Lasgun: Difference between revisions
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==== Tau Pulse Weapons ==== | ==== Tau Pulse Weapons ==== | ||
Ah, the cheesiest, shootiest army ever. Their weapons are bound to be really good, right? Well, pulse weapons suffer from reduced range or horribly long barrels. Magazine capacity is good, but not nearly as good as the lasgun. They have really great stopping power, but the armor penetration is no better in a galaxy when no one goes into battle unarmored. Recoil is also a thing, while not horrible as the one of a boltgun. | Ah, the cheesiest, shootiest army ever. Their weapons are bound to be really good, right? Well, pulse weapons suffer from reduced range or horribly long barrels. Magazine capacity is good, but not nearly as good as the lasgun. They have really great stopping power, <S> but the armor penetration is no better in a galaxy when no one goes into battle unarmored </S> better according to both fluff and pre-8th crunch (comparable to a non-primaris bolter) but doesn't fare much better against anything tougher than Flak armor. Recoil is also a thing, while not horrible as the one of a boltgun. | ||
== Las weapons and AA == | == Las weapons and AA == | ||
Revision as of 23:15, 3 April 2019
"IT'S NOT A LASER! IT'S A LITTLE LIGHT BULB THAT BLINKS!"
- – Woody, Toy Story
"What do you call a Lasgun with a taclight mounted under the barrel? Twin-linked."
- – Any 40k player evar (Hilariously, GW has caught onto this. Less hilariously, on Regimental Standard they've got an in-universe nod where any Guardsman who makes this joke is sentenced to flogging)
The humble (and we mean humble) Lasgun is the standard-issue armament of the average Imperial Guardsman in the Warhammer 40,000 setting. Given the incalculable number of Guardsmen under arms and the sheer scale of the Imperium itself, it is safe to say that the lasgun is probably the most common weapon in the entire galaxy that isn't some underhive piece of junk like stub guns, knives or other miscellaneous weapon. On the tabletop it shares the same rules with autoguns.
The name is rather obviously a portmanteau of "laser" and "gun", but argument rages over how the word is meant to be pronounced. Many claim that the "las" should be pronounced "layz" (or in other words say that it's pronounced with a long "a", as the first part of "laser"), but others contend that this sounds retarded, and "lazz-gun" (or a short "a" sound, as in "glass") is a better pronunciation. According to Games Workshop, its name is pronounced "Laze-gun"; however, Jeremy Vetock and Duncan Rhodes both say "Lazzguns," so it really is a toss up. (And unimportant).
It is almost universally described in the fluff as discharging with a sharp crack (caused by the beam ionizing the air it travels through), but some authors describe the lasround as either a "bolt" as in Star Wars or as a "beam" as in Dawn of War. Other features of the weapon have greater variation - some Black Library works and items such as the Imperial Infantryman's Uplifting Primer describe the weapon as possessing a fully automatic firing setting; this feature is represented by Rapid Fire rule on the tabletop, but not represented in Dark Heresy, which can be explained away by virtue of the fact that there are many different patterns of Lasgun produced throughout the Imperium.
There is also some dispute as to the color of the "beam". Some fluff claims it to be blue, while games like Dawn of War portray it as red or something of a reddish-yellow. The popular Gaunt's Ghosts series of novels by Dan Abnett say that the Imperial weapons fire blue "beams", while the Chaos weapons fire red ones. In order to fix this mess, we have proposed a Scientific fact on the issue...
- The Fact: the energy of each individual photon is determined by its frequency (i.e. colour); power output is energy per second, meaning the same power output is achievable with either more photons per second at a lower frequency (bright red) or fewer photons per second at a higher frequency (dim blue). In either case, the colour is also dependent on the gas it is traveling through, as the amount of energy transferred to the surrounding medium via [[1]] depends on the mass of each gas particle, while the brightness depends on the amount of gas particles, so the laser would look different on different planets. Regardless, a fired lasround would never look like a glowing projectile "bolt" to any camera (such as a human eye) operating at a frame rate lower than approximately a billion frames per second, so those depictions can safely be assumed to be heresy. It would look like an actual pulsed laser, i.e. a "beam" that visibly spans the distance from the weapon's muzzle to the impact point, for the duration of the pulse. The popular visual idea from other popular sci-fi weapons that fire glowing projectile bolts are not lasers at all, instead being described as magnetically-contained plasma bolts.
Why the Lasgun sucks
See Also: Lasgun Patterns
The lasgun is rather pathetic compared to the mainline arms and armour of most of the other armies of the setting, useful only by virtue of the fact that Guardsmen come in ridiculous numbers (except in comparison to Tyranids, Chaos Cultists/Zombies, or Orks) and the application of statistical probability. The weapons are often derisively referred to as "flashlights," based on their individual uselessness, although this is arguably more of an example of how ridiculously tough everything else is in the setting.
The 6th Edition rulebook describes the lasgun as severing limbs at close range but further away it only goes about as deep as the liver, explosively flash-boiling said liver and all other squishy bits in the laser's path. That sounds awesome, until you remember that nearly every enemy of the Imperium has heat and energy-dissipating armor, redundant biology, or simply outrange them. Pretty much the only enemy an individual lasgun can reliably kill are other humans. They are on the same level of effectiveness as autoguns (which are basically AK-47s IN SPACE), except lasguns are even more durable, reliable, accurate (due to low to no recoil and the fact that the beam is not affected by gravity or wind, though shooting through a dust cloud or fog on the other hand is more problematic, so a B over all for atmospheric effects) and less dependent on massive ammo supplies; a single power-pack can, depending on the gun's setting, afford up to 100 to 140 shots on average, while an autogun magazine is usually 20-60 bullets (which, fun fact, is generally what typical lasguns set to max power usually can fire.) Plus you can recharge their batteries from Chimera generators, sunlight or even fire, while an autogun is useless once out of ammo for anything other than a fancy club or if you have the good fortune to have a bayonet, a vaguely sharp stick. Not that said bayonet on either weapon will help against orks or 'nids. And given the general competence of Munitorum depots, you'd probably end up with ration packs instead of ammunition, though this of course applies to lasgun power-packs, as well.
Combine this with most lasguns seeming to come pre-set to "medium power" (granting between 40 and 80 shots a pack with usually enough penetration power to reliably punch right through Imperial Guard's flak armour (or xenos-made equivalents of such) and many places not bothering to actually include how to adjust power as part of basic training - probably (rightly) assuming the soldier won't live long enough for it to matter - and you end up with an energy-based assault rifle, that is actually good for taking down lightly-armoured infantry with resilience to ballistic damage roughly equal that of a normal human (as it is in case with eldars or tau), but that's exactly what it was designed for - nothing less, but also nothing more. Unluckly for typical guardsmen, however, there are warrior-creatures of the 41st millennium that are either equipped with armour, capable of deflecting even heavy stubber or bolter shells impacts, or biology so robust, that it is able to take a hit from heavy stubber's bullet in the chest and continue fighting on, or, in especially bad cases, warrior-creatures that have both of the aforementioned traits...
Why the Lasgun is still being used
Although better known as a "flashlight", some players also call it "The AK-47 of the 41st Millennium", albeit ironically. Instead of being reliable, tough, relatively inaccurate and having a tendency to show up in the hands of just about everyone, it's reliable, common as fuck (like 100 for every human in the galaxy common), pretty damned tough, and accurate but that is only by 40k standards. ...So, yeah, I guess it is the AK of the 41st Millennium. It should be noted that the lasgun is stated to be able to destroy a slab of cement, which a .50 cal anti armour rifle would be able to do today. Although that could be because the Lasgun is placed on a slightly higher setting or it may be a different pattern of Lasgun. However, do also note that even the current-day AK-47 is capable of destroying cement (not reinforced concrete) slabs with a handful of shots, so make of that what you will. Except this was ferrocrete, no cement. The material used in large quantities to create bunkers. Ferrocrete is basically to cement what plasteel is to, well, steel.
