Cmmg Bbl 300blk 16.1" Mt 416ss

The CMMG Barrel 300 Blackout 16.1" Mount 416 Stainless Steel is a precision-engineered upper receiver component purpose-built for custom AR15 platform assembly. This 300 Blackout barrel features a pre-installed M4 barrel extension and arrives properly headspaced, eliminating guesswork during upper assembly and delivering out-of-the-box reliability for shooters building dedicated .300 BLK carbines.

Constructed from 416 stainless steel with a medium taper profile, this barrel combines corrosion resistance with a balanced weight-to-rigidity ratio ideal for both suppressed and unsuppressed shooting. The 1:7 twist rate stabilizes the full spectrum of .300 Blackout ammunition, from lightweight supers to heavy subsonic projectiles. The 5/8x24 thread pitch accommodates standard suppressors and muzzle devices, while the carbine-length gas port with .750" gas block journal ensures consistent bolt cycling across ammunition variations. Proper headspacing at the factory eliminates the need for additional gunsmithing or headspace gauging, a critical advantage when building precision upper assemblies.

This barrel serves shooters and tactical professionals building dedicated .300 Blackout uppers for duty, training, or specialized applications where subsonic capability is essential. The 16.1" length balances velocity retention with maneuverability in confined spaces—critical for close-quarters work. The pre-assembled, headspaced configuration saves assembly time and reduces the risk of installation error, making it ideal for builders prioritizing reliability over custom gunsmithing.

CMMG's commitment to precision manufacturing ensures that this barrel maintains tight tolerances throughout its service life. The 300 Blackout cartridge has become the standard for suppressed rifle applications across military and law enforcement units, and this CMMG barrel delivers the accuracy and reliability that mission-critical shooting demands.