BRT gets it
https://blackrivertactical.com/WP/BRT-8-0-OPTIMUM-Hammer-Forged-Chrome-Lined-Barrel-300BLK-PDW-p440556374 1/5 Twist for improved terminal performance of expanding subsonic projectiles. Also provides enhanced stability with long, heavy subsonic projectiles through suppressors.30 Caliber Feed Ramps for reliable feeding of heavy round nose and hollow point expanding subsonic loads.
Gas System tuned for reliable operation in all 4 modes:
Subsonic
Subsonic Suppressed
Supersonic
Supersonic Suppressed
300 BLK Chamber for compatibility with all supersonic and subsonic ammunition. Our multi-step process produces true SAAMI-spec chamber dimensions with excellent concentricity and includes separate operations for throating and chamber polishing.
Hammer Forged for extreme durability and accuracy. Our precision hammer forging process produces an exceptionally straight and smooth bore finish with ideal land and grooves profiles, all of which are key to maintaining accuracy. The forging process also increases hardness and produces beneficial grain flow alignment which improves toughness.
Chrome Lined Chamber and Bore for excellent service life and resistance to corrosion. Our industry leading process was developed specifically to address the unique requirements of precision firearm barrels and includes 5 key improvements to ensure highly uniform and accurate results. This includes an electro-polishing treatment before chrome lining.