The priemier accuracy that I have attained from .223 in AR Platformed rifles. Twist varied from 1 in 7 to a 1 in 14, and all of the inbetweens. Has been a 55 grain Hornady V-Max. That bullet gave the best groups with a wide variety of powders in mixed cases with which ever primers I could find. Next in line behind that is 55 grain FMJBT Winchester. Cheap, and effective. No they do not give the accuracy that the VMax do. Though they get fairly close for about 30% less in cost
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.