Fostech Complete Bolt Carrier Group Black

The Fostech Complete Bolt Carrier Group Black is a precision-engineered, full-auto profile M16-cut assembly designed to function with the Echo AR-II and Echo Sport platforms. Built to mil-spec standards with premium materials, this bolt carrier group delivers the reliability required for sustained operational use across multiple caliber platforms including .223 Remington, 5.56 NATO, and .300 Blackout ammunition.

The bolt assembly features 9310 alloy steel construction with shot-peened hardening and magnetic particle inspection, ensuring dimensional consistency and fatigue resistance under high-round-count use. The hardened tool steel extractor is paired with a Viton mil-spec O-ring for reliable case extraction across pressure curves and environmental conditions. Three mil-spec gas rings maintain optimal bolt-to-carrier gap while reducing carbon fouling. Black Nitride finish provides corrosion resistance and reduced friction without the wear signature of bare steel.

This bolt carrier group is purpose-built for users of the Echo AR-II and Echo Sport platforms who require a drop-in replacement or upgrade component for extended service life. The multi-caliber compatibility (.223, 5.56, .300 BLK) suits shooters who run multiple load configurations within the same upper receiver, eliminating the need for separate carrier assemblies. Appropriate for law enforcement transition training, tactical rifle maintenance, or civilian precision shooting where carrier reliability directly impacts system consistency.

M16-cut carriers are the industry standard for direct impingement systems and feature full-auto geometry, meaning semi-auto platforms benefit from a heavier, more controllable cycle. The premium material grades and Fostech manufacturing standards position this carrier above standard mil-spec minimum, supporting higher round counts and more consistent velocity node maintenance when paired with matched bolts and quality ammunition.