Easy-to-install kit lets you convert an AR-15 carbine to a smooth-running short-stroke gas piston operating system for cooler, cleaner, more reliable operation, positive cycling, easy maintenance, and the freedom to fire a wider variety of ammunition. The kit contains all the parts to convert the standard gas impingement system to the rugged, reliable op system employed so successfully in the Kalashnikov AK series, FAL, HK416, FN SCAR, and other tactical rifles. Eliminates the risk of broken gas rings, sagging gas tubes, and the accelerated wear caused by venting hot gas, debris, and carbon fouling inside the upper receiver. Bushmaster has extensively torture-tested this system, ending with a 10,000-round non-stop endurance test without a single failure. Hot gases are vented under the kit’s handguard, away from the operator, so only the energy required to cycle the action is transmitted to the receiver. Stainless steel shielding inside handguard protects your hand from the heat buildup of sustained fire. Kit includes a high-performance replacement bolt carrier with extra mass, an integral impact lug, and other anti-wear features to protect receiver from the impact of the piston. The lightweight, low-maintenance stainless steel piston is housed in a tubular structure that replaces the existing gas tube and pins directly to your rifle’s factory front sight tower—no need to install a new sight system. Installs in any mil-spec, factory upper without permanent modifications; any time you want to return your rifle to its factory gas system, simply swap out the piston system and replace the original parts.
SPECS: Steel, Parkerized, matte black. Handguard – Molded polymer, black, stainless steel heat shields. Kit contains bolt carrier, piston rod, spring, piston housing, piston housing support, M4-style handguard, and installation instructions. Fits semi-auto rifle with M4 profile carbine-length barrel that has .875” O.D. behind front sight housing.
Catalog page 453