Abstract

This work presents a recently-patented mechanical buffer design to reduce bolt carrier bounce in the M4 and M16 rifles. The buffer includes a main outer spring to store the energy in a rearward-traveling bolt carrier and a nested spring coupled to a mass to counter the rebound or “bounce” resulting in the impact of a forward-traveling bolt carrier. A dynamic model of the mechanical buffer is included to demonstrate bolt bounce and the mechanical buffer concept.

Keywords: Mechanical buffer, bolt bounce, spring-mass system, M4 carbine, M16 rifle