Well, I stretched out my chosen A-max load some, and am quite happy with the results.
5 shots at 300 yds (1.3 mil elevation, .3 mil windage):
Unfortunately I think it may be a bit warm for my rifle. First inklings came when I chrono'd both the 168gr and 178gr loads I worked up. The 168 averaged 2664 fps, and the 178 averaged 2648 fps (despite having .7 gr less powder), both pretty stout out of a 20 inch tube.
Warning: Dumb ideas and bad practices to follow
I had been using some Winchester brass that I got once fired (in a semi-auto) from a buddy years ago to work up my .308 loads, but the primer pockets were somewhat loose on a portion, and I suspected I was getting some primer blowby staining my bolt. I was at the range getting my scope setting with this load yesterday when I was invited to a local informal long range match. I had to load up 50 rounds, and didn't want to run the risk of my old brass allowing blowby to etch my bolt, so I picked up 50 new Hornady brass and loaded it up for the match today ( I know, I know, bad idea). I've read Hornady match .308 brass is similar in capacity to Winchester, and I think it must be close as I was able to score first round hits at 500, 600, and 700 using my Winchester brass dope. On the down side, I think the Hornady brass has confirmed that my load is a bit over, as several of my fired cases show ejector marks. I think I'll pick up some new Winchester brass and try out some loads in the 43.5gr area, which also showed promise on the original OCW workup.
I hope new Winchester brass is the same capacity as older lots... What kind of .308 brass are folks having good luck with these days.