Proof Research Carbon Fiber AR 15 Barrel 6mm ARC 18" 128671

Engineered for shooters who demand precision without the weight penalty, this 18" PROOF Research barrel pairs a 1:7.5 twist rate with a rifle-length gas system for smooth, reliable cycling across a range of loads.

Key Specifications:

• Length: 18"
• Twist Rate: 1:7.5
• Gas System: Rifle length, +1
• Gas Journal: .750"
• Port Size: .096"
• Muzzle Thread: 5/8-24
• Weight: 1 lb 14 oz

Built on PROOF Research's signature carbon-fiber-wrapped construction, this barrel delivers match-grade accuracy in a package significantly lighter than a comparable steel barrel — reducing overall rifle weight without sacrificing rigidity or heat dissipation. The carbon fiber jacket helps dissipate heat faster than steel alone, minimizing point-of-impact shift during sustained or high-volume fire, while the tuned gas system length smooths recoil impulse and improves cycling reliability.

The 5/8-24 muzzle thread pitch supports a wide range of muzzle devices and suppressors, and the .750" gas journal with .096" port size is calibrated for consistent, reliable operation with this gas system configuration.