• Full Mass Operating System (FMOS)
• Over-sized carrier bearing surfaces
• Bolt is finished in Chromium Nitride 
• 9310 EnhancedBolt
• Additional material around cam pin hole
• Enhanced one piece gas ring
• Melonite QPQ (Quench Polish Quench) finish
• Complete with cam pin, firing pin & retainer pin
• Compatible with DPMS patterned bolts, firing pins & cam pins

Weight: 1lb. 2.7 oz.

The JPBC-5A is a premium complete bolt carrier group for the DPMS patterned large frame rifles. The Full Mass Operating System provides for the maximum reliability possible. The enlarged bearing surfaces can increase reliability, and make for a very smooth impulse. The JP EnhancedBolt is made from SAE 9310 tool steel. This material makes for an extremely hard surface with a tough, ductile core resistant to structural failure and a life expectancy far exceeding Mil-spec 8620-type bolts. SAE 9310 is the same type of steel used in the transmission gears of Formula One race-cars, and the high-load application of a bolt assembly is ideal for this state-of-the-art material; the results of actual full-auto endurance torture tests prove it.

The LMOS is compatible with both DPMS and Armalite, but you should never mix the two types of parts when not buying a complete BCG.

For more info, visit JP Enterprises