NBS AR-15 9310 Bolt Assembly - Black Nitride - 6290

Made from 9310 Steel which has a high core hardness and high fatigue strength unlike standard Hot/cold rolled 9310 steels. This is a Mil-Spec bolt assembly with enhanced features for those looking to complete a bolt carrier group. This bolt will make sure your gun outshines the competition

– Fully Assembled 5.56/.223 Caliber Bolt

– Shot Peened

– MPI (Magnetic Particle Inspected)

– HPT (High Pressure Tested)

– Power Spring Kit

– Nitride QPQ Treated

– Engraved with MPI/9310