My .223 has a 1/14" twist, being a rechambered M722 .222 Rem. I use 24.5 grains onf IMR 3031 with a Sierra 55-grain flat-based bullet for 3350 FPS from a 26" tube. This shoots most bullets through the same hole @ 100 yards. It will not shoot boattials well, and GI loads are awful!!

Keep yore powder dry!!