Getting shot by a laser, even if you are protected, would at least flash a decent portion of the surface of what is hit into plasma. Explosively. So, most targets too tough to be penetrated by a lasgun would at least be stunned/stopped for a moment and shredded by a heavy stubber, special weapon, or true heavy weapon or stunlocked and gunned down by massed lasgun fire. So, it is actually pretty good in a utility sort of way given the enemies the Imperium faces. Furthermore, lasers damage just about anything to some degree when powerful enough. This means lasguns are among the few types of weapons capable of "eating" through armor. Games like to have armor being worked through via volume of fire, this does not actually work at all. But lasguns can due to causing damage through hitting atoms and subatomic particles. Which means a lasgun can theoretically kill anything in the universe...eventually.
The lasgun has very low recoil, especially in comparison to a bolter or even an autogun. More like a jolt than a kick, probably, due to sudden change in air pressure. The powerpack that the weapon uses can fire about eighty to a hundred/hundred-twenty shots before running empty and can be easily recharged through any standard Imperial power supply, direct sunlight, and even heat. A relatively common practice of Imperial Guard units cut off from supplies is to place their lasgun power packs in open fires, although this does lower the pack's lifespan considerably and is frowned upon (and stupid if you're cut off since now your only weapons won't last long).
The weapons are rather more useful in Dark Heresy than they are in the tabletop wargame, as their reliability, availability and plentiful ammunition become real considerations and they are rather more useful against the human foes that an agent of the Inquisition is likely to face.
Power packs for lasguns also vastly simplify a nightmare waiting to happen for ammunition logistics. Even if Autoguns were better in all ways than a lasgun, the Administratum would still use the lasgun for the power pack. Power packs, while not able to fit all sizes of lasgun apparently, can still be modified to fit, or be recharged in the middle of campaign. Especially important if you can't get any new supplies due to a variety of reasons (Enemy has orbital control, no one has your size caliber, ammunition expires, etc). This is important, since lasguns, the worst they can do if given the wrong size is not work. For an autogun, with the wide range and variety of possible ammunition sizes, the best that will happen is that you won't fire your weapon, the worse, is that the shooter dies, and more importantly the weapon is destroyed. This is a strategy already in use today: to simplify ammunition supply problems, all the guns fire the same cartridge. And ammunition logistics are already a nightmare today on a mere planetary scale where (at worst) thousands of soldiers are a couple thousand kilometres away from the nearest supply depot. These same standards are simply impossible to enforce in the Imperium for an army the size of trillions of soldiers spread all over the galaxy months if not years travel away from the nearest Forge World.
One last thing about Lasguns is that they can be used as last-ditch grenades by basically making the entire power pack empty into the gun without ever actually firing it. It turns the Lasgun into an explosive comparable in power to a krak grenade or melta charge, depending on how badly it manages to fuck up whatever it was thrown at. It can even fuck the shit of a Chaos Dreadnought who thought he was going to make some Guardsmen go squish, and instead gets a lasgun-bomb surprise to the face. (It should be noted that this happened to a dreadnought whose front armor was already cracked from being hit by anti-armor weapons, so no way your overloading lasgun is going to help against an undamaged one (so...grab your buddies and then go dreadnought hunting))
One must wonder, considering how ass-cheap power-packs and the part of the lasgun this power dumps everything into to make it go "boom" are (compared to things like melta bombs and probably krak grenades as well,) why doesn't the Imperium make standard-issue grenades like that? Seriously, imagine guard squads with grenades almost comparable to melta charges ( which are pretty much miniature nukes,) and remember that squads can get multiple assault grenade launchers. The answer is probably that the Techpriests would go completely apeshit for desecrating holy technology and try to secede. Again. Unless there's some threat that forces them to make such weaponry or some red-robed asshat can convince enough other red-robed asshats that it was totally an STC design of course. You mean like pointing out to them that since the foundation of their beliefs are that humanity already discovered everything and what humanity discovered and invented is holy, then if a human thinks of something then it must have been thought of in the Dark Age and is therefore right and holy and perfectly viable by Machine Cult doctrine?
Five counter-arguments to the lasgun-power-pack-grenade come readily to mind, discounting most guardsmen not being aware of this particular tactic.
- Firstly, the power pack's detonation timing is highly unpredictable, and as we all know,
anything that endangers an imperial infantryman will absolutely not be consideredonly the most fanatical, stupid, or just plain reckless Guardsmen would be willing to use it regularly. - Secondly, while a lasgun is pretty inexpensive in comparison to, say, a bolter, its power-packs are not as cheap to produce (they make up for it by being so easily recharged.) And only veteran soldiers tend to carry more than a small handful of packs; packs which said veterans probably looted off other guardsmen who didn't get to be veterans.
- Thirdly, the blast yield from a power pack is never described as being particularly strong. In the aforementioned example the soldier managed to open a dreadnought's faceplate just enough for the local flora to kill it, which sounds commensurate to a glancing hit, estimating the explosion closer to that of a krak grenade (S6) or maybe a little stronger. While still powerful when compared to regular old frag grenades, this is nothing like the famous melta bomb. Because surely the faceplate of a dreadnought is fragile. Like the viewports of a Baneblade (which tanked a krak missile in a novel). Easily killed Space Marine heroes are all the rage in the Imperium.
- A weapon, no matter how shitty, is still a soldier's baby. A soldier without his main weapon is generally a dead man, commissar or no, and the only time you would be forced to use your own, custom, probably personalized rifle if you live long enough to know this tactic, is in case of true emergency or imminent death. The same case that the first case of this ever being recorded happened. Which means only use this tactic when fighting any playable faction. Especially Necrons since it isn't like your lasgun will matter then anyway.
- Finally, in the instance where a Guardsman survives using his weapon and its magazine in such a reckless manner, he must then face the wrath of his superiors (If he survives the incident); the sheer number of Munitorum violations involved in using a lasgun and its ammo as a makeshift bomb are staggering (and while most alone would probably result in perfectly survivable corporal punishment, such as say being repeatedly rifle-stocked in the balls four dozen times while hanging upside down, all added up it's more pragmatic to just make the punishment execution to save some time.) Unless he manages to secure a new weapon beforehand of course. Well, not having a weapon is punished by execution (in case your lack of a gun is due to throwing it away to flee or something).
In all seriousness, a lasgun is a deadly weapon when in the hands of someone competent. As being an effective combat weapon goes, anything not too heavily armored, like Traitor Cultists, Eldar Guardians, Ork Boyz, Tyranid Gaunts, and other Imperial Guard style forces are bound to be ridden with Laser holes quickly and efficiently. The Vostroyan Firstborn, for example, are renown for their precision with their lasguns and rewarded with high kill counts against everything from Orks to traitors. Elysian Drop Troopers are similarly known for exceptional marksmanship bred via necessity wherein they maximize lethality with minimal shots. It is only against heavily armored foes that a Lasgun falters. Power armour is able to shrug off lasbolts like there's no tomorrow when they hit its reinforced ceramite layers. The wearer is not invulnerable, though: helmet lenses, articulations and joints are still vulnerable to a well-placed lasbolt and a point- or near-point-blank shot at maximum power from a lasgun can penetrate certain areas of a Space Marine's helmet (or armor in general) and turn his brains into impromptu house paint. Pray to the Emperor and get really lucky, you will take down even a Chaos Space Marine (or equivalent) with your humble lasgun. (though Space Marines are also known to die after being poked (stabbed) by enough pointy (sharp hard) sticks on occasion after all or being stomped on by enough human beings at once, plot willing.) And given the Imperial Guard's numbers they will always get some lucky shots, through sheer volume of fire. The closer you are to your target, the more penetration you get. Tough targets in 40K like to get up close and personal and by that point lasguns can go right through them to blast their squishy innards. Machines also get fucked over by lasers because it's electromagnetic (photons, duh).
