The MPR is available in various barrel lengths from 16 inches to 27 inches, and it's chambered in 6.5 Creedmoor, 6.5 PRC, .308 Win., .300 Win. Mag., .300 Norma and .338 Lapua. Not all barrel lengths are available in all cartridges. Each barrel is threaded with a 5/8x24 pitch and fitted with a removable, tunable stainless side-baffle brake. 2022. 6. 14. · This .300 Win Mag rifle features 24 chrome moly barrels with a 1:10 twist. It is 5/8 by 24 threaded and incorporates the brand’s muzzle brake, which is known for its impressive recoil control. Regardless of the environment and weather conditions, you can count on this rifle’s top-of-the-line performance, thanks to its patented V-block aluminum stock and bedding. Nov 01, 2021 · A high quality rifle in .300 Win Mag, like this Tactical Rifles Chimera, is capable of excellent accuracy at distances beyond 1,200 meters. To show what a .300 Win Mag is capable of I put mine to work on the range. It is a Tactical Rifles build using their Chimera Magnum length action. Riding inside this is a fluted bolt with an oversize knob..