Thursday, January 15, 2004
Copyright © Las Vegas Mercury

Gun basics

Don't know shoot about guns? Here's a layman's guide

Types of pistols

A revolver is a pistol in which bullets (sometimes called "cartridges") are placed into a revolving cylinder, which turns as the weapon is fired to bring a fresh cartridge underneath the firing pin. On most models, the cylinder swings out to be loaded. Depending on the caliber of the weapon, a revolver can have five, six, eight or sometimes more chambers in the cylinder, although most have five or six (hence the term "six-shooter").

A "single-action" revolver requires the user to pull back the hammer ("cocking" the pistol) before every shot is fired. Many pistols in the Old West were single-action, accounting for gunfighters "fanning" the pistol with their nonshooting hand to allow for rapid "cock-fire-cock" action.

A "double-action" revolver cocks the pistol automatically when the trigger is pressed, and then fires the weapon. Most of these revolvers may also be manually cocked.

A semiautomatic pistol, by contrast, stores bullets in a magazine that is generally inserted into the grip of the weapon. The magazine feeds bullets into a chamber in front of the firing pin. Semiautomatic pistols generally have more rounds than revolvers, which accounts for why most military and law-enforcement agencies switched from revolvers to semiautomatic pistols.

When a semiautomatic pistol is fired, the bullet leaves the barrel and the top part of the pistol, called the slide, ratchets back to eject the spent casing (which contained the primer and gunpowder) and feed a new round into the chamber. Only one round is fired each time the trigger is pressed.

(Although rare and more often seen in rifles, there are fully automatic pistols, which will continue firing as long as the trigger is pressed until the magazine, also known as a "clip," is empty.)

Rifles vs. shotguns

A rifle is a weapon with a long barrel, the inside of which has spiral grooves cut into it to ensure the bullet will spin as it travels to its target and not tumble, increasing accuracy. (Pistols have rifling inside their barrels for the same reason.)

Rifles, like semiautomatic pