One of my projects a few months ago was to develop a good 308 win load using first 168gr Sierra MKHP and then the Hornady 168gr match HP. Granted I'm in Iowa and it took three range sessions in January to arrive at 42.5grs H4895 with these weights loaded in Federal 308 Win brass for 2700fps from a 26" barrel single shot, or 2480fps from a 16" semiautomatic. This load is a maximum load, but the most useful since I was hoping for 2500fps from the shorty, but this is close enough. I tried a few incremental loads such as 42.7, and 42.8, but I actually got lower velocity readings, so I backed off to 42.5 as my maximum useful load in an AR platform. I don't have an M1A, but given what I've seen this load should be safe enough in an M1A. If I were using military brass then it should be decreased.
It also appears Hornady is trying to beat Sierra at their own game with the 168 HP match bullet. The Hornady's are ever so slightly longer for a bit more B.C. and run a bit faster over the screens. Accuracy is almost equal with a very slim edge to the Sierras. The Hornady tested sub 1/2 MOA for 5 shots at 100yds from my 26" heavy barrel test platform