In the end, a quote from Black Crusade (RPG) sums up the lasgun perfectly: "The Legionnaire that scoffs at a lasgun has not charged across an open field against a hundred of them." Of course, in Black Crusade a Legionnaire in power armor is almost impossible wound with a lasgun unless they score a Righteous Fury/Zealous Hatred ("critical hit"), which even then only causes minimal harm. But for representing Imperial Guard squads/platoons as enemies for Traitor Astartes player characters in Black Crusade, that is what the Horde rules are for, which allows representation of dozens of lasguns combining concentrated fire.. and becoming a very, very serious threat even for a Traitor Legionnaire.
Uses for the Lasgun
- Warming soup
- Cigarette lighter
- Changing TV channels
- Selling to buy a new weapon
- Pissing off Thunderhawk pilots
- Shining in enemies' eyes
- Throwing at people (may cause more damage than shooting it at them)
- Burning ants
- Paperweight
- Laser sight for a boltgun
- Aide during PotentiaPunctum presentations
- Light shows
- Laser tag for kids (who are probably more dangerous than the gun itself)
- Magic shows for kids
- Lighting candles on birthday cakes
- A Laser pointer
- Entertainment for your space-kitties
- Shooting bottles
- Hitting your officer's pipe (Warning, will result in BLAMing)
- Flashlight
- Substitute baseball bat
- Salvaged for actual useful stuff
- Horsie rides
- Chair
- Creating a makeshift rave
Other laser weapons
The lasgun also comes in carbine, pistol, bullpup, sniper ("long-las"), and light machine gun (the heavy lasgun, which so far seems to only exist in Black Library) - (Heavy laser is just a crew-fired multi laser) varieties, and the Imperium fields many other weapons based on the same technology, such as the hellgun (a powerful lasgun powered by a backpack power pack), the mighty lascannon (mighty being relative... SPESS MEHREENS can equip it), the even bigger volcano cannon and turbo-laser, the even bigger Defense Laser, and the bigger still laser weapons mounted on starships. Must be a different type, though, because a broadside from a Retribution class battleship can devastate half a continent depending on the calcs. A single barrage from an Imperator class Titan can devastate an entire city with weapons as strong as modern day nukes. Keep in mind how large an Imperial city is. So, far stronger than modern nukes.
Oh, and multilasers.
Laspistol
See main page, Laspistol
Lasgun
You know'em, you love'em. There really isn't a point in repeating what has already been said since you are on a page talking about this wonderful piece of Imperial equipment other then than putting it in the Lasgun family. Of course there are certain modifications that may breach the line on what may count as a Lasgun. But overall, it is cheap, effective and put a lovely little dent to most light infantry contrary to popular belief.
Just don't try and attempt go all Leeroy Jenkins on this thing. The Lasgun is a light assault weapon, not a Titan-busting Volcano Cannon.
| Edition | Range | Type | S | AP | Damage | Abilities |
|---|---|---|---|---|---|---|
| 7th | 24" | Rapid Fire | 3 | - | N/A | - |
| 8th | 24" | Rapid Fire 1 | 3 | 0 | 1 | - |
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Cadian
Hotshot Laspistol
See main page, Hellpistol
The Hotshot Lasgun's little brother, also known as Hellpistol (although there do remain some canon conflict about these two weapons designation). Hotshot Laspistols are typically hand-crafted, rather than mass-produced in factories, and many of them are hundreds of years old and have acquired histories over the course of centuries of use in combat. Unless otherwise specified, a Hotshot Laspistol remains the property of the Departmento Munitorum, though an individual can be awarded one for heroic deeds. A Hotshot Laspistol fires a higher-intensity shot than a laspistol, therefore, despite its higher penetration it will cauterize the wound it causes and prevents too much blood from being shed. For this reason, Hotshot Laspistol are preferred for use as execution weapons for officers and commissars, as a shot to the condemned soldier's head will prevent any blood from staining their uniform.
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Tempestus Scion
Hotshot Lasgun
See main page, Hellgun
A variant of the Lasgun, also known by the far cooler name "Hellgun" (although there do remain some canon conflict about these two weapons designations since they have different art, different models, and are used by different units in both the lore and in the models...so yeah, probably totally different things), the Hotshot Lasgun and Hotshot Laspistol are weapons used primarily by the Stormtroopers (and presumably other arms of the Imperial war machine). In some canon sources, these are juiced-up versions of the Lasgun charge pack inside a normal Lasgun, or in other canon sources, the entire weapon has a beefier build with better conduits and optics to survive the prolonged increased strain of a higher power throughput. They are designed to be used by elite troops or officers, who are generally better shots. Instead of the Hellgun's design approach of using lots of batteries and a heavy-duty build to attain higher cyclic fire rates, Hotshots use a super-concentrated laser blast to achieve the same kind of armor-penetrating power.
| Edition | Range | Type | S | AP | Damage | Abilities |
|---|---|---|---|---|---|---|
| 7th | 18" | Rapid Fire | 3 | 3 | N/A | - |
| 8th | 18" | Rapid Fire 1 | 3 | -2 | 1 | - |
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Tempestus Scion
Hotshot Volley Gun
Another variation of the Hotshot category of Lasguns. These weapons are borne into battle by Tempestus Scions to deal with armored enemy infantry. The Hot-Shot Volley Gun is a larger version of the Hot-Shot Lasgun that "incorporates penitent-class heat sink arrays" which means that they "can maintain a punishing rate of high powered fire".
Think of them as a fully automatic LMG version of the regular old Hotshot Lasgun. As you can imagine, the sheer amount of Dakka means that they are more likely to be situated within the heavy weapons category then the normal Hotshot Lasguns. They are known to fire with a distinctive spitting howl.
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Tempestus Scion
Mining Laser
Mining Laser is not formally a weapon, but a tool for breaching tunnels in the mining process. In some cases though the Mining Laser can be used as a weapon, often by Genestealer Cults. For example, Dvarlock pattern Mining Laser, founded and identified by Tempestor Gulack of the Kappic Eagles have been modified so it can blast the hole through a meters-thick bulkhead with a single pull of a trigger. It also features three hand-grips. indicating its use in combination with a tertia pattern servo-arm (or the extra arms of an Acolyte Hybrid).
There is also the Heavy Mining Laser which is a heavier variant of the standard version, used on Goliath Rockgrinders (More can be read below). Although to be honest, it is only 'heavy' because it is on a turreted mount, other than that there is very little difference between the Heavy Mining Laser and the regular old Mining Laser.
