ROSCO 556NATO/300BLK BCG MELONITE BK

ROSCO 556NATO/300BLK BCG MELONITE BK – TOUGH, RELIABLE, BUILT TO RUN CLEAN

The ROSCO 556NATO/300BLK BCG MELONITE BK is a premium bolt carrier group built for dependability and low-maintenance performance. Coated in a sleek black Melonite finish, this BCG is engineered to withstand harsh conditions while running smoother and cleaner than traditional phosphate-coated carriers.

DESIGNED FOR 5.56 NATO AND .300 BLACKOUT

Optimized for both 5.56 NATO and .300 BLK, this bolt carrier group is an ideal choice for multi-caliber AR-15 setups. Whether you’re shooting suppressed or unsuppressed, supersonic or subsonic, the ROSCO MELONITE BK BCG delivers consistent, reliable performance.

MELONITE TREATMENT FOR LONG-LASTING DURABILITY

The Melonite (nitride) finish offers superior corrosion resistance, extreme surface hardness, and reduced carbon fouling. It penetrates the metal rather than just coating it, resulting in a longer lifespan and easier cleaning compared to traditional finishes.

MIL-SPEC CONSTRUCTION WITH MPI-TESTED BOLT

The carrier is machined from 8620 steel with a full-auto profile, and the bolt is made from 9310 steel—MPI-tested and shot-peened for maximum strength and durability. Each component is heat-treated and assembled to exacting MIL-SPEC standards.

DROP-IN READY FOR ANY MIL-SPEC AR-15

The ROSCO 556/300BLK BCG MELONITE BK comes fully assembled with a properly staked gas key, firing pin, cam pin, and retaining pin. It’s drop-in ready for any MIL-SPEC AR-15 upper receiver and designed to handle thousands of rounds with minimal maintenance.

FEATURES:

• Complete BCG for 5.56 NATO / .300 Blackout
• Black Melonite (nitride) finish for superior wear and corrosion resistance
• 8620 steel full-auto carrier
• 9310 MPI-tested bolt, shot-peened for added strength
• Properly staked gas key
• Fully assembled and drop-in ready

WHY CHOOSE THE ROSCO 556NATO/300BLK BCG MELONITE BK?

Rosco Manufacturing is trusted by professionals and builders for dependable, field-proven components. The ROSCO 556NATO/300BLK BCG MELONITE BK delivers top-tier durability, smoother operation, and compatibility across calibers—making it a smart upgrade for serious shooters.

ORDER YOUR ROSCO 556NATO/300BLK BCG MELONITE BK TODAY

Upgrade your AR with a bolt carrier group built to perform under pressure. The ROSCO MELONITE BK BCG gives you lasting reliability, cleaner operation, and cross-caliber versatility right out of the box.