My sister, who pokes around in Idaho ghost towns, has found a somewhat unusual cartridge case. I do not have the actual case, so cannot supply any measurements (as yet). The case is head-stamped (starting from 12 O’clock and going clockwise): C, 80, F, 3. In addition it exhibits a centerfire firing pin
impression, but absolutely no trace of a primer. It looks like a straight wall rimmed case, like an upsized .22 Long Rifle.
Kent, Washington, USA