The Enhanced bolt carrier is machined from heat-treated 8620 steel and features an S7 gas key, along with secured M16 screws that are staked using 3,500 foot-pounds of force, ensuring that the gas key won't loosen, even under heavy use.
The bolt itself is constructed from C158 steel and features a black-nitride finish for added durability. The company grinds the bolt between centers in order to ensure perfect concentricity. The extractor is made using tool steel, and the firing pin is constructed from stainless steel in order to resist corrosion and excess wear. The bolt also features a mil-spec O-ring.
The firing pin retaining pin is also finished in a black-nitride treatment and is constructed using the M67 firing pin retaining pin. The M67 pin is based on the original Eugene Stoner BCG design and was used in all AR-10 and AR-15 rifles until it was replaced by a standard cotter pin in 1967 in order to cut costs. The original M67 pin performs a better job at retaining the firing pin than the replacement cotter pins, so it is included in order to provide premium performance.
The bolt-carrier groups sold by Leitner-Wise are shot-peened and are high-pressure proof fired and X-rayed in order to ensure steel quality, performance and reliability. In addition to the Enhanced Bolt Carrier Group, the company also sells carriers only, including the staked gas key and nothing else.
The usual suggested retail price on the Leitner-Wise 5.56 Enhanced Bolt Carrier Group is $165, but for a limited time, the company is offering the BCGs for a sale price of $145.