TacFire AR-10/DPMS Bolt Carrier Group Features The TacFire Bolt Carrier Group pairs an 8620 steel carrier body with a 9310 steel bolt a material combination widely used in higher pressure AR-10 pattern rifles because of its superior strength and fatigue resistance compared to lower grade alloys. Every carrier group receives a QPQ nitride treatment a finish that hardens the surface reduces friction during cycling and resists corrosion far better than a simple phosphate coating. Each unit is magnetic particle inspected before it leaves the factory a quality control step that catches subsurface flaws a visual inspection alone would miss. The carrier is also shot peened a process that relieves surface stress and extends fatigue life under the repeated cycling of a semi-automatic action. Built specifically to the DPMS profile the carrier group is designed to drop into AR-10 pattern rifles using that bolt and carrier footprint without fitting work. The carrier is serrated to work properly with a forward assist ensuring the feature functions as intended on rifles equipped with one. A nitride treated gas key staked according to mil-spec practice keeps the key from loosening under the gas pressure generated by repeated firing. For an AR-10 or DPMS pattern rifle owner needing a durable replacement or spare bolt carrier group the TacFire Bolt Carrier Group in .308 Win is available for sale at GrabAGun. TacFire AR-10/DPMS Bolt Carrier Group Specifications Manufacturer: TacFire Model: Bolt Carrier Group Caliber: .308 Win Compatible Hosts: AR-10 DPMS Color: Black Material: Steel Finish: Nitride Available At: GrabAGun