This work (a continuation of the author’s prior research on small arms recoil reduction) presents a rifle operating
group design for small arms recoil reduction. This recently-patented invention is an application of a previouslypatented
7.62mm concept demonstrator to reduce the recoil force transmitted to the user during operation. The recoilmitigating
technology developed for the original 7.62mm concept demonstrator has been packaged into a compact and
practical rifle operating group design. Like its predecessor, the rifle operating group (the rifle internal components that are
responsible for ammunition feeding, firing extracting and ejecting) includes design features to reduce the propellant gas
contribution to recoil force and cancel the moving internal component contribution to recoil force. The specific design
features in the original invention and follow-on invention for recoil reduction are a translating barrel, a spring-supported
upper receiver and a counter-mass that is driven by rack and pinion gears. In computer-based firing simulations, the rifle
operating (like its predecessor) produced recoil reaction forces that were substantially less than those produced by the
M240 machine gun.
Gun, inertia, mechanism, momentum, recoil reduction, small arms.
Department of Mechanical and Industrial Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102-1982, USA.