AO Precision Enhanced Phosphate Bolt Carrier Group – 158 HPT/MPI

Description

AO PRECISION ENHANCED MIL-SPEC PHOSPHATE BOLT CARRIER GROUP – 158 HPT/MPI BCGThese Military surplus 158 Bolt carrier groups are manufactured by AO Precision to the exacting standards of the US Military. AO makes these HPT / MPI BCG’s for other Military contractor juggernauts, such as FN America. All bolts are rigorously inspected and are individually High Pressure Tested and then go through a Magnetic Particle Inspection. All springs have been replaced with Sprinco springs, specifically their 5 coil extractor spring and enhanced ejector spring.
Mil Spec Bolt

158 Carpenter Steel
Shot Peened
High Pressure Tested (HPT)
Magnetic Particle Inspected (MPI)
Sprinco Enhanced Ejector Spring
Made from Chrome Silicon wire stock
Heat treated, stress relieved, and cryogenically processed
Much longer service life than OEM
Improves reliability
Mil Spec Carrier

8620 Aircraft Grade Steel
Full Mass M-16

Mil Spec Extractor

4140 Steel per ASTM A108, cold drawn and stress relieved BHN 187-22
Phosphate Finish
Sprinco 5 Coil Extractor Spring
5 coil design
For AR-15 BCG
Made from Chrome Silicon wire stock
Heat treated, stress relieved, and cryogenically processed
Mil Spec Gas Key

4130 Profile Extruded Steel
Grade 8 Hardware
Properly Staked
Chrome Lined Interior

Please note: These BCG’s are made to order and may take 5 to 7 days to ship.