Smith and Wesson introduced the .38 S&W in 1877. Don't confuse the .38 S&W with the .38 Special. The cartridge of the latter is skinnier and longer and more powerful. The .38 S&W has been called other names, including: .380 Rim; .38 New Police; Belgian 9mm Revolver; and .38 S&W Corto.
A popular cartridge for handguns in its time, the .38 S&W was used most notably by the British military where it was called the .38/200. This expressed the caliber of the cartridge and the bullet weight in grains. The diameter of the bullet was 0.36" and the overall cartridge length was 1.2 inches, not enough for the .38/200 to perform very well. Muzzle velocity approached 620 feet per second, and muzzle energy was less than 200 foot pounds.
Though lacking power, the cartridge does have qualities desirable for a good pistol round. It is accurate and reliable with mild recoil. The innovation of the .38 S&W was using a fairly large bore cartridge for small to medium size revolvers. A good example of this is the Safety Hammerless model, a top break revolver that was introduced by Smith and Wesson in 1887. These pistols, sometimes called the “Lemon Squeezer”, were popular for concealed carry, pest control and plinking.
The .38 S&W bears the unfortunate distinction of being used in the attempted assassination of two presidents. James Garfield was shot twice in 1881 by Charles Guiteau with a .38 S&W caliber revolver. President Garfield walked away from the train station where he had been shot, but he was killed by infection of his wounds eighty days later.
President Theodore Roosevelt was also shot with a .38 S&W revolver. The assassination attempt was made by John Schrank as President Roosevelt was preparing to make a speech. The bullet was slowed by his steel-reinforced glasses case and the folded notes for the President's speech, which ran over 50 pages and were stuffed in his jacket pocket. These two items asborbed enough energy that the President was able to speak for ninety minutes before going to the hospital. Teddy lived, but was not re-elected for a third term.
.38 S&W ammo is not as popular as it used to be, though at least four major manufacturers still produce the cartridge. Lead round nose bullets are the most common, but it is possible to find full metal jacket bullets and even some hollow point ammo.