automatic rifles work by the exerting gas made from the bullet and the gas pushes back the bolt loading a new round in
Gas or recoil operates the action.
the gas pressure from the exploding shell ejects the empty casing and activates the reload mecanism
Yes
Yes
Embellishment
Yes
Yes
Generally Yes.
Browning Automatic Rilfe
Semi automatic
Fully automatic shotgun, no. Automatic rifles and machine guns, yes.
Just fine.