Check the diameter of your throats. They should be a min. of .357", with .358" being ideal. My 27-2's throats measure the later, and I have no issues with leading in them. I have had that though with guns with undersized throats, and throats that are too large by .003"-.004". I doubt that yors are oversized, but they could be undersized. Your load is listed on Alliants site, and isn't too warm, so possibly you need to bump it up a bit to obturate your bullets in the throats if they are on the soft side. Too soft, and too hard can both be problematic in regards to leading. What is your mixture/alloy?
