Tweet   Atchisson Assault Shotgun, or AA-12. Fully automatic and drum-fed, the AA-12 fires five 12-gauge shotgun shells per second, with extreme reliability and so little recoil that strong men can shoot it Arnie-style with one hand. And if that hail of hot buckshot isn’t enough to make both shooter and target need a change of underpants, consider this: it has been developed in conjunction with the FRAG-1 More..2 - a new type of shotgun cartridge in which each round is a small, flighted high explosive or fragmentation grenade accurate up to 175 metres.