Proof Research PXT Sendero Barrel Blank Features The Proof Research PXT Sendero barrel blank is built around PROOF s Exponential Twist rifling geometry a complete rethinking of conventional twist progression engineered to reduce engraving force and minimize throat erosion as a bullet engages the rifling. By smoothing the transition into the bore PXT technology reduces wear and felt torque during firing helping shooters stay on target through strings of fire. Machined with a 1 in 10 inch twist rate and 5 grooves the barrel is cut for .308 Win and supplied as a blank ready for a custom build. Controlled testing has shown PXT barrels delivering a 30 to 100 percent increase in barrel life over conventional rifling while maintaining PROOF s expected accuracy standards. Built around PROOF s proven carbon fiber construction the Sendero contour blank offers an exceptional stiffness-to-weight ratio trimming overall rifle weight without giving up the stability a precision barrel needs. At 18 inches long with a 2.5 inch breech and a 1.20 inch shank diameter the blank is sized to fit a wide range of custom actions and gunsmith setups. This barrel is intended for custom rifle builders and gunsmiths constructing lightweight hunting rifles precision long-range rigs or modern high-performance rifle builds where consistency matters most. For builders who want the combination of PXT rifling technology and carbon fiber construction in a .308 Win blank the Proof Research PXT Sendero is available for sale at GrabAGun. Proof Research PXT Sendero Barrel Blank Specifications Manufacturer: Proof Research Model: PXT Sendero Barrel Blank Caliber: .308 Win Action: Bolt Barrel Material: Carbon Fiber Finish: Stainless Twist Rate: 1:10 Grooves: 5 Barrel Length: 18 Breech: 2.5 Shank Diameter: 1.20 Contour: Sendero Weight: 2 lbs 13 oz Available At: GrabAGun