.38-55 Winchester

The .38-55 Ballard later called .38-55 Winchester, or in metric terms 9.6x53mmR (actually .3775 caliber), is a Straight-walled centerfire rifle cartridge based on an earlier .38-50 Ballard Everlasting cartridge introduced in 1876 by the Ballard Rifle & Cartridge Company. First chambered by Ballard and Marlin Firearms, then it was later offered by Winchester in its Model 1894, who usurped the name, designating it the 38-55 WCF, although it was an exact dimensional copy of the 38-55 Ballard. Winchester then re-labelled it again, calling it the .38-55 Winchester in their Model 1894 rifles. .

The .38-55 Ballard was originally a Black-powder cartridge as used in Ballard and Marlin Firearms from 1876 onwards for various single-shot target rifles. Marlin's 1893 lever-action rifle was also available in 38-55 using a Black-powder only barrel, or another barrel designated "Special Smokeless Steel" capable of safely using 38-55 cartridges loaded with the then relatively new and higher pressure smokeless powders. Marlin offered it later in some Model 336 rifles as well.

Winchester continued to use the round in various rifles until about 1940, and also used it in a few commemorative editions of rifles since then. In addition, it was used in non-lever action rifles such as the Remington-Lee bolt-action. The .38-55 Winchester is also the parent case for the .30-30 Winchester, .32 Winchester Special, and the .375 Winchester cartridges.

A modernized version of the cartridge debuted in 1978 as the .375 Winchester, designed with higher pressures and to be used in modern firearms only. It is not safe to fire factory .375 Winchester ammunition in rifles chambered in .38-55, especially in older examples. The brass is very similar (shortened by approximately 1 mm (.0394 in)), but using modern, higher pressure .375 loads in an older rifle could cause serious injury to the shooter.

The .38-55 is used to hunt black bear and deer at moderate ranges and is also used in cowboy action shooting side matches.