Sons of Liberty Gun Works SOLGW Hard Chrome Bolt Carrier Group - Carpenter 158 Bolt

Sons of Liberty Gun Works Bolt Carrier Group is a premium BCG that leaves no stone unturned when it comes to quality control and performance.

Bolt:

Precision machined from Carpenter Technology No. 158 chrome-nickel alloy
Heat treated per mil-spec,
Shot peened per ASTM B851/SAE AMS2430S,
Vibratory tumbled
Individual high pressure/proof (HP) test
Full Auto test fired at assembly
Individual magnetic particle inspection ASTM E1444/E1444M (MP)
Markings deep laser engraved (SP=Shot Peened, HP=High Pressure Tested, MP=Magnetic Particle Inspection.)

Extractor:

Precision machined from 4340 tool steel alloy per SAE AMS6415T/AMS6484D (vs 4140)
Heat treated
Shot peen per ASTM B851/SAE AMS2430S

Extractor Retaining Pin:

Precision machined and ground S7 Tool Steel
Heat treated per ASTM A681-08
Shot peened per mil-spec print

Extractor Spring:

Tactical Springs/Sprinco 5 coil, ASTM Grade A401 Chrome Silicon wire stock
Heat treated
Stress relieved, Molybdenum-Disulfide infused
Cryogenic processed (Hidden post winding)
Mil-spec black insert/synthetic elastomer extractor buffer (nitrile-butadiene, shore hardness 80+/-5 durometer per MIL-PRF-6855)

Ejector:

S7 Tool Steel
Heat treated per ASTM A681-08
Shot peened per Mil-Spec
Ejector Spring:
Heat treated
Mil Spec

Gas Rings:

Standard stainless steel per Mil-Spec X3

Carrier:

Machined from AISI 8620 aircraft quality alloy per ASTM A108/A322-13
Full auto profile
Heat-treated
Carburized/strain relieved, hard chrome bore
Precision ground gas key interface
Sons of Liberty Battle Flag logo deep laser engraved

Gas Key:

Machined from 4130 Chromoly steel alloy per ASTM A108/A322-13
Heat-treated; hard chrome internal
Permatex sealed
Grade 8 hex screws torqued and staked Hidden per mil-spec

Cam Pin:

Precision machined 4340 Chromoly steel alloy per SAE AMS6415T/AMS6484D
Heat-treated/processed per mil-spec
Solid film lubricant applied and cured per mil-spec

Firing Pin:

Precision machined 8640 steel alloy
Heat treated/processed per mil-spec
Hard chrome plate

Firing Pin Retaining Pin:

Precision machined from 1038 carbon steel
Heat-treated/processed per mil-spec