Well reloading for 9 major will exceed sami spec first of all. Secondly powder does matter you want a slow powder but too slow. Like HS-6, Autocomp, Trueblue, Silhouette, N350, N340, 3n38, 3n37, AA7 etc. There are tons of data on eons where to start loading it. OAL depends on the person I usually do ~1.16 and for powder is whatever you can get your hands on or what feels the best. You need to make 165 PF for major also. So about ~1375 FPS with 124 GR bullet