Winchester rifle cartridge I need input on


My guess is that it is a reload where they crimped the daylights out of it forming the neck


The very distinct shoulder makes me wonder if a .40-65 WCF could be fired in a .40-70 WCF. If so, the neck would come up short, but likely could serve as a reloadable case for lack of the less popular .40-70. The shoulder on the .40-70 WCF should start a little less than 1-3/4" from the base.

Interesting cartridge!