The Spike's Tactical HPT/MPI M16 Bolt Carrier Group for 223 Remington/5.56 NATO features a Mil-Spec 8620 tool steel M16 bolt carrier w/shrouded firing pin. The carrier has 126.96.36.199 MIL-STD-171 phosphate finish inside and out with 188.8.131.52 MIL-STD-171 hard chrome bore. It is laser-engraved with ST Spider logo which is visable through ejection port door opening. The carrier key is attached with Grade 8 hardware and properly staked per the Mil-Spec. The bolts are CNC machined from Carpenter No. 158 and have 184.108.40.206 MIL-STD-171 phosphate finish inside and out. All bolts are shot peened per the current Mil-Spec and individually High Pressure Tested (HPT) and then Individually Magnetic Particle Inspected (MPI). The tool steel extractor is shot peened, has a 220.127.116.11 MIL-STD-171 phosphate finish, and is fitted with a Mil-Spec black extractor spring insert and Mil-Spec Viton o-ring. The Mil-Spec firing pin has a 18.104.22.168 MIL-STD-171 hard chrome finish. The Mil-Spec cam pin also has a 22.214.171.124 MIL-STD-171 phosphate finish. The Mil-Spec firing pin retaining pin has a 126.96.36.199 MIL-STD-171 phosphate finish.
|Size||223 Remington/5.56 NATO|
|Type||Bolt Carrier Group|
|Series||HPT/MPI 223 Rem/5.56|
Determined at checkout.