Rosco Manufacturing Bolt Carrier Group .300 AAC Blackout/5.56x45mm, Black

Rosco's 5.56x45mm and .300 AAC Blackout Bolt Carrier Groups are engineered for durability, reliability, and peak performance. These full-auto-rated BCGs feature a Melonite coating that enhances wear resistance and corrosion protection, ensuring long-term functionality under harsh conditions. Each unit is built to MIL-SPEC standards, with a properly staked gas key for secure operation and a matched bolt that undergoes shot peening and magnetic particle testing for superior strength. Designed to l