Adds history and replacement of weapon by law enforcement

By Tim Reid

Nov 27 (Reuters) - The handgun used in the ambush of two National Guard members in Washington, D.C., on Wednesday was a .357 Smith & Wesson revolver, Jeanine Pirro, the U.S. Attorney for the District of Columbia, said on Thursday.

Here are five facts about the weapon.

IT'S A POWERFUL HANDGUN

The handgun, which was first introduced in the 1930s, is typically a six-shooter revolver that fires rounds at a high velocity and has been popular with law enforcement officials for its stopping power and ability to penetrate vehicles. It was designed to be powerful by firing larger ammunition at higher velocities.

THE .357 SMITH & WESSON IS RARELY USED IN PUBLIC SHOOTINGS

The gun, which has limited ammunition capacity compared with semi-automatic pistols that can carry 10-17 rounds or more, is rarely used in public or mass shootings. It is more commonly used for target practice or hunting small to medium game.

IT IS SIMILAR TO BUT NOT THE SAME AS THE .44 MAGNUM MADE FAMOUS IN THE 'DIRTY HARRY' MOVIES

The .357 Smith & Wesson is a Magnum handgun, meaning it can fire a high-powered cartridge. It was the original Magnum handgun. But the power and recoil of a .44 Magnum, made famous by Clint Eastwood in his fictional portrayal of Inspector "Dirty" Harry Callahan in the 1970s and 1980s police drama franchise, is significantly higher.

HANDGUN INTRODUCED AFTER PROHIBITION

The .357 Smith & Wesson was introduced in 1935 shortly after the end of the Prohibition era, when the mafia and other organized criminal groups had gained considerable power in the U.S. over the battle to control the illegal alcohol trade. The gun was designed primarily for police to give them more firepower.

IT BECAME A GO-TO HANDGUN FOR LAW ENFORCEMENT

For decades after its introduction, the .357 Smith & Wesson was the handgun of choice for most U.S. law enforcement officials. In recent years it has been replaced by even more powerful, semi-automatic handguns for police.

(Reporting by Tim Reid; Editing by Leslie Adler and Diane Craft)

((Timothy.reid@thomsonreuters.com; Reuters Messaging: tim.reid.thomsonreuters.com@reuters.net))