Midwest Industries 5.56/AR-15 Black Nitride BCG

The Midwest Industries Black Nitride Bolt Carrier Group delivers reliable cycling and extraction for AR-15 pattern rifles chambered in 5.56 NATO/.223 Remington. This BCG replaces factory or worn bolt carrier groups, offering improved corrosion resistance and reduced friction compared to phosphate-coated carriers. Shooters upgrade to this BCG for easier cleaning, smoother operation, and extended service life in high-volume shooting environments.

Machined from 8620 steel with a black nitride finish inside and out, this bolt carrier group runs cleaner and cooler than traditional coatings. The nitride treatment penetrates the steel surface rather than coating it, providing permanent hardness and lubricity. This is a drop-in replacement for mil-spec AR-15 lower receivers—no fitting or modification required. Includes gas key properly staked per military specifications, extractor with O-ring and spring, and ejector assembly.

• Part Type: Bolt Carrier Group
• Compatible Firearms: AR-15, M16, M4 (5.56 NATO/.223 Remington)
• Material: 8620 Steel
• Finish: Black Nitride
• Installation: Drop-In
• Includes: Bolt, Carrier, Gas Key (Staked), Cam Pin, Firing Pin, Retaining Pin, Extractor Assembly, Ejector Assembly