Abstract: The invention consists of four components: a diverter assembly, a blocking plate assembly, a blast deflector and an exhaust duct. The diverter attaches to the gun barrel clamp and rotates and recoils with the gun; as gases leave the gun barrels and enter the diverter they are redirected by it from axial flow to radial and tangential flow, thereby imparting a forward force and a torque to the barrel cluster. The blocking plate assembly does not rotate within the diverter and acts to limit the egress gas and the gas that flows into the non-firing gun barrels. The blast deflector has a collector that surrounds the diverter and collects the diverted gases. The duct receives the collected gases and conducts them to the desired exhaust ports.