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Neophyte Hybrid
Long-Las
In the good old days the Imperial sniper rifle was the poorly named 'needle rifle' which was in fact a kind of laser weapon. Well, partly. It had two parts to each shot. It fired a narrow beam laser to burn through armor, and then it fired a 'needle' bullet; a spike of some kind of metal filled with horribly poisonous toxins. With the armor removed first, the spiky bit all but ensured a kill if you hit, spurting deadly death juice into your unfortunate body. Sadly they weren't especially well conceived weapons (hitting the same spot with two different weapons, one that responds to wind and gravity, and the other that doesn't is something of a challenge) so they've pretty much been written out of the setting these days as being too expensive for regular use. Now the term "sniper rifle" is used fairly loosely in the Imperium; many sniper rifles are simply over-powered lasguns called long-las rifles, while many others (such as those used by Space Marine Scouts) are high-velocity slug-throwers which have more in common with autoguns than they do with energy weapons. Then there are other more exotic variants firing poisoned darts or even stranger payloads, such as the aforementioned needle rifle (which Ratlings still prefer). All of these variants have pretty much the same effect on the target, unless you play older editions or use special characters who have rules that say otherwise. Or play Dark Heresy.
However, since you are on the Long-Las category, we might as well talk about it. The Long-Las is a sniper variation of the Lasgun with a much longer barrel for increased range and accuracy, and also to prevent overheating. However the barrel makes a Long-Las up to twice as long as a standard Lasgun and thus difficult to use in close quarters.
Within the Imperial Guard the Long-Las, formerly known as the Sniper Variant Lasgun, is issued only to those Guardsmen with the necessary marksmanship skills and knowledge in stealth and scouting operations. It uses the XC 52/3 strengthened barrel, longer and thinner than normal models, and lacks a charge setting slider, instead using hotshot power packs. It's also much quieter than other lasguns and features a flash suppressor to dampen the revealing flashes of its shots. However the increased wear on the barrel from using the overpowered energy packs means more frequent barrel changes than is usually required for normal lasguns.
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Cadian
Lascarbine
During the Great Crusade the Lascarbine was the great grandfather of the Lasgun. Basically the same weapon as the Lasgun in a smaller package. They were standard issue among the Imperial Army and Solar Auxilla.
In modern WH40k, a Lascarbine is designed for use by special operations units and is usually employed by Drop Troopers or scout units of the Imperial Guard such as the Elysian Drop Troops.
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Catachan
Auxilia Lasrifle
The Auxilia lasrifles were the primary weapon of the Solar Auxilia during the Great Crusade and Horus heresy eras. And as benefiting weapons from a time when Imperial Technology had not yet sunk into the abyss, they have better range compared to their inferior knockoffs. These weapons have the option of taking Blast-chargers, which turns the lasrifle into a miniature lascannon, though on the roll of 1 the gun explodes in its operator's hands, preventing the player from using them for the remainder of the game. They also come standard with Collimators, which switch out Rapid Fire for Heavy 2. Making any opponent think twice about about charging a squad of Solar Auxilia. As if a Super Heavy tank as a Dedicated Transport wasn't enough reason to stay out of range.
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Solar Auxilia
Blast Pistol
Not to be confused with the Phosphor Blast Pistol, another 30k era weapon that fires completely different rounds.
Basically a souped-up las-pistol that explodes in the user's hand. Their description makes them seem like laser revolvers used by officers of the Solar Auxilla. To mirror when an officer during the 19th century was issued a sidearm. Giving him a better gun than the line troops who had to use leaver and bolt actions. Which isn't the case here.
These bespoke weapons like the Hotshot Laspistol and Hellpistol were able to fire only a handful of shots before reloading, but their damage output rivals that of arcane Volkite Weaponry. Due to this, Blast Pistols were seen as an emblem of wealth and prestige, and many were works of art in their own right, and thus they also became a widely used form of decoration and reward for extreme gallantry and commendation within the Solar Auxilia regiments.
On the table top. Blast Pistols are S5 Las-pistols with Twin Linked and Gets-Hot. Archaeotech and Plasma pistols are more useful then these things.
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Solar Auxilia
Digital Lasers/Digital Weapons
These are actually melee weapons. However there isn't really anywhere else to put them. In 40k they are exclusively made by Jokaero. During the Great Crusade and Horus Heresy they are weapons of unknown Xenos origin. This section describes how the Imperium at large uses them.
Digital weapons are best described as a small laser used by Space Marine officers. It allows them to re-roll one failed hit during the Assault/Fight Phase. Which is decent, However it isn't anywhere near as cool when their used in Black Library books or the weapons stated to be used by the Jokaero. Only the Xenos monkies have them on the table top in 8th edition.
30k Digital Lasers are as usual better than the 40k version. Rather than just Space Marines, Inquisitors and the occasional gun/chain/power sword toting hero. Every officer had access to them. They are short ranged but deadly weapons that are "small enough to be concealed in a ring, gauntlet, sword hilt or helm." So they should be as strong as a single Hot Shot Lasgun, Lasrifle or Las-Lock beam.
In the Horus Heresy game a Digital Laser gives the model one additional attack. So the officer doesn't have to give up their sole ranged weapon for an extra melee hit. One would assume either weapon would also allow an extra ranged attack with the same strength and AP as a Hot-Shot Lasgun or Archaeotech Pistol. Like how the Servo Harness gives Techmarines extra ranged and melee weapons. However Games Workshop and Forge World aren't nice enough to give players an option that would be useful in more than one situation. Without making them pay extra real life money for it first.
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Jokaero Weaponsmith
Las-Lock
Las-lock is like a granddad to "modern" Lasgun. While very few Guard Regiments still use it in-universe in 40k (see Only War by FFG), the Las-Lock is popular with the Mechanicum in 30k. Tech Thralls are thus far the only known Mechanicum troops to carry las-weapons, but oh boy, aren't they numerous. Las-locks sacrifice rate of fire and range for more damage per shot, making it a worse version of the Hot-Shot lasgun with higher Strength, but with miserable AP of 6 and 1 shot max.
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Tech Thrall
Mitralock
There is also the Mitralock, a laser shotgun with reduced range. Both have the option to upgrade to Induction chargers increasing their shots to two.(represented as Assault 2 in game.) While still allowing them to Assault with no penalty. This turns them into a high risk unit for any opponent dumb enough to charge them.
In terms of tabletop, the Mitralock is the Scattergun of the Las Family. It is an 8" range Las-lock, but it gains Shred. It also has Induction Chargers which is an optional attachment to both Las-locks AND Mitra-locks (HH3, p. 221) it upgrades them to Assault 2.
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Tech Thrall
Lascutter
Lascutters are a powerful but extremely unwieldy type of Laser Weapon. Originally industrial tools used for cutting through armored bulkheads and dense ores, these weapons make use of disruption field-assisted short range laser arcs. They were later utilized for warfare, being used in sieges where they were able to breach enemy fortifications and if necessary become devastating close-quarters weapons. On the table top, these thing suck. Only Breachers can take them. The Cumbersome rule reduces the model's WS1 and can only make a single attack. Take Graviton guns instead.
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Legion Breacher
Lightning Gun
Despite the name, Lightning Guns are a type of laser weapons used by the AdMech. Whilst they do use electromagnetism, most of the killing power is from the pew pew lasers. Lightning Guns are Great Crusade era weapons used by various Adeptus Mechanicus troops, most notably Thallax.
This aptly named weapon takes the form of a baroquely designed carbine connected to a micro-reactor or power core. It fires an ionizing las-beam along with a powerful phased discharge of electromagnetic particles. The ensuing effect makes the weapon able to overload mechanical targets in addition to its effectiveness against organic enemies.
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Thallax
Multilasers
See main page, Multilasers.
The Multilaser is basically just a Hellgun that's been modded for more Dakka, being a pretty good weapon against most non- to lightly-armored targets (infantry, Taurox-equivalents, skimmers, etc.).
Heavy Mining Laser
The aforementioned Heavy Mining Laser. As previously mentioned, it is basically a Mining Laser on a turret. Like its smaller brother, the Heavy Mining Laser is used primarily to bore through rock and other quarry within Mining and Forge Worlds of the Imperium. However it can also be used to cleanly bore through the side armor of a Leman Russ and a Space Marine if needed.
