to the gas block so that the recoil is next to nothing? Makes shoot a breeze! Add a round cam to your bolt so you can have a smooth action and reduce wear on the gun? No reason not to! The choices are endless if with time, diligence, and a bit of imagination.

• CNC Manufacturing: Avoiding the painstaking effort of machining it by hand a machine do it for you? A Computer numerical control (CNC) machine can easily set the settings in any digitally-connected presses, lathes, mills, saws, and drills to crank out receivers and whatever other parts you need assuming you have the plans on the computer and the materials to be worked. In most countries, it's only necessary to mill some of the components as most firearms have a single designated part which is legally viewed as "the gun" (usually the receiver for rifles and the frame for pistols) and everything else is considered replaceable. The downsides of that CNC are a bit pricey relative to their hand milling machine counterpart. However some go for as low as $1200, which is roughly the same price as a mid-tier intermediate rifle in the USA.

• 3D Printing: while of questionable quality and legality the same way 3D printed miniatures are with “official” tabletop gaming tournaments, the additive manufacturing spinoff of Casting can theoretically enable you to form all but the most stressed parts of a firearm. Barring the barrel, receiver, and firing chamber (besides springs, screws, and attachment pins) of a firearm that are better off milled or stamped from metal, one can theoretically 3D print all the other parts of a gun frame from the stock and grip to the fire control group and trigger. Examples range from small pistols (like the single-shot Liberator) to full power rifles (such as the Amigo Grande clone of the CETME) with all other kinds of intermediary weapons in between. For simplification (unless incorporating an existing gas piston system attached to a pre-made metal barrel or using a much weaker roller/lever delayed blowback system), most aren't more advanced than blow-back powered semiautomatics as building a gas-operated piston system with plastic is suicide. In addition, unless built by someone who really knows what they’re doing, actually shooting full-power ammunition out of a 3D printed gun is as risky or worse as firing bullets and shotgun shells out of a plastic flare gun. So far, some 3D printed guns, like the FGC-9 carbine, have been seen in the hands of organized gangs, neo-IRA, or Burmese partisan groups.

Relations here

Most fantasy writers tend to exclude firearms. There are a variety of reasons for this, such as:

• Most fantasy comes from Tolkien, who, being a naturalist who largely despised industrialization, did not put guns in Middle-earth, although gunpowder does exist, used by the wizards (Gandalf's Fireworks and Saruman's Fires of Orthanc) and by the orcs.
• Most fantasy (whether copy-catting Tolkien or not) is based on medieval Europe. Depending on your definition of "medieval," Europe did technically have firearms towards the very end (crude and unreliable ones, but firearms nonetheless), but most authors base their fantasy on earlier medieval Europe.
• As in real life, firearms mean that vulgar, dirty, peasant conscripts can take down the author's Mary Sue noblemen knights that trained so hard in the arts of swordsmanship and melee combat, though if the writer had any historical knowledge they would know that armor can be made "proof" against early firearm bullets (which is partly what spurred the development of full-body plate mail to begin with, as a sidenote) or that a crossbow or longbow can just as easily (in fact, MORE easily due to the general shitty performance of old guns) turn an armored man into swiss cheese.

All that being said, most fantasy authors are much more open to cannons, which became viable on the battlefield long before smaller firearms anyway, especially in naval use (cannons were a huge game changer for sea battles). Some even make room for crude rocket launchers, especially if there is a not-China/not-Korea in their setting. (Laugh, but a big firework rocket will put a sod on fire and ruin his day just fine, doubly so if the morons are in wooden fort.)

Generally speaking, if a world has both the "stock" fantasy races and guns, there will a strict hierarchy of who uses them, from most to least likely:

