Well, I want to thank Steve for all of the help and advice that everyone gave me over the past year or so. I finally loaded and shot my first reloads, and I wasn't nervous about them working at all, because I took my time and double checked my work. Because I am using the Lee Pro powder measure, I'm not able to do the fine-tune adjustments like I would like to. Precision Delta 124gr, 4.0gr Win 231, CCI SPP #500, COAL = 1.158" Precision Delta 124gr, 4.3gr Win 231, CCI SPP #500, COAL = 1.160" Mixed brass The first batch I only loaded 10 rounds, because I had a feeling the 4.0gr's wasn't going to be enough to cycle my EMP, which was right. They failed to eject every single time, and failed to lock the magazine back. The second batch I loaded 50 rounds, and they did a lot better. They all cycled perfectly, however 2 out of 10 magazines failed to lock back, and I have no idea why...any advice? I know the 1.160" OAL is a probably pushing the limits, but I measured WWB at 1.158" and they work perfectly in the EMP. Ignoring my bad shooting and fliers, these were at 7 yards. I had my forearms on a bench and my hands in the air, kind of a terrible position. It's obvious that the first batch won't due, and it appears that if I take my time and aim, the second batch will be pretty accurate with mild recoil. 4.0gr: 4.3gr: So now the big question...should I try the next size disk? It says it's 5.0gr's, which is the max load according to my Speer book. I'm starting to understand why you all told me to buy 1lb of powder and keep trying different ones....well, of course I didn't listen and I have 4lbs of Win 231. Should I stick with the 4.3gr load and see how it does in a USPSA match? Reliability is huge for matches (obviously), and I'm concerned with the 2 failures to lock back the magazine. Should I try reducing my OAL slightly?