.38-40
.38-40 Winchester
American pistol cartridge
The .38-40 Winchester (10.17x33mmR) is actually a .40 caliber (10 mm) cartridge shooting .401 in (10.2 mm) caliber bullets. The cartridge was introduced by Winchester in 1874 and is derived from their .44-40 Winchester. This cartridge was introduced for rifles, but in its reintroduction for cowboy action shooting it has seen some popularity as a revolver cartridge. It is not particularly well suited to hunting larger game, but it was popular when it was introduced, along with the previous .44-40 Winchester, for deer hunting. It can be used successfully on smaller game animals, and for self-defense. Current loadings are intended for revolvers.[3]