The Puritan 5.56 barrel is for Direct Impingement rifles and constructed from mil-spec 4150 chrome vanadium steel and features a 5R rifling profile with 1:8 twist rate. The gas port is set up for a mid-length configuration gas system. We have also installed the Patented E² extraction technology which increases the life on the extractor, increases reliability through dual extraction and makes shooting coated ammunition a breeze. To finish it off, our barrels are nitride heat treated, which greatly increases surface hardness and makes for a beautiful black and corrosion resistant finish.