US Patent 11231248 Recoil assembly for a machine gun

A recoil assembly for a rifle includes a barrel assembly, a bolt, bolt actuator, and a buffer assembly. The barrel assembly includes a barrel secured to a barrel extension. The barrel assembly is configured to be movably received through the fore end of the upper receiver and to move axially relative to the upper receiver when the rifle is fired. The barrel extension is coupled to a hydraulic buffer assembly located below the barrel extension and counteracts recoil forces acting on the barrel extension when the rifle is fired. An op-rod spring is coupled to an op rod extending from a gas piston assembly on the barrel. The op-rod spring counteracts recoil forces acting the bolt actuator when the rifle is fired.