Rosco Manufacturing Bolt Carrier Group, 556NATO/300 Blackout, Fits AR-15, Phosphate and Chrome lined Finish, Black ROS-BCG-002

These 5.56 / 300 BLK Bolt Carrier Groups are Phosphate Coated with Chrome Lined Gas Key & Bolt Channel, Full-Auto rated, properly staked, and the bolts are Matched to the barrel. The Nitride version features a melonite coating for extended performance. The Rosco Phosphate and Nitride Bolt Carrier Groups are designed to meet the modern-day carbine shooters requirements. They have also balanced input from their consumers and military end users in order to bring you the product you need, not just the one Rosco wants to sell you. All Rosco BCG’s are to MIL Specification and have a properly staked gas key along with a chrome lined coating for extended performance. They also feature a Shot Peened/ MP tested Matched bolt (with upgraded extractor) which is designed to lock up perfectly with their extensions for extreme accuracy. These BCG’s are made to withstand Full-Auto rated fire and unforgiving use from the end user. Carrier Material: 8620 Steel Gas Key: 4130 Steel, attached with Grade 8 hardware, properly staked Cam Pin: Hardened 4340 Steel Firing Pin: 8740 Steel, Heat Treated, Mil-Spec, Center-less ground, Hard Chrome Plated Bolt Material: C158, , Phosphate Coated, MPI/HPT Phosphate Extractor: 4140 Steel, Heat Treated, Shot Peened Nitride Extractor: 4340 Steel Phosphate Ejector: S2-S7 Tool Steel, Shot Peened Nitride Ejector: S7 Tool Steel Rosco Phosphate/Chrome ONLY BCGs ship with upgraded Sprinco Extractor Kit