I've reloaded 55gr. FMJ with up to 24.5 gr of TAC. I was very pleased. These were my first reloads. They worked flawlessly and the accuracy was better than any factory ammo I had shot yet. The barrell twist rates were 1/9 and 1/12. I will be working up some heavier loads for the 1/9 and some lighter (bullet weight) for the 1/12, it likes faster loads.Ok, just because nobody has mentioned them, I'll recommend Ramshot's X-terminator and TAC for .223 with bullets up to 62gr. I've been loading 55gr bullets with X-terminator and it performs very well. And I've read some very good things about TAC.