Fans of the Impact Precision 737 & 787 actions will be an even bigger fan of the PROOF Research Carbon Fiber pre-fit barrels designed for the popular Impact Precision 737R & 787 action. PROOF's Impact pre-fit barrels will arrive threaded/chambered with 5/8x24 muzzle threads. This is a shouldered barrel that requires few specialized tools for install. They're offered with a variety of caliber, lengths, and twist rates in Carbon Fiber.
* These Proof Research/Impact Precision 737R pre-fit barrels are pre-headspaced. However, it is always recommend to double check headspacing with proper gauges before firing a rifle.