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CMMG
Overview
The CMMG Barrel Sub-assembly is a 16-inch barrel specifically designed for 9mm builds that utilize a blowback gas system. Its QPQ/Nitride coating provides enhanced durability and corrosion resistance, making it suitable for continuous use. This barrel is compatible only with the RDB BCG, ensuring a tight fit and optimal performance in your 9mm AR-15 configurations, often seen in PCC (Pistol Caliber Carbine) builds.
Specifications
CMMG Barrel Sub-assm 16 Mt 4140CM SBN 9mm Only Compatible With Rdb BCG
Price and stock
Availability is good for the CMMG Barrel Sub-assm 16 Mt 4140CM SBN 9mm Only Compatible With Rdb BCG: it was in stock at one retailer or another nearly every day in September 2026, and today only CMMG has it in stock. Prices barely moved in September 2026, holding around $324.95, so there haven't been real sales lately. Buying today, the lowest price is $324.95 at CMMG, which matches the best price we saw in September.
Prices checked · refreshed daily across 37 retailers
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