.38 S&W

The .38 S&W is a revolver cartridge developed by Smith & Wesson in 1877. Though similar in name, it is not interchangeable with the later .38 Smith and Wesson Special due to a different case shape and slightly larger bullet diameter.

The British military adopted a loading of this cartridge as the Cartridge, S.A., Revolver Ball, 380 in, MkI .38-200, with the "200" referring to the weight of the bullet in grains. In 1937, this cartridge was replaced in British Service by the Cartridge, S.A., Revolver Ball, 380 in, MkII. The main difference between it and the previous round was that that it had a 178 gn. FMJ bullet.

U.S. Variants
The .38 Colt New Police was Colt's Manufacturing Company's proprietary name for what was essentially the .38 S&W with a flat-nosed bullet.

The U.S. .38 S&W Super Police cartridge was nearly identical to the British .38/200 Mk I, using a 200 grain (13 g) lead alloy bullet with a muzzle velocity of 630 ft/s (189 m/s) and a muzzle energy of 176 ft·lbf (239 J), and was supplied by several U.S. manufacturers to the British government as equivalent to the Mk I loading.

The .38 S&W is also called the .380 Rim and .38 S&W Corto.

Current Status
Currently no revolvers are made in this caliber, and only a few companies still manufacture ammunition. The majority that do offer it in only a 145 grain Lead Round Nose bullet, though Fiocchi still markets FMJ rounds. Some companies such as Buffalo Bore manufacture self-defense or hunting variants.