Working on loads for my 280AI on a ruger 1 action. Have had good success with H4350 and 140 gr Sierra Prohunters-touching at 200 if I work at it and we are still under 200rds through the barrel-27" length. Unfortunately, not so impressed with the Barnes 140 TSX so far-not near as accurate as the Sierras. Tried some H4831 SC at 60 gr on the Sierras and not near as accurate as the H4350 or IMR 4064 at 45gr. the 4064 load shot comparable to the 4350. I am also starting to pack the 4831 at 60 grains with the Barnes bullets. I really want to stay with the 140 gr bullets and I have plenty of 4064 and think I know where I can get more H4350. So my questions are: How much IMR 4064 has anyone shot through a 280AI with a 140 gr bullet and how much H4350-just looking for the upper limits for the barnes since I understand they need to be a little hot for best performance. Thanks for any thoughts or experience with these.