.32-40 Win.

The .32-40 Winchester, also known as the .32-40 WCF (Winchester Center Fire), is a centerfire rifle cartridge developed by the Winchester Repeating Arms Company in the late 1800s. It was designed for use in lever-action rifles and was based on the same case as the .38-55 Winchester, but necked down to accept a smaller, .321-inch bullet.

The .32-40 Winchester cartridge typically fires a 165- or 170-grain bullet at a muzzle velocity of around 1,800 to 2,000 feet per second, delivering moderate energy and stopping power at medium ranges. It was designed as a hunting cartridge for use on medium-sized game such as deer and black bear, and it gained a reputation as an effective and versatile cartridge for hunters.

However, the .32-40 Winchester was not as popular as some of Winchester's other cartridges, such as the .30-30 and .45-70, and it was eventually discontinued in the early 1940s. Nonetheless, it remains a historical and collectible cartridge, and is occasionally still used for hunting by enthusiasts of classic lever-action rifles.