Thanks again Roscoe, I will contact RCBS and send a Cerrosafe casting to them. I miked an original .450 Nitro Kynoch unfired cartridge and 3/4" up from the base it is 10 thousands smaller than a case run through the Hornady dies. I thought the BPE rifles had different chamber specs, but the 1902 Webley .450 Nitro also would not chamber the Hornady sized rounds. I must say that Hornady customer service was excellent and immediately sent me a second sizing die to try.