Was up in Mendocino National Forest a few weeks ago camping out & celebrating my 61st b-day at a neat old Deer camp that's probably been in use for ages. Found a very old, damaged but live centerfire round that is marked REM UMC 22 HP loaded with a long .22 caliber round-nosed bullet. Tried searching and turned up no info - what'd I find and what's the cartridge's history?