I developed a load several years ago when I had two ARs. I wanted a load that worked out of both. One was a 1:7 and the other was 1:9. I found the 69gr SMK with .2gr over the target load listed for Varget in the Sierra manual's AR section. Worked great. I also shoot 55gr Vmax as well as the 70gr speer semi point. I try to load up ammo that will shoot well out of both so I can save time.