Stainless Steel, bead blasted (manf. by Sabre Defense) standard extension 1/8 twist 16" barrel Match chamber .223 (SDI uses xm193, Q3131, and 223 match ammo for testing. 5.56mm ammo is ok in this barrel) barrel weighs 1lb 10oz by itself Light profile under the guards fluted forward section carbine gas system 1/2x28 threads
