I got a new press, dillon 550b, and I've been setting it up for the past few days. I hope I've made every mistake that I'm going to make. I was loading some 9mm luger with 4.2 grains of powder. I got about 80 rounds into it, and I look down and see lots of powder. . .something like 6 grains. I dumped it out and loaded it and still got 6 grains. . . . I was pretty sure this was the first one, but I wasn't sure. I looked at the bin of just over 80 rounds of completed ammo. . . . Yeah I pulled them all. now I but the bullets in the plastic bins every 10 or 15 rounds I also put my primer pick up tube into my primer magazine that was entirely in place. . . . primers everywhere. I hope this is the last mistakes I'm going to make with this press, but I like the press a lot. It does seems to spit a little powder everywhere. (could be operator error). I'm also getting a little more variation in my OAL than I'd like. I might have to tighten my dies down a bit more. With luck, I'll stay away from any big booms. I work the progressive really slow. probably only about 150-200 rounds an hour, but I'd rather go slow and not blow anything up.