Tried H4350 behind 75 gr A-Max in my 26" Cut rifles BBL( 8"twist) in 22-250AI yesterday. MV was all over the place with each load combo. Tried 36.5 to 39.2 grs with fully prep casesFed Match primers. Seated to with in .005 0f rifling lands. Extreme velocity spreads in all combo's,36.5 grs gave good accuracy but low MV Average 3,125. 37.5 grs produce a 1/4"( 3200 MV) group with one bad flyer but extreme velocity spreads. Next was 38.5 ( 3,325)MV was all over and group opened up. Next 39.2(3,400MV) even worce MV spreads and poor accuracy. So what powder should I try next? I'm hopeing to get a 3,400FPS accurate load for long range coyotes???