Abstract: The chain gun simulator provides a high-fidelity simulation of the electrical control system signals for any weapon platform using a variety of chain gun types. The simulator device is stand-alone, requiring no external equipment, and replicates the electrical states, levels, and timing of the real guns such that the weapon platform's fire control interface can function normally without the need for a real gun and live ammunition. In addition, the simulator provides user control for selecting gun type and mode, and provides visual indication of modes, feed selection, and simulated weapon bolt position. There may also be an audible indication every time the simulator has advanced through the normal shutdown portion of the gun cycle.