• Dwarves: They almost always have the best, most plentiful guns. If only one race gets firearms, it's likely going to be them.
• Gnomes: As tinkerers, they're frequently on a different tech level from everyone else, including firearms.
• Humans: Unlike the other races, which are usually an all-or-nothing deal, different human nations have different likelihoods of having guns. Italian and East Asian analogues, as well as the "industrious" or "scientific" nations, are much more likely to have them. Your barbarians, guys keen on knights and chivalry, and the more conservative less so. If the nation is Post Renaissance, expect pike and shot style IRL analogue armies. If your setting has pirates, you pretty much have to have cannons at the very least.
• Orcs: Orcs would probably love guns if they could actually build some. However, they're usually either incapable of building things or have a hard time organizing themselves to the point that large-scale firearm and powder production is possible. Even so, they could still obtain them them by other means such as fighting as mercenaries for guns and stealing them off the corpses of the fallen and similar. They are higher on the list if they are more like Tolkienian orcs, which can be fairly well organized and "delight in explosions" enough to manufacture their own gunpowder, if only for simple bombs. If Orcs are of the more Chaotic Evil variety then they will barely have crossbows, let alone guns. If Orcs are of the Klingon variety, as in the violent tendencies are normal enough that the civilization can function, then they will LOVE big guns.
• Elves: Being arrogant pricks, they see guns as crude, inaccurate, foul-smelling contraptions that are no substitute for a bow. However, they'll still use them when necessary, even if they don't like it. That said, elves also had a good reason to not use them, namely most firearms in a fantasy settling are arquebus-type single-shot smoothbore weapons, which are outranged by longbows. Longbows are even decent against most kinds of armor (ask the French). The main advantage of firearms, even early ones, is ease of use and armor penetration though armor could be made that could stop an early handgun. The main problem with longbows is that it takes years to learn, which is not a problem for long-lived elves. Between a smoothbore handgun and a longbow, the bow is simply a better choice to an elf. The problem of course is that longbows are about as good as bow technology can get while handguns can be improved to rifles, against which bows only have rate of fire as an advantage, then Repeating Rifles, which bows have no advantage at all against. So while Elves may have an advantage to sticking with their longbows well into the age of pike and shot, if they're not careful their Longbows will end up fighting against Springfields and Winchesters and they will end up the worse in that exchange. If tech reaches that point, expect the Archer/Hunter stereotype to turn into Snipers/Mad minute riflemen. And if they're still vehemently opposed to foul-smelling gunpowder, it's possible they could consider air guns (like the Girardoni air rifle used in Europe and by Lewis & Clark's exploratory mission). Assuming they can make a reliable air pump and pressure tank on their own.
• Wood Elves and other Fey/Nature types: They'd rather die than use a firearm, even if the rest of the world has moved onto biplanes, bolt-action rifles, shell-firing cannons, and tanks. If this happens, this means they either have powerful magic (so the actual weapons used are unimportant), they are really really good shots with a bow, they have much stronger friends (Think like the amish) or they're about to get colonized. That said: the problem they have are not guns themselves, but making them as mass production always has some environmental costs they can not stand for. If they could get their hands on some way to make guns that did not harm the environment in the process, at least anymore than making a sword does, they might go small for small scale fire arm production, but this is rarely explored in fiction.

For how this conservative attitude tends to apply to tech in general for fantasy settings, see Medieval Stasis.

Of course, sci-fi writers almost exclusively use firearms, seeing as how it's THE FUUUUUUTTTTTUUUUURRRREEEE. The exceptions are Warhammer 40,000 and Dune: although guns are the main combat implement in 40K, close combat is still alive and well, and most armies have at least one elite, close-combat unit wielding weapons that are distinctly not firearms; in Dune, guns are pretty much dead as a weapon of war, as personal-scale force fields stop fast-moving matter (like bullets) from crossing them, but slower matter (like swung knives) can pass through, and if a lasgun blast touches the field, at least one end of the equation comes out "BOOM!!!". Most sci-fi universes do have close combat weapons on the scale we see in modern warfare, though, like in Mass Effect, where, as the Reaper forces (who are basically Necrons and Tyranids combined) invade the galaxy, people begin developing their Omnitools to snap-produce a white-hot blade of hard metal above the wearer's hand... And then there's the Krogan, who are too bloodthirsty and too large to properly take cover, so they headbutt things instead of using guns.

Rules

Most fantasy RPGs deal with firearms the way they deal with lots of things that threaten their Medieval Stasis: terror, suspicion, and shitty rules. If you have the option of using a firearm in most games, it probably has one shot that's weaker than a bow, then takes an entire encounter to reload, and is illegal everywhere in-setting in case you didn't get the hint.

BECMI Dungeons & Dragons doesn't have rules for firearms, but there were one or two adventure modules that incorporated a crash-landed spaceship, with weapons the players could loot. They were treated as magic wands and staves. A few issues of Dragon magazine offered rules for early cannons and hand cannons.

