US Patent 11629927 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 a 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.