I just stick with what works. I have two of these in this caliber. One is set up for 140 Accubonds, the other 160 Partitions. I tried a number of different powders in with the 140s. However IMR 4831 58.0 grains with a Federal 210 works the best. Sub 1" groups at 200 yards. I can max it out at 60 grains but they spread out. Getting 3150 fps. Seat the bullet at 3.250. for what its worth...
