Proof Research Accuracy International Pre-Fit Barrel Carbon Fiber 308 Win 16.5 inch 1/10 Twist 5/8x24 Thread M27 Breech Thread Black. You also need a barrel that will perform in extreme heat or cold. The PROOF ACCURACY INTERNATIONAL Pre-Fit Carbon Fiber Barrel is the solution for creating a top-quality gun barrel that will allow you to shoot much more than you ever thought possible. The combination of aerospace-grade carbon fiber and pre-hardened 416R stainless steel offers unparalleled performance in any situation and these are pre-fitted meaning they are ready to go out of the box and put on your guns. The PROOF Accuriance International Pre-Fit Carbon Fiber Barrel requires no thresh-grinding which means that there is no burr or rough spot to ruin your shot. Specifications for Proof Research Accuracy International Pre-Fit Carbon Fiber Barrel: Manufacturer: Proof Research Color: Black Threads per Inch: 5/8x24 Gun Make: Accuracy International Condition: New Package Contents: Proof Research Accuracy International Pre-Fit Carbon Fiber Barrel What firearm models does the manufacturer say Proof Research Accuracy International Pre-Fit Carbon Fiber Barrel is compatible with? The manufacturer says that Proof Research Accuracy International Pre-Fit Carbon Fiber Barrel is compatible with Accuracy International AT Accuracy International AXProof Research 109298: Accuracy International Pre-Fit Barrel Carbon Fiber 308 Win 16.5 inch 1/10 Twist 5/8x24 Thread M27 Breech Thread Black