LANTAC Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group Nitride Black. 223/5.56 Caliber. This bolt carrier group will not work in standard AR-15 upper receivers. It must be used with a side charging upper receiver. For guaranteed fit LANTAC recommends their LA-N15 Raven Side Charging Billet Upper Receiver. M16 Full Auto Style for increased mass and lock time. LANTAC BCG is precision machined from 8620 Steel with a shot peened bolt manufactured from Carpenter 158 or 9310 and Magnetically Particle Inspected. The entire carrier assembly is QPQ Nitrided for enhanced corrosion and wear resistance. The carriers patented design features unique shrouded and forward facing gas ports that have also been re sized so that gas is vented differently to a standard carrier. This results in a system that runs flatter with a smoother energy pulse. In addition the system also runs cooler and cleaner there is also less pressurization of the upper receiver when running a suppressed barrel. The flared boss at the tail of the carrier enhances the BCG's lock position within the upper and makes it more consistent resulting in an accuracy improvement. All critical dimensions are hard turned / ground after heat treat and the gas key has been hard chrome lined for the best possible wear resistance. All E-BCG's feature the LANTAC CP-R360 patent pending domed head cam pin that is machined from 17-4PH Stainless Steel and hardened to H900 condition (45RC approx). The ultra smooth head reduces wear within the upper receiver. The BCG's 11.7oz weight (Excluding Handle) helps to increase lock time and smoother operation. Gas keys are properly staked at four points and only grade 8 fasteners are used in assembly. The E-BCG's forward porting and unique shape assist in reducing pressurization inside the upper receiver that can be caused by short barrel rifles running suppressors. However it should be noted that the E-BCG is not a complete solution for this issue and all rifles are different. Over Gassed guns will suffer to a larger extent from this problem. Specifications for LANTAC Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group: Manufacturer: LANTAC Finish: Nitride Fabric/Material: 8620 Steel Caliber: 5.56x45mm NATO .223 Remington Gun Make: AR Platform Gun Model: AR-15 Weight: 11.7 oz Condition: New Features of LANTAC Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group Forward Porting enlarged vents Balanced flared boss 8620 Carrier Heat Treated Hard Turned and Ground. MPI Carpenter 158 or 9310 Bolt Shot Peened Hard Turned / Ground CP-R360 Domed Cam Pin Mil-Spec Gas Rings Mil-Spec Staked Gas Key Grade 8 Hardened Fasteners All Hard Chrome surfaces are to MIL-STD-171 1.2.2.2 Shot Peening is conducted with S110 shot Established by Almen Gage A-2 strip .006 -.008 Lifetime Warranty Package Contents: LANTAC Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group 440 Stainless Steel Knurled screw in handle What firearm models does the manufacturer say LANTAC Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group is compatible with? The manufacturer says that LANTAC Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group is compatible with AR-15LANTAC 01-UP-SC-NIT-EBCG: Enhanced DI Side Charger AR-15 .223 Remington/5.56x45mm NATO Bolt Carrier Group Nitride Black