I think H1000 with reg LRPrimers should work well with the 131Hammer,s . My load was 57.3 grs with N165 with LR primers , my vel was 3180 with a 25 in Bartlien . N560 , Rl26 N165 RL23 may work a little better if you run out of powder space . I think N560 is going too work well in several bullet weights . Also the knurls are called drive bands , they are designed too give you less parabolic drag with a gain in velocity. Tha last ladder test I did was with the 109 gr absolute , the test was done with 7 shots with half grain increments . Out of seven shots 6 were under .75 with 3 of those in the same hole . You can't over spin them and they are very acc . I was shooting 500 yds this weekend and I was impressed.