I found an old cartridge case with no headstamp. It looks like a .45-70 round but the dimensions are wrong. A .45-70 has a case neck of .487" but this round has a case neck of .480". The case length of a .45-70 is 2.105" but the mystery case is 1.848". I don't know if it might be a line-throwing blank or a foraging cartridge they used in the .45-70. The foraging round had a hollow wooden bullet filled with shot. Trouble is that I can't find any case lengths listed for either of them.
Anyone got any ideas because I'll admit I'm stumped?????????