4 adjectives to describe firer

Also the Queen Mary mounted other big guns and rapid firers.

They must have set those anti-aircraft quick-firers of theirs in fresh elevated emplacements after the Yankees had taken the measure of their power to do harm; but the trap, if such it was intended to be, had failed to catch a single victim.

They must have set those anti-aircraft quick-firers of theirs in fresh elevated emplacements after the Yankees had taken the measure of their power to do harm; but the trap, if such it was intended to be, had failed to catch a single victim.

Dozens of light rapid-firers were dragged along by hand.

4 adjectives to describe  firer