For sale is my CarbonSix, 1:8 twist, 20” long, 5/8” muzzle thread, Sendero profile, shouldered prefit for a bighorn origin chambered in 30 Sherman Magnum (300 prc a.i.). Barrel has 542 rounds on it. It will run factory hornady 300 PRC 225 Match ammo at 2700 fps, and I was loading 245 eols at an...