JP LMOS Low Mass Bolt Carrier Group

Complete JPBC-3 Bolt Carrier Assembly with Low Mass Carrier and .223 JP EnhancedBolt™ with cam pin, firing pin and firing pin retainer.

For the no-compromise competition rifle, JP's Low Mass Operating System (LMOS™) offers the most significant improvement in the felt impulse of the rifle compared to any modification other than the addition of a compensator. By reducing the reciprocating mass within the operating system, the bolt velocity is increased while simultaneously reducing the overall impulse experienced by the shooter with each shot. Consequently, LMOS™ equipped rifles have virtually no reciprocating mass feel and move less during cycling, allowing for much faster sight recovery and follow-up shots.

While use of the LMOS™ components is recommended only for competition and sporting use, this is only precautionary as their reliability is excellent, particularly on rifles with adjustable gas systems. Like all our bolt carrier designs, LMOS™ carriers feature a 100% increase in bearing surface for smoother operation, improved alignment and lower wear in the upper receiver as well as the longer Mil-spec. cocking pad for optimal reliability. In fact, Team JP shooters have been using the LMOS™ system for over a decade without any reported operating system malfunctions at a match, and most every shooter that implements this operating system feel that it is proven to be a great performance improvement. Some shooters have even reported fewer unexplained flyers in their groups after switching to the LMOS™ system.

For small-frame rifles, the complete JP LMOS™ system consists of one of JP's low mass bolt carriers and JP's lightweight buffer conversion kit, but any LMOS™ component can be installed individually in your existing setup and run smoothly.