I posted this in the reloading forum as well.
First time this has happened to me. I just got a 45-70gg and was working on some loads. I had worked my way up to 51.5 gr of 3031 and a 405gr rem. and had shot about 10 rounds when one ruptured. There was no sign of excesive pressure prior, the loads should be around 27000cup. All the brass was new winchester. Any ideas what I did wrong?
Chris