The AR-10 Barrel is a 22" straight fluted heavy profile barrel made of 416R stainless steel, a rifle length gas system with a 1:8 twist rate. The barrel is chambered in 6.5 Creedmoor and machined with AR-10 feed ramps in the barrel extension. Length- 22"Profile Heavy Barrel Twist 1:8 Finish Stainless Material 416R Stainless Steel Thread Pitch 5/8 x 24 Caliber 6.5 Creedmoor Flutes Straight Flutes Gas System- Rifle Gas Block System 0.936