Diamondback DB Barrel 5.56x45mm NATO 5.50" 1:8 Pistol-Length Black Nitride

The Diamondback DB Barrel is a factory OEM replacement barrel designed for the Diamondback DB15 platform and other AR-15-pattern builds. Chambered in 5.56x45mm NATO with a compact 5.50" barrel, this replacement component is built around a heavy-profile pistol-length gas system.

Constructed from 4150 chrome moly vanadium steel and finished with a black nitride treatment for enhanced wear resistance and corrosion protection, the barrel features a 1:8 twist rate that reliably stabilizes a wide range of 5.56 NATO and .223 Remington bullet weights. The heavy profile adds rigidity and heat management, making it well suited for AR-15 pistol and short-barrel rifle configurations that see regular firing sessions.

This is a standalone barrel assembly sold as a direct replacement part or as a component for a custom AR-15 build. Whether you are completing a new pistol build, swapping a worn barrel on an existing Diamondback, or upgrading a donor upper, the DB Barrel delivers the rugged construction and precise rifling that Diamondback Firearms builds into its components.