Battle Arms Development M4/M16 Standard BCG – AR-15/M16 Bolt Carrier Group

The Battle Arms Development M4/M16 Standard BCG is a mil-spec bolt carrier group designed for reliable cycling in AR-15 and M16 platform rifles. This is a direct replacement for factory bolt carrier groups, delivering consistent performance for range work, training, and duty applications. Machined to correct specifications, it provides the proper headspace and cam pin timing required for safe, dependable function.

The carrier is machined from 8620 steel and properly staked, while the bolt is made from 9310 steel and shot-peened for enhanced fatigue resistance. The assembly features a phosphate finish for corrosion resistance and proper lubricity. This is a drop-in part for shooters maintaining existing rifles or building new uppers. Standard maintenance and lubrication intervals apply.

• Part Type: Bolt Carrier Group
• Compatible Firearms: AR-15, M16, M4
• Carrier Material: 8620 Steel
• Bolt Material: 9310 Steel, Shot-Peened
• Finish: Phosphate
• Installation: Drop-In
• Includes: Bolt, Carrier, Cam Pin, Firing Pin, Firing Pin Retaining Pin