PSA 5.56 NITRIDE MPI FULL-AUTO BOLT CARRIER GROUP
Bolt Finish: Nitride
Bolt Steel: 9310
Profile: Full Auto Profile
Gas Key: Grade 8 Hardened Fasteners, Staked per MilSpec
Bolt is Magnetic Particle Inspected (MPI)
8620 Full-auto profile bolt carrier group with 9310 steel bolt. Gas Key Hardened to USGI Specifications, Fastened with Grade 8 screws, and Staked Per Mil-Specs.