44 40

The .44-40 Winchester (10.8x33mmR), also known as .44 Winchester, .44 WCF (Winchester Center Fire), and .44 Largo (in Spanish-speaking countries), was introduced in 1873 by the Winchester Repeating Arms Company. It was the first metallic centerfire cartridge manufactured by Winchester, and was promoted as the standard chambering for the new Winchester Model 1873 rifle. As both a rifle and a handgun caliber, the cartridge soon became widely popular, so much so that the Winchester Model 1873 rifle became known as "The gun that won the West."

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