Black Nitrided AR15 5.56/.300BLKOUT M16 Bolt Carrier Group Features; Shot peened, MPI (Magnetic Particle Inspected), 9310 Tool Steel Bolt; 8620 M16 carrier, Properly staked 4140 Machined Gas Key fastened with Hardened Grade 8 Fasteners. Extractor includes crane o-ring. The requirements for assembly of our Bolt Carrier Groups are much higher than most. Before assembling the gas key to the carrier, permatex NO.3D aviation is applied to form-a-gasket around the gas hole (per MIL-SPEC). Then Grade-8 hardware is used to attach the gas key, followed by properly staking per spec. When installing the extractor to the bolt, a crane-o-ring is inserted with the spring to insure proper ejection. Then high temperature grease is applied to the gas rings before inserting the bolt into the carrier, which allows for much smoother operation. These BCGs are inspected to the highest of standards, to insure a high quality product that is 100% reliable for our customer… PROUDLY MADE IN THE USA!
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