Advanced Dungeons & Dragons mentions guns in a tucked-away subsection on importing TSR's Cowboys & Indians game Boot Hill to AD&D (DMG, pg113). Revolver pistols and Gatling guns would do as much damage as a longsword; shotguns as much damage as a two-handed claymore, a (thrown) stick of dynamite does 4x the damage of a short sword. The rules insist "...when gunpowder is brought into the fantasy world it becomes inert junk, ergo, no clever alchemist can duplicate it." To reinforce this concept, the Manual of the Planes included rules for factors of prime material planes, one of which determined if complex (read: setting destroying) chemical compositions like blackpowder would even work in said plane. If you have any knowledge of chemistry, you may cry now. Notably, Greyhawk had a god of firearms, and his paladins were basically Wild West sheriffs.

Advanced Dungeons & Dragons Second Edition included the arquebus in the Players Handbook, where they were depicted as slow, powerful and expensive (500 Gp!). They were also potentially dangerous to the user as the result of a bad roll. It was painfully stressed that the inclusion of firearms in the campaign was the call of the DM. Firearms were a bit more common in the Spelljammer setting. Moving away from the classic fantasy background, there was the historical campaign sourcebook A Mighty Fortress that introduced rules for firearms of the 16th and 17th centuries and the Masque of the Red Death setting for Ravenloft pushed everything into a gothic horror version of the 1890's.

D&D third edition has a section on advanced technology (DMG, pp162-164) for Renaissance-era, 20th century, and futuristic weapons. The weapons are more powerful than what can be found among ranged weapons in the Player's Handbook, but also heavier and more expensive and require exotic weapon profiency (despite muzzle loaders taking off because they were much easier to teach than archery). You're better off with magic crossbows. The White Wolf Ravenloft material also includes them with minor tweaks.

Pathfinder greatly over complicates guns: they have shorter range than bows without magical items, take longer to reload, and have at least a 1/20 chance to break or explode every time you fire it, and use up more expensive ammunition. As though this wasn't enough, they have a stiff feat tax needed to make use of them and the fact that there's really only one major gun factory in the land, the Gunworks of the small nation of Alkenstar, and they keep most of their guns to themselves. In return they hit harder, have a terrifying 4x crit modifier, and use touch AC in the first range increment, effectively ignoring armor when fired close up. A specialized class, the gunslinger, is centered around the use of firearms. Energy weapon specialists in Iron Gods have it a bit better, though ammo is limited for most of the adventure.

Dragonmech has guns, sort of kinda, as well. Only instead of using gunpowder, they use steam to propel the bullet like an airsoft gun. they can only be fired once every other round as the pressure needs to build up. There Treated a bit like crossbows that do more damage and can shoot a little further.

Dungeons & Dragons 5th Edition includes a section on firearms in the Dungeon Master's Guide. They hark back to 2nd edition in terms of stats, fitting the general tone of the game, but aren't quite as punishing for a player to learn to use and make. And with the increased emphasis on houseruling and homebrewing, modding the Crossbow Expert feat to work for them seems a simple leap of logic. The "race builder" guide in the back even suggests changing around the dwarf weapon proficiencies to include them! Furthermore, if you want to get your Expedition to the Barrier Peaks on, it includes some futuristic guns as well, like lasers and disintegrators.

Warhammer Fantasy features firearms based on early real-world equivalents, like flintlock pistols, musket rifles and the blunderbuss. Although deadly and still on the experimental side, they're also considered very unreliable and are prone to misfire and sometimes even to explode. Rpg-wise, firearms were already included in the core rulebook of Warhammer Fantasy Roleplay 2nd Edition, but were later somewhat expanded in the Old World Armoury supplement. Some variations that function like firearms were also added as weapons to some Skaven classes in the Old World Bestiary supplement. Generally speaking, firearms require more costs in order to be used, as each shot requires a firearm shot (bullet) and additional gunpowder. Except for the obvious disadvantages of becoming useless once getting wet and longer reloading times, firearms deal more damage than bows and crossbows, with more complex models even having a repeater function, but obviously longer reloading times for each barrel to be loaded again.

Iron Kingdoms takes full advantage of guns in its steampunk setting. Most of the kingdoms have at least Napoleonic-era muzzle loading rifles. Cygnar is a bit more advanced with revolvers and machine guns, as well as tesla-style lightning guns. The iconic Gun-Mages carve runes onto their bullets to allow them to empower their shooting with spell effects.

Medieval Weaponry
Melee Weapons:	Battleaxe - Dagger - Lance - Mace - Club Pole-arm - Spear - Sword - Warhammer
Ranged Weapons:	Blowgun - Bows and Arrows - Cannon Crossbow - Firearm - Rocket - Shuriken - Sling - Incendiary Weapons - Artillery
Armor:	Armor - Fantasy Armor - Helmet - Pauldron - Shield