I tried some loads of 405 Remington FNSP using large rifle CCI primers over 15.2 grains of Unique yesterday. I had several Failures to Fire even though the primers were clearly struck hard. Plus, among those that fired I had sticky extraction. The primers were not flattened and the brass looked OK but I think I was experiencing high pressure spikes. I put those loads away and will disassemble them this week. I am going to stick with my H4895 loads. They shoot dirty like Remington's trapdoor loads but are well-mannered and appear accurate.
T.S.
I experienced powder bridging throwing Unique in a rifle powder measure. I was trickling the last bit of powder so it was obvious right away. I broke out the old school Lee dippers, and dipped/trickled.
I don't know if you may have possibly been having powder bridging issues, but I have never had inconsistent ignition or indicators of pressure using Unique with the 405gr cast bullets.
