I've gotten several obscure calibers going again but this one is a new level. I've got an old combo/drilling made by a German wildcatter around the turn of 1900. After doing a casting of the chamber, the case is basically a 43 Mauser trimmed down to total case length of 2.00". I started a post around 2 weeks ago and got some great help on possible cartridge identity and how a couple other people encountered the same obscure caliber and managed to recreate and reload it. Problem is, mine seems to be even odder than theirs as I have run into a major conundrum that they didn't. According to the casting, the wildcatter apparently trimmed down a 43 mauser to 2.00 inches, but then expanded the outer neck diameter to .480". I have no idea what his goal was in doing that, but basically, the perfect diameter for a 45 caliber boolit. So I expected to find that the barrel was 45 caliber. The hurdle is that the barrel slugs to .430" and has a .440" groove diameter. So, ok, I could probably use a .430 cast boolit in that barrel and be fine. But how do I get a .430" boolit to sit in a case with a .480" outer neck diameter?