Ramshot website's Load Guide. Click load guide on the left sidebar, then scroll down to rifle data, .223 (watch the right side), Pg 7. The data for the 1:7"-1:9" barrels are based on a 24" barrel, so your results will likely be slower. TAC is their recommended powder for the AR/69gr, I would use Big Game for 69-80gr bullets in a <span style="font-style: italic"><span style="font-weight: bold">bolt</span></span> gun. I have gone with 26.5gr of Big Game and the HDY 75gr HPBT Match in a 24" Sav 10FP, but I suspect Big Game may not be as compatible with gas systems and heavy bullets.