The Genestealer Cults have exploited its power because of this. The only difference between the regular Mining Laser and the Heavy Mining Laser is in its power supply. The regular Mining Laser carries its own portable power supply which makes it mobile but at the cost of a shorter battery life (eg: less 'shots') and a shorter effective range. The Heavy Mining Laser on the other hand, is connected to a much larger and thus, powerful power supply which allows for a longer battery life and a longer range.
It is often mounted on the Goliath Rockgrinder, but it can also be mounted on the Achilles Ridgerunner and the Wolfquad.
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Golaith Rockgrinder
Lascannon
See main page, Lascannon.
These are the main Imperial anti-tank weapon (Heavy1 72" S9 AP2 for D6), and they are mounted on EVERYTHING.
Corve Las-Pulser
The Corve Las-Pulser is a type of Laser Weapon used by the Adeptus Custodes. They are the giant Lascannon mounted on top of the giant Dreadnought-like spear. It was equipped to the Dreadspear of the Custodes Contemptor-Achillus class Dreadnought.
The Corve is a 36" S9 AP2 Heavy D3 weapon. It is an upgrade for the Agamatus jetbikes and found as part of the Contemptor-Achillus's Dreadspear, and most of the reason for it's 40 point upgrade cost. The Pulsar is one of the few weapons that Custodes have as a counterpart to Lascannons.
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Contemptor Achillus -
Agamatus Jetbike
Las-Ripper
Essentially a weaker version of the Las-Talon.
A Las-Ripper is a type of heavy Imperial Laser Weapon usually deployed on the Primaris Space Marines' Astraeus Super-Heavy Grav Tank. Las-Rippers are used as sponson weapons on Astraeus grav tanks, where they serve as the vehicle's standard anti-personnel weapons for close and messy encounters.
In terms of crunch, as previously aforementioned, the Las-Rippers are a weaker version of the Las-Talon. Although it is not a bad weapon per se, it suffers from the fact that there are much better weapons that the Astraeus could be equipped with.
Most often, the Las-Ripper is replaced with the more powerful Plasma Eradicators. This have got to do with the fact that the Plasma Eradicators are understandable more powerful per shot, but what is unusual is that the Eradicators have more range and is cheaper than the Las-Ripper of all things.
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Alternate View
Las-Talon
One of the primary weapons of the Repulsor and a discount Lascannon.
The Las-talon is a specialized type of Laser Weapon that can only be found on both the Stormhawk Interceptor air superiority fighter used by the Adeptus Astartes and the Primaris Space Marine Repulsor armored transport.
The Las-talon fires two potent blasts of laser energy in rapid succession, ensuring a clean kill against even the heaviest armored targets. Unlike other laser weapons, the Las-talon is relatively short-ranged, with its damage heavily reduced at great range.
And as you know, it is basically the big brother of the Las-Ripper.
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Primaris Repulsor
Laser Destroyer
The Laser Destroyer is an Imperial laser weapon mounted primarily on the Destroyer Tank Hunter, capable of destroying enemy tanks from long range. The Laser Destroyer however is a highly-complex system which all but a few Forge Worlds can no longer reproduce; even those who can create new ones must hand-craft each one through a painstakingly slow process. The result has been that these weapons and the vehicles which use them have become incredibly rare amongst the Imperial Guard. The chance of receiving any replacement for lost or destroyed models is very slim, often leading to recovered tank destroyers instead being fitted with another weapon.
During the invasion of Armageddon, though, a number of Chimeras were refitted with Laser Destroyers and re-designated APDS-6a 'Defenders' as an effective stop-gap measure against the Orks.
Neutron Laser
A Neutron Laser is a heavy weapon utilized by the forces of Adeptus Mechanicus' Skitarii Legions as a primary weapon for Onager Dunecrawlers. A Neutron Laser is the last word in battlefield anti-tank weaponry.
With a stabilised neutronic coil arc reactor as its power source, a Neutron Laser is able to fire a beam so devastating that it not only is able to punch through the thickest of armour, but also sends a blast wave of electromagnetic energy that scrambles circuits and synapses alike when it strikes its target.
It doesn't seem to suffer as much of a backfire feedback that usually plagues its larger brother. So that's a plus.
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Onager Dunecrawler
Arachnus Blaze Cannon
The Arachnus Blaze Cannon is a type of Laser Weapon used by the Adeptus Custodes. This weapon was a development of standard Imperial las-technology, but with built in esoteric and powerful components which could never be replicated en masse.
The Blaze Cannon is mounted on the Coronus Grav Carrier.
On tabletop they are basically the bastard offspring of Multi-lasers and Lascannons, they have two firing modes. One is Burst for infantry shredding, the other is Concentrated for Vehicle killing with AP1 and Exoshock, which gives you an automatic second Penetrating hit which ignores cover saves on a 4+ after you score one (so you roll to hit, roll to penetrate, enemy rolls invulnerable/cover, and only then...)
The Blaze Cannon itself is a S6 AP5 Heavy Bolter, or 48" S8AP1 Heavy 1, Exoshock: In all honesty, the Burst mode is rather shitty, but Concentrated is essentially a Lascannon with nasty special rules.
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Coronus Grav-Carrier
Arachnus Heavy Blaze Cannon
A larger version known as the Arachnus Heavy Blaze Cannon also exist.
This time it is mounted on the Caladius Annihilator and it is basically a twin-linked Lascannon on steroids.
On tabletop they are basically the bastard offspring of Multi-lasers and Lascannons, they have two firing modes. One is Burst for infantry shredding, the other is Concentrated for Vehicle killing with AP1 and Exoshock, which gives you an automatic second Penetrating hit which ignores cover saves on a 4+ after you score one (so you roll to hit, roll to penetrate, enemy rolls invulnerable/cover, and only then...)
The Heavy Blaze Cannon itself is a 48" S8 AP3 Heavy 4, or 72" S10 AP1 Heavy 1, Exoshock: Optional turret replacement for the Caladius.
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Caladius Annihilator
Arachnus Storm Cannon
The big honcho mounted only on the biggest of Dreadnought walkers.
The Arachnus Storm Cannon is a large gatling-style Laser Weapon used by the Adeptus Custodes. It is most typically mounted on the Telemon Heavy Dreadnought. The Golden Bananas just wanted to have an oversized Multi-Laser and the Emprah delivereth.
On tabletop, the Storm Cannon is a 48" S7 AP3 Heavy 7, or 72" S9 AP1 Heavy 2, Exoshock: the Telemon's big Gatling gun and perhaps the most versatile of the Arachnus weapons. This is a must take if you are facing armies with a large amount of vehicles.
Helfrost weapons
Laser cooling is actually a thing. See main page, Helfrost Weaponry
Laser Destroyer Array
Laser Destroyer Arrays are a special type of lascannon array. Instead of firing in a single, solid blast the laser destroyer would fire short pulses microseconds apart from its various barrels, acting as a sort of long-ranged drill. On the plus side this means they're more destructive (never a bad thing) as it allowed them to bore through everything, on the downside it's apparently more of a pain in the ass to fire and reload them, going by their tabletop stats and they're nowhere near as portable. Note that despite sharing the name, they are not the same as laser destroyers.
