Product Description The CMMG Barrel Sub-Assembly is purpose-built for those looking to construct a custom Mk3 or High Pattern LR-308 upper group. Chambered in .308 Winchester and measuring 20 inches in length, this barrel is crafted from 416 Stainless Steel and finished with a Salt Bath Nitride (SBN) coating for outstanding corrosion resistance and durability. Each barrel sub-assembly comes with a properly installed M4 barrel extension and is headspaced to factory specifications right out of the box, ensuring reliable, accurate performance. With a medium taper (MT) contour, a 1:10 twist rate, and a rifle-length gas system, this barrel delivers the balance of weight, velocity, and reliability that .308 Win shooters demand. The threaded muzzle (5/8x24) allows for the addition of muzzle devices, and the 0.750" gas block journal accommodates standard-diameter gas blocks. Product Highlights Ready-to-Install Precision: Comes with a properly installed M4 barrel extension and is pre-headspaced for immediate use in your LR-308 / Mk3 upper build. 416 Stainless Steel Construction: Machined from premium 416 Stainless Steel for superior strength, heat resistance, and longevity. Salt Bath Nitride (SBN) Finish: Enhanced surface hardness and corrosion resistance through a Salt Bath Nitride treatment, extending the service life of the barrel. Rifle-Length Gas System: Features a rifle-length gas port location for smooth, reliable cycling and reduced felt recoil in .308 Win configurations. Threaded Muzzle and Standard Gas Block Journal: 5/8x24 muzzle threading and a 0.750" gas block journal provide broad compatibility with suppressors, muzzle brakes, and standard gas blocks. Specs Brand: CMMG Platform: Mk3 / High Pattern LR-308 Caliber: .308 Winchester Barrel Length: 20" Barrel Twist: 1:10 Barrel Contour: Medium Taper (MT) Barrel Material: 416 Stainless Steel Finish: Salt Bath Nitride (SBN) Muzzle Thread: 5/8 x 24 Gas Port Location: Rifle Gas Block Diameter: 0.750" Weight: 2.4 lbs UPC: 816422026821 MPN: CMM38DDA0C 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.