This is a Full-Auto profile, AR-15 Complete Bolt Carrier Group that has been coated with a NiB-x/Nickel Boron coating. All of the components of the bolt carrier group are manufactured for WMD gun by Defense Industrial Base suppliers. The components are manufactured to WMD’s exacting standards in order to provide you with an AR-15 bolt carrier group of the highest quality.
Once formed from their raw materials, the components all go through a nickel boron treating process. This process is what separates the WMD bolt carriers from others on the market. This nickel boron, or NiB-X coating provides you with several advantages. This polished coating prevents fouling and other debris from sticking onto the surface. This allows the dirt and debris to flow out of our rifle, where it will not cause an issue. In addition to this, the NiB-X coating is said to increase reliability and also make cleaning and maintenance much easier. This can be particularly useful in short barrel rifle or suppressor set-ups.
The NiB-X coating has been thoroughly tested and was put through a government protocol endurance test that consisted of over 30,000 rounds. During that testing, WMD claims that the coating did not wear off.
The bolt that is included with this package has been machined from Carpenter 158 steel. The steel is heat-treated, shot peened, and magnetic particle inspected prior to assembly. This ensures that the bolt is stronger, more resistant to cracking and doesn’t have an non-visible defects.
The extractor used in this set-up is of mil-spec quality. It is manufactured, heat treated and hardened per military specifications
The included firing pin is also a mil-spec part.
The bolt carrier is machined from 8620 steel and is give a full-mass, M16 profile. This is slightly heavier than the semi-auto profile bolt carrier groups. The extra mass of the full-auto bolt carrier can increase reliability, as the carrier will have more momentum to plow though dirt and debris when going into battery during the firing cycle. Although the bolt carrier is a M16 profile, it is not considered a full-auto part and is not restricted from possession in any way. It is perfectly legal to own.
The gas key is affixed to the carrier with Grade 8 hardened fasteners to sure an attachment that will last through the recoil of firing. To further ensure a proper mating between the gas key and bolt carrier, Permatex Aviation Form-A-Gasket No 3 Sealant is used when mounting the gas key to the carrier. This is in accordance with MIL-STD-45180. As a final measure of security, the gas key is properly staked in place to mechanically block the screws from backing out.