In 7th edition (and Horus Heresy) this gave you a single lascannon shot which was Ordnance instead of Heavy and AP 1 instead of 2. It dealt with vehicles better but similar lascannon arrays fired 2 shots instead of the one (both are twin-linked) so if you had to decide on the two then you had to make a choice, quality hits or quantity of hits? There was a way to up the shot count, but only if you took a Vindicator Tank Destroyer. If you stayed motionless and/or declared to overcharge it after remaining motionless, you could add +1/+2 to its shots respectively, and after it fired you'd do the equivalent of a Gets Hot roll. In practical terms if you were playing 40k you were free to remove whatever vehicle your opponent fielded that you didn't like, whereas if you were playing Horus Heresy you'd wish Flare Shields weren't a thing as you still couldn't kill that Spartan.
In 8th edition the Laser destroyer is hilariously powerful, being S 12, AP -4, D6 damage but before you roll for damage, roll a D6. On a 1-2, it's still just D6 damage. On a 3-5, it's 2D6 and on a 6, it's 3D6. Ever wanted to cripple a Knight, Land Raider, monster or just remove that one character who accidentally got a little too close in only one shot? Now you can. It's also surprisingly cheap meaning you can spam the fuckers and potentially forget about taking lascannons entirely. Also hilarious is that the Rapier Laser Destroyer has actual combat stats, and not the kind that are explained away via its crew steering it into the enemy, but literal stats as somehow the thing attempts to hurt the enemy by poking it with its barrels (presumably). Despite being (technically) a vehicle its pokes are also weaker than the Guardsmen who push it around, being S3 whereas these macho-men are S4.
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Rapier variant
Superheavy Laser Weapons
See main page, Superheavy Laser Weapons
Properties of a lasgun
It's easy to imagine being hit with a lasgun would be like having a hole burned into you like an ant being burned by a magnifying glass. That, of course, is not nearly grimdark enough to be the truth.
A military DEW (or Directed Energy Weapon since military forces love TLAs (Three-Letter Acronyms)) comes in several different types, from microwave weapons which are mostly used to short out electronics but can also be used to cause intense pain by microwaving the surface of the skin (as is the case with the Active Denial System), to Electrolasers which use lasers to ionize the air into a semi-superconductive channel, allowing an electrical current to be projected between two points like a glorified (albeit high-power) taser. This may in fact is likely how necron Tesla weapons work, but that is beside the point. A lasgun however is most similar to a pulsed energy laser. A pulsed laser works by imparting so much energy to an area so fast, that it turns into plasma and explodes. Modern versions create a pressure wave strong enough to stun and knock a person out (termed "Pulsed Energy Projectile), but they are less then-lethal weapons that don't penetrate things very well by design, while the lasgun is not.
Being hit with a lasgun would (could) look and feel more like you were hit by a concussion grenade held up to your chest (which would messily kill you, like a lasgun would). You would see a bright flash of light as your skin or clothing vaporized into plasma, much like a high-end camera flash going next to the wound. Higher-power laser weapons might cause enough of an explosion to blow you back and maybe knock you unconscious, or if you got hit by one of the Lasgun's anti-tank big brothers, vaporize you outright turning you into an impromptu plasma grenade for the rest of your squad to deal with. The explosion would create enough hydrostatic pressure to likely scramble your internal organs and maybe snapping your bones in parts of your body distant from the explosion. So, shooting someone's cover with a lascannon is actually a good idea in real life. Then your buddies can just murderize everyone who had been hiding behind it (on their asses half dead with their armor destroyed).
However, if the lasgun hit something like armor, or even clothing it might induce an explosion only on the surface of the armor leaving the rest of you safe (except for the whole "the stuff you were wearing blew up" part, which would still wreck your body), though most assuredly stunned and dazzled from the plasma explosion (in the sense of "you're stunned and dazzled by the pearly gates after the plasma explosion"). This explains why the Lasgun has a AP of only - shit. A Bolter's bolts, on the other hand, penetrate the exterior and then explode inside the target, meaning it can deal with armor and tough alien targets like Orks much easier, since you're effectively ignoring the armor on anything the mass-reactive warhead can punch through. The lasgun is clearly nothing to sneeze at; it's just that the vast majority of the Imperium's more exotic enemies are capable of taking that kind of punishment most of the time and still keep on fighting. On the other hand, a lasgun is not a Hammer's Slammers plasma weapon. It does not impart all of its energy into the first significant object it hits. It keeps going. Don't forget that a Lasgun's power level can be changed with a switch of a nob (depending on what pattern of Lasgun you get of course), meaning that you could theoretically have Lasguns powerful enough to punch Ferrocrete (AKA super concrete) and melt power armor at the expense of ruining the barrel, power supply and any relationship with your local Techpriest adept. Because, again, this is a laser, not Hammer's Slammers plasma.
Now, if you want what actually happens when shot by a lasgun instead of a non-lethal modern version, it's this: the plasma explosion destroys a large area of your clothing or light armor, breaks your rips, and ruptures your organs and the heat causes your skin and some other fluids under the impact point to also detonate to a significantly less intense degree, easily killing you if you weren't already dead (and if it doesn't kill you, heat trauma will). It also doesn't impart all its energy unless the target is durable enough. Something weaker than flak armor is not durable enough (or anything at close range to a lasgun, really) and the laser in the case of inferior armor will pass through and all the organs and crap near the beam will also explosively flash into plasma and everything near that will explosively flash-vaporize. You get the idea. This is a damn powerful weapon against anything that isn't either a super alien or a super human (or Egyptian zombie robot pirate). Or anything that isn't more heavily armored than infantry have any right to be that doesn't involve super-tech. Basically, if your shot by a lasgun and you're not one of the playable factions, you're fucked. If you're hit but not fucked, congratulations, you are now either off balance or knocked on your ass and probably an easy target for any Guardsman wanting to finish you or, at best, you now have badly damaged armor and another shot will kill you and you still have to get off your ass and not get shot while doing it.
However, all that is based on the previously mentioned less than lethal lasers, which are specifically designed that way on purpose; more lethal laser weapons, while possible with 21st century technology, require massive amounts of power to function properly- and unlike 40k, we don't have the equivalent of power packs to contain the energy needed for a man-portable form to work or even something that could be mounted on a tank. The closest thing to those would be ship-mounted lasers designed specifically for shooting down missiles or aircraft, and even those have rarely left the prototype stage due to the energy issue and thermal blooming (described further below). Except in America, in which they are equipped on ships and the American navy also is using a few anti-satellite lasers on some ships.
A laser can easily be designed to maximize impact or penetration, and autogun bullets, which could likely go right through many parts of you, also have AP - anyway (it's bullets vs super space monsters, what did you expect). A theory more in line with the stated effects of a lasgun shot is that it would use multiple insanely rapid micro pulses to BORE THROUGH light infantry-grade armour, clothes and flesh to reach internal organs. Imagine getting drilled into by hundreds of tiny explosions, all within the span of milliseconds (more like hundredths or thousandths of a millisecond). This would leave wound very similar to the ones described in the Uplifting Primer, nasty burnt holes (and the aforementioned explosive flash-vaporization and micro plasma explosion effects in a wide area around the penetrated area). According to the Regimental Standard's "Field-Dressing a Lasgun Wound" article, the laser's heat cauterizes any wounds left by the shot (which is scientifically incorrect as the explosive flash-vaporization would prevent all but a minuscule amount of random cauterization and the only way a cauterized would could be present is if the laser was too weak to penetrate a human body in the first place since it wouldn't even be hot enough to evaporate water), but the subsequent swelling can still be lethal if it occurs in or near a vital organ. Most likely the Regimental Standard article was written by an idiot who not only didn't know lasgun lore but also didn't know basic science but we can pass it off as Imperial propaganda to encourage Guardsmen to believe they won't die if shot by a lasgun unless they're just unlucky. OR the article assumes you were shot through your flak armor and so all but a tiny amount of the laser's energy had already been absorbed by your armor, saving your life but still leaving a serious wound in need of dressing before it can cripple or kill you anyway. By the way, did you know the lasgun is basically a radiation ray gun? Didn't you know the electromagnetic spectrum is radiation? So, could you kill someone with severe radiation poisoning if they do survive being shot by a lasgun?
