A simulated gun includes a main body and a reactionary force generator having a drive force generator, an actuator and a transmitter. The drive force generator is arranged outside the main body and transmits a drive force to a core constituting the transmitter by driving of the drive force generator. The rotational arm of the actuator is rotated together with a weight about the horizontal axis by a drive force from the core, and a drive force in a direction for raising the muzzle side of the gun is imparted to the main body when the weight hammers the inner wall surface of the main body. Consequently, a specified impact force can be generated by the drive force generator arranged outside of the main body, the size and weight of the main body can be reduced, and a realistic reaction force such that the muzzle side of the gun is sprung up can be realized.