A weapon training device include a frame, a reciprocating member in sliding longitudinal engagement with the frame, and a magazine coupled to the frame. The magazine has a compressed gas chamber in fluid communication with a valve. A light emitter actuated by a switch tied to a trigger is disposed in a barrel. A fire control module has a trigger that is releasably engaged thereto and positioned in axial alignment with the valve, and linked to the switch. A piston is fixed to the frame and is in fluid communication with the magazine valve. A piston sleeve is fixed to the reciprocating member, and the piston is be received therein. An impulse to the piston sleeve from the gas directed into the piston is transferred to a rearward longitudinal motion of the reciprocating member relative to the frame.