My 9 twist 22-250 loves the 75 Amax over IMR4350. Trouble is I couldn't find any more than the partial box I was given, so I've been shooting the 69grain Sierra MatchKing BTHP and they do very well too. As soon as I can find the Amax again I'm getting a 600 brick of them. Once this barrel is gone though I'm getting an 8 Twist AI version to replace it with just because.

My 26" barrel is shooting the 75 gr. Amax only ~200 FPS slower than my 22" barrel 25-06 pushes the 75 grain Vmax, but with much less recoil, and 19.7 grains less powder.