You've noticed that a lot of a lasguns damage works via energy and heat exchange. This further explains it's AP of -, since most of the heavy armor that the Imperium uses are are based on ceramics, which are legendary for how well they absorb heat. The Space shuttle uses the stuff to allow reentry and presumable other heat resistant materials are used in other races armor since if your the Tau (crystalline armor screwing up concentrated light) or even Eldar (psychic play-doe bullshit), you know you're going to have to fight laser weapons at some point.
While the lasgun is portrayed in some media as having recoil, it doesn't in any true sense of the term. There might be a slight jerk on the barrel from the air pressure differential created by melting a hole through the air, a la a thunderclap, but the effects would be much more pronounced on the target (since there's no direct exchange of kinetic energy, the recoil can be zero, while there is a noticeable impact.) It might make a loud "crack" noise, due to Compton scattering, if it is fired in atmosphere and an abundant source of electrons is available (such as from the gun itself, if it is design appropriately). It should also be noted that at long range, if you were shot with one, there would be a substantial delay between the shot hitting you and you actually hearing the noise, making it an effective sniper's weapon. The second most common counterargument to this is that you would be able to follow the beam back to the sniper, but remember: you don't see the beam. It's too bright for you to be able to see it clearly, and you're going to be flashblinded by both the plasma explosion and the laser itself, if it's in a visible spectrum. Which it doesn't have to be. In fact, since Imperial lasgun is described as firing blue or white beams, the laser itself is likely ultraviolet, meaning there would be some brightness as it carved through the air, but not as much as a high-power laser backscattering into your eyes and giving you an impromptu round of Lasik.
Coming to that, the continued use of a lasgun is probably going to render you blind. Even though it has a baffling tip that not only can protect the barrel but also shelter the shooter from the flash (and even direct that at the enemy for extra fuck you). Remember, this is a gun that shoots a whole bunch of light to do damage. It's going to be even harder on your retinas, even if you're not the one being hit by it. After all, just because you can't see UV light doesn't mean it's not bouncing around your eyeballs-this is why UV protection in sunglasses is such a big deal, and why your eyes sometimes hurt when you step outside on an overcast day. There's still light there, and it's still fucking with your very easily damaged optics. So unless the Departmento Munitorum issues some kind of protective eyewear or contacts to the Guardsmen (and don't kid yourself, this is 40K. They don't, except they usually do as the majority of regiments who wear helmets have visors, goggles, or gas masks, all of which can easily be made UV protective), their vision is going to get worse and worse over time, until they finally go blind. Fortunately, this would take about six months to a year of exposure of combat level conditions, or one apocalypse battle on a gunline, and most Guardsmen are not going to live that long on the battlefields of the 41st Millennium, and if do live that like then you're an elite soldier (or commissar/commander) worth the laser eye surgery to keep fighting since you're now worth many times what a normal guardsmen is. Or you manage to buy a cheap pair of shades at your troop ship's market, which are actually pretty common even then.
Except that you don't have to worry about laser back scatter or (to a lesser extent) lasers sucking at range. Lasers of sufficient power don't reflect. As in at all. Their light and energy is basically absorbed by the surrounding atmosphere, a process known as thermal bloom; it the real world, this significantly limits the power of any laser weapon since other potential workarounds are currently impossible to implement. So the only light you'd have to worry about is the plasma flash of the impact and beam (if present). Also, lasers that can blast holes in to you may suffer from dust or distortion effects, but non-vacuum frequency lasers will get through air well enough simply on the basis that air is much much less dense than what it is intended to actually bore through. Also adaptive optics can at least partially mitigate said effect. As far as inverse square law goes, lasers are COHESIVE beams, and can easily be focused and stay focused well within firing range, even for typical sniper ranges, if aperture is large enough and/or wavelength is short enough to counter diffraction (UV is very short).
TL, DR: People disagree but it's not fun.
Too short, want more? Go here.
Why the Lasgun doesn't suck (an alternate take)
The purpose of the primary infantry weapon is not to take out everything that the infantryman might face. It's to provide volume of fire and self defense from other infantry. As today the average infantry man is equipped with an assault rifle that is not capable of piercing through light armor and up, nor is intended to. That's why in infantry squads you have infantry support weapons, like machine guns, mortars, rocket launchers, grenade launchers, anti materiel rifles etc. An infantry squad is supposed to take on hard targets with its support weapons where light armed troopers provide cover and logistic support. Also they are supposed to call in heavy support from artillery/air/tanks etc.
The Imperial Guard is fully equipped to handle harder targets with a variety of powerful infantry support weapons (plasma rifles, missile launchers etc) and a huge selection of heavy fire support from lascannons to Leman Russes.
In this context the lasgun is a fantastic weapon, far superior of the today assault rifle even considering the battlefield differences. The lasgun is extremely rugged, reliable and will require almost zero training because it has no moving part or recoil. The "no recoil" part being extremely important, because it means that untrained troops will still be able to put down relatively accurate full auto fire, a practical impossibility with today guns. Lasgun fire will rape non-armored or lightly armored infantry and still pose a threat to medium armored infantry, not to mention it will absolutely destroy unarmored vehicles. A bullet can cause virtually no damage to an M02.018 truck, but a lasgun bolt will cripple it.
The logistical ability of giving hundreds of shots to every single infantry man, in the form of compact, standard and rechargeable power packs is the ultimate dream of every army. The level of flexibility that this allows is incredible and is unmatched by virtually any other infantry weapon in the 40k universe. And remember: "amateurs talk about tactics, professionals talk about logistics".
The lasgun is such an incredibly flexible weapon that it could be even modified into firing more powerful shots, still retaining part compatibility and power source (therefore logistical chain). So it's well suited for the lowly grunt and the special forces operatives, that will also be able to use it's superior training and physical fitness to carry literally THOUSANDS of shots worth of power packs. This will enable all sort of long range military operations deep in enemy territory and far from supply lines that we can't even think of today.
And yes, in 40k everyone and their mom has at the very least carapace-grade armor that will offer a decent grade of protection from lasgun shots (and that's not counting the fact that even carapace armour could be rather reliably pierced by lasgun's beams, albeit this would generally require a guardsman to close to about 100 meters distance to his target as opposed to lasgun's 400-500 meters effective range against infantry, donning only light flak vests and regular steel helmets). But that's not a weakness of the whole lasgun concept. Far from it. It's the ultimate victory of it, because it means that your enemy has to spend a shitload of money to put every one of his soldiers in expensive top grade armor just to have any hope not them to be instantly destroyed by your endless stream of dead accurate full auto lasgun fire.
On that note, we would like to also note something. Since lasguns have instantaneous hits, they, when massed, make for a good anti air weapon. Something that is lightly Armored will soon be chewed up by the lasfire. This is more heavily covered below. As well, it can kill even those top notch armors. If fired into the eyepiece of a space Marine, you can actually bring him down. In addition, due to the ability to pick up any other version and with a few seconds be able to use it, special troops are not hard to come by. Also, note that massed fire on anything is bound to start dealing damage. If one has a couple dozen squads of Guardsmen focus fire on a squad of Space Marines, they may be disabled from lasgun fire hitting vital zones. In many books, massed lasfire is able to chew on (space marine) armour regardless of hitting hitting exposed parts. This is realistic because las weapons will transfer a lot of energy to the armor material. This means that the armor would rapidly overheat to the point of cooking the marine inside. To avoid this the armor is probably designed to ablate, meaning that the upper coat of the armor itself will vaporize upon being shot to dissipate heat. Once the ablative coat is expended, then even heavy armor would start to take damage from lasguns. However, it does require a decently large group of the bastards, as the average lasgun comes in at... 220 rpm. Preeety slow. Only 3-4 shots per second. This would also be exponentially less effective against bulkier armor like terminator armor because of higher thermal inertia and virtually useless against big armored vehicles.
