Product Description The Proof Research 138687 is a precision-engineered carbon fiber wrapped rifle barrel chambered in .308 Winchester, combining exceptional lightweight construction with outstanding accuracy and durability. At 16.5 inches in length with a 1:10 twist rate, this barrel is purpose-built for AR-10 and compatible semi-automatic platforms seeking a compact yet capable setup. The 5/8-24 threaded muzzle enables seamless integration with suppressors, muzzle brakes, and other muzzle devices. Proof Research&';s signature carbon fiber wrapping technology not only drastically reduces overall weight compared to traditional steel barrels but also improves thermal dissipation during sustained fire, keeping the shooter accurate over extended sessions. Whether for hunting, precision competition, or tactical use, this barrel delivers elite-level performance in a package built to last. Product Highlights Proprietary carbon fiber wrapped construction dramatically reduces weight while preserving barrel stiffness and precision Chambered in .308 Winchester, offering proven versatility for hunting, competition, and tactical applications 16.5-inch barrel length delivers a compact, maneuverable profile without sacrificing ballistic performance 1:10 twist rate efficiently stabilizes a broad range of .308 Win projectiles for consistent accuracy 5/8-24 threaded muzzle is ready for suppressors, muzzle brakes, and compensators straight from the factory Specs Brand: Proof Research MPN: 138687 UPC: 843068138687 Caliber: .308 Winchester Barrel Length: 16.5" Twist Rate: 1:10 Muzzle Threading: 5/8-24 Construction: Carbon Fiber Wrapped Disclaimer: We strive to provide accurate and up-to-date product descriptions, specifications, and images; however, errors or omissions may occasionally occur. We are not responsible for any inaccuracies or discrepancies in the content provided. If you notice anything incorrect or unclear, please contact us so we can correct it. When in doubt, we recommend verifying details directly with the product&';s manufacturer.