.38 S&W (Smith & Wesson) is a centerfire revolver cartridge designed by Smith & Wesson in 1877. It is also known as the .38 Colt New Police, or 9x20mmR.
The .38 S&W cartridge is typically loaded with a 145-grain bullet and has a muzzle velocity of around 600 feet per second. It is not a particularly powerful cartridge, but is known for its accuracy and ease of use, making it a popular choice for target shooting and small game hunting.
The .38 S&W cartridge was widely used in the late 19th and early 20th centuries, particularly in small, pocket-sized revolvers. It saw extensive use as a backup or self-defense weapon, particularly among law enforcement and civilians who needed a small, easily concealable firearm.
Today, the .38 S&W is less commonly used, as more powerful cartridges have become more readily available. However, it is still popular with collectors and enthusiasts, and is occasionally used for target shooting, small game hunting, or as a backup gun for personal protection. It is important to note that the .38 S&W cartridge is not interchangeable with the more common .38 Special cartridge, as they have different case lengths and diameters. Attempting to use .38 S&W ammunition in a .38 Special revolver, or vice versa, can result in malfunction or damage to the firearm.