Compared to other small arms
The lasgun is arguably one of the least powerful weapons stat-wise, on par with the autogun in the tabletop. This is why it is often compared to a flashlight, highlighting how inadequate it seems in the frightening battlefields of the 41st millennium. We already debunked this, showing how the lasgun is a powerful, flexible weapon which would provide effective firepower to the guardsmen in support of heavier weapons and squad tactics. But would be possible for the Imperium to provide better guns to the average soldier? Is really the lasgun adoption a byproduct of the incompetence of the Mechanicum to provide more powerful weapons? Are the enemies of mankind better armed? We will compare the lasgun to other small arms not considering the production costs and availabililty but focusing on battlefield praticality.
Imperial Boltguns
The imperial boltgun is a very powerful weapon and it's the ideal tool in the hand of the augmented post human. The space marine fulfills a heavy infantry/shock troop(/light armour) hybrid role and such a brutally powerful weapon is very well suited for him. But without the superhuman strength to carry ammunition and the superior training, reflexes and accuracy of a space marine, the recoil-heavy and relatively low capacity boltgun is a poor tool for the average human soldier. This is consistent with the fluff, where human-sized boltguns are available but see very limited adoption.
Imperial Plasma Gun/Plasma
The plasma gun is very powerful, but even without the little "exploding" problem, the practical rate of fire is probably quite limited before overheating. The plasma gun is bulky and complex to field and mantain. The ability to fry everything up to heavy armor is nice but completely wasted on more numerous targets like cultists, tyranids, rebels, etc. The recoil also is reported to kick like hell. The monstrous power output is bound to have logistical repercussions on magazine capacity, production, storage etc. The plasma gun is a very useful force multiplier, with the peculiar ability to fulfill a wide variety of roles. But a general issued weapon is not one of them.
Hotshot weapons
The first step up from Lasguns with penetration close enough to Bolters. Seems like a good idea right? Well not only they are heaver they require are a back mounted battery tethered to the gun itself. They also have much shorter range so only the best trained and coolest under pressure are issued Hotshot weaponry.
Auxilia lasrifle
Even during the great crusade, when the Imperium technology was arguably at his peak, the basic human foot soldier still defaulted to a form of lasrifle not too different from the 40k era one. The 30k lasrfile was equipped with various attachments but their usefulness was questionable at best. The Blast Charger is an odd piece of equipment that gives the user a single high strength shot but with no significant armor penetration at the cost of possible damage to the gun. The krak grenade being a simpler, more powerful and practical substitute. The collimator seems useful but the range extension is probably more than the average human soldier can exploit and ultimately need. As we learned in ww2, almost all small arms combat is fought inside 300 meters range. The comparison with the great crusade era is one of the best argument for the lasrifle being an ideal weapon in his role, despite technological availability and production issues
Volkite weapons
At the start of the great crusade, the Imperium used to field the powerful and terrifying Volkite guns. These technological marvels were almost completely phased out to the point that they are an extremely rare sight even a couple of centuries later during the Horus Heresy. While this is usually attributed to the Mechanicum inability to produce enough to equip the rapidly expanding Legion Astartes and Solar Auxilia, this does not explain how a weapon that numerous enough to be standard equipment and more powerful than its successor, mostly disappeared from the battlefield. Reason stands that they should have been kept in service for elite units. This means that either the Volkite weapons had some defects that made them less than ideal (that deflagrate ability doesn't seem so cool when the engagement comes to an uncomfortably close range and the range of the smaller versions is quite pitiful) or the weapons themselves were so delicate and maintenance intensive that they simply stopped working. Either way, if the Legions ditched them it seems unfeasible that the Imperial Guard could have adopted them en masse even if the Mechanicum could produce enough of them.
Skitarii Rad Carbines / Galvanic Rifles
Rad carbines are a very nice tool. Too bad they tend to kill the user by radiation poisoning, so no-no. Galvanic rifles are basically designated marksmen rifles and not clearly intended for general use.
Arc Rifles
Arc rifles are fantastic "balanced" weapons. High rate of fire, good armor penetration, great stopping power. The small problem here is that they also require a full backpack power supply. Again not a very practical weapon for the average soldier.
Tau Pulse Weapons
Ah, the cheesiest, shootiest army ever. Their weapons are bound to be really good, right? Well, pulse weapons suffer from reduced range or horribly long barrels. Magazine capacity is good, but not nearly as good as the lasgun. They have really great stopping power, but the armor penetration is no better in a galaxy when no one goes into battle unarmored better according to both fluff and pre-8th crunch (comparable to a non-primaris bolter) but doesn't fare much better against anything tougher than Flak armor. Recoil is also a thing, while not horrible as the one of a boltgun.
Las weapons and AA
The problem of hitting a flying object with a gun is that the flyer is moving at high speed in a three dimensional space. That means that to hit it with a "bullet" you need to know where the flyer be when the bullet will cover the relative distance between the shooter and the target. You need to detect the precise three dimensional position and velocity vectors. Then you have to factor the variable speed of the bullet and his ballistic trajectory. And even if you do all that with the near-perfect accuracy, the target might just change his velocity (maneuver) and dodge it.
That's why in modern warfare all AA, except at the very most close range, is handled to missiles instead of guns.
All this problems disappears if you have a practical las weapon that will fire a las beam at speed of light. Even if your target is - say - 300 kilometers away, the las beam will reach it in a millisecond. Flying at mach 3, the object would displace by only one meter in one millisecond and still be hit. This means that hitting a flyer with a las weapon would be extremely easy even without any dedicated equipment if close enough to be seen by naked eye. With radar auspex firing control you will basically hit flyers as soon as you detect it. The main strength of flyers (being harder to hit) will disappear and they will become the easier targets on the battlefield because they have no chance of cover and they cannot be as hard armored as something on the ground.
However, China and a few other countries (read: every first world country because no duh) have begun research into armor coatings designed to reflect or disperse laser-based weaponry (whereas countries like the US are doing that and increasing the power of their lasers in the knowledge that reflecting or dispersing lasers won't work at a certain level of energy), which would offset that advantage (though perhaps shooting the planes anyway could help guide missiles in the air to their targets and could damage or destroy electronics like targeting devices or cause missiles to detonate inside the target); it helps that the coatings would likely be much less expensive than the lasers themselves. Unfortunately, due to the effects of massed fire, such a coating would soon fail. Or, fire of a certain intensity, again and science says the laser simply won't be affected by such coatings at all...
Even if we invent coating that works perfectly well to protect aircraft, lasers could have a role in missile defence. After all, unless we can easily, and affordably, apply enough coating for every non-reusable explosive missile fired, the upsides of anti-air lasers could revolutionize missile defence.
Unfortunately this would clearly not work in 40k. In M2 some ablative/reflective coating might protect an airplane/missile because nowadays lasers are relatively weak and work by overheating and damaging delicate parts. An imperial lascannon does simply punch a clean hole through a Leman Russ battle tank with a big explosion of stuff rapidly heating to plasma. This will laugh at any "anti laser coating".