Patent ID: 7600461

Claim:
A muzzle brake having a rear end, a front end and a central axis, the muzzle brake comprising: a plurality of axially spaced turning vanes including a rearmost turning vane; each of the plurality of axially spaced turning vanes having an inside diameter that is substantially equal to or greater than an inside diameter of the rearmost turning vane, at least one of the plurality of axially spaced turning vanes having an inside diameter that is greater than the inside diameter of the rearmost turning vane, none of the plurality of axially spaced turning vanes having an inside diameter that decreases in a direction from the rear end to the front end of the muzzle brake; each of the plurality of axially spaced turning vanes having a thickness that is substantially equal to or greater than a thickness of the rearmost turning vane; and a supersonic flow passage inside the muzzle brake wherein each turning vane is a supersonic turning vane comprising a suction side and a pressure side; the suction side including an expansion turning wall, the expansion turning wall comprising an angled portion and a substantially straight portion wherein the expansion turning wall creates an expansion fan that projects into the supersonic flow passage to turn supersonic flow into the turning vane; the pressure side comprising a pressure side curved surface, the pressure side and the suction side converging to form a throat wherein a shock is formed upstream of the throat, the shock decelerating the supersonic flow to subsonic conditions and the pressure side turning the subsonic flow; the suction side including an outer nozzle expansion wall downstream of the throat, the outer nozzle expansion wall diverging from the pressure side to form an expansion nozzle that expands the subsonic flow to supersonic conditions.