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Modern Armory - Dickbutt Nitride C158 BCG

Modern Armory

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The MA Bolt Carrier Group - Auto Version - for your M4 or AR15.
  • 8620 Alloy Steel Carrier
  • H&M Nitride Finish
  • Blank or Logo Laser Engraved
  • Carpenter 158 Steel Bolt
  • Heat Treated
  • Shot Peened
  • MPI Bolt - Magnetic Particle Inspected
  • 4140 Phosphate Extractor (NON MIM)
  • 8620 Nitride Gas Key (Hand Lapped)
  • Gas Key Properly Installed Using Vibra-Tite 541
  • 8640 Steel Nitrided Firing Pin 
  • 8620 Cam Pin with directional arrow lasered on
  • Bolt Comes Pre-Lubed with our house blended lube
  • OCKS Fasteners
  • Sprinco 5-coil Extractor Spring
  • Sprinco Ejector Spring
The warranty is NOT transferrable and is only valid to the original purchaser.
Each BCG is individually test fired (3rds of ARMSCOR 223REM 55GR) BCG will ship as is, BCG was lubed and might be dirty from the test firing procedure.
The MA Defense Bolt Carrier Group is proudly MADE IN THE USA by hard working American men and women.
*Lifetime Guarantee covers manufacturing defects in materials and workmanship, regardless of the age of the product, but it does not cover normal wear and tear. Wear and tear is damage that naturally and inevitably occurs as a result of normal use.
ITAR: International Traffic in Arms Regulations Controlled