The 25-20 Winchester (25-20 Winchester Center Fire or WCF) is based on the 32-20 Winchester case necked down to 25-caliber. It was introduced in about 1894 in Winchester's short-action Model 1892 lever action, and was subsequently offered in numerous lever-action and slide-action rifles. The 25-20 is a mild cartridge propelling an 86-grain bullet at 1460 fps. Although it has been used for deer it is under-powered for any big game; it's at is best for small game and pests at fairly close range--and is a fun cartridge to shoot!