CMC Triggers AR-15 Bolt Carrier Group 6mm ARC

Built around 6mm ARC compatibility, this AR-15 bolt carrier group keeps the familiar modular AR pattern while addressing a few spots that matter once the rifle gets dirty, suppressed, or short-barreled. The carrier uses a flared rear profile to reduce tilt and cant during recoil, and CMC shifts the bearing surfaces to cut down contact area and friction.

The carrier itself is case-hardened 8620 steel, while the bolt is a true mil-spec dimension 9310 case-hardened steel unit with CNC-ground external surfaces after heat treatment for a precise fit. CMC also machines the area behind the gas rings smooth after heat treat, which helps with carbon cleanup in a place that usually gets ugly fast. Added carrier mass is intended to support gas pressure and dwell time for extraction, especially in suppressed rifles and SBR setups.

Supporting parts stay in familiar AR territory: a hardened 4340 cam pin, mil-spec 8740 steel firing pin, and a mil-spec extractor spring with O-ring. The black nitride finish and enlarged forward ports round out the package.

Specifications

• Compatible with 6mm ARC
• AR-15 bolt carrier group
• Carrier material: case-hardened 8620 steel
• Bolt material: 9310 case-hardened steel
• Finish: Black Nitride
• Cam pin: hardened 4340
• Firing pin: mil-spec 8740 steel
• Extractor spring: mil-spec spring with O-ring
• Testing: MPI and HPT tested
• Color: Black
• MPN: 81635
• UPC: 810943031890