Shotgun
The Shotgun is a pump-action weapon utilised by the Imperium of Man. It is a short-ranged anti-personnel weapon, and easily fired accurately on the move thanks to it's wide spread of fire.
It is commonly employed by Space Marine Scouts and Imperial Guard Veterans, although the Space Marines are equipped with more powerful "Manstopper" rounds. It's hail of shot can shred through flesh, but it's low velocity causes it to be ineffective against armoured enemies.