Something to watch is your choice of the "plug" used in bullet seating. Many are double ended with a "flat end" and a "round end". Obviously one for Round Nose and one for SWC/WC/Truncated cone, or so you'd think. I while a go I had a problem with Berry's Plated 185 gr flat point bullets. For a reason I was unable to detect using the "flat" plug resulted in a bulge near the case mouth that would prevent the cartridge from chambering. That was solved when I switched to the Round plug.