A*B Arms Pro 5.56 NATO Bolt Carrier Group Nickel Boron

A*B Arms Pro 5.56 NATO Bolt Carrier Group - Nickel Boron A*B Arms is built stronger because sometimes, lives are on the line. Their products stand up to the rigors of combat, police and private security operations, where failure is not an option. The A*B Pro 5.56 Bolt Carrier Group is a MIL-SPEC drop-in ready component for the AR-15/M4 platform. The nickel boron finish offers dry lubrication for treated parts. The carrier, bolt, and cam pin require virtually no lube during use. The phosphate coated extractor has a surface finish providing superior extraction during firing. Crafted using high-end Swiss machinery for tight tolerances and finish. Features: Bolt Carpenter 158 steel Heat treated Shot peened Magnetic particle tested Nickel boron coated Bolt carrier 8620 steel Nickel boron coated Nickel boron coated bore M16 cut Gas key 4130 steel Nickel boron coated Properly staked 4140 steel gas key screws Cam pin 4340 steel Heat treated Nickel boron coated Extractor Aircraft quality E4140 steel Heat treated Shot peened Manganese phosphate coated Firing pin AISI 8740 steel Chrome coated