Rosco Manufacturing Bolt Carrier Group for AR-15 – 5.56 NATO/.300 Blackout, Phosphate Finish (ROS-BCG-002)

• Bolt carrier group for AR-15 platforms supporting 556NATO and 300 Blackout chamberings
• 8620 steel carrier with phosphate coating and chrome lined gas key and bolt channel
• C158 bolt material phosphate coated and MPI HPT tested for durability and consistent cycling performance
• 4130 steel gas key properly staked and secured with Grade 8 hardware for reliability
• Includes Sprinco upgraded extractor kit with heat treated 4140 extractor and shot peened components
• Full auto rated assembly engineered for repeated firing cycles and demanding field conditions

The Rosco Manufacturing Bolt Carrier Group 556NATO/300 Blackout AR-15 Phosphate Chrome Lined Black is a bolt carrier group designed for cycling and operation in AR-15 platforms. This bolt carrier group supports 5.56 NATO and 300 Blackout calibers and features a phosphate exterior with chrome lined internal channels.

The Rosco Manufacturing bolt carrier group includes an 8620 steel carrier and a C158 bolt that is MPI and HPT tested with a phosphate coating. It uses a 4130 steel gas key with proper staking and Grade 8 hardware, along with a hardened 4340 cam pin and chrome plated 8740 firing pin. The extractor is 4140 steel and includes an upgraded Sprinco kit, while the ejector uses tool steel construction. This model is used for rifle builds and maintenance in AR-15 systems requiring chrome lined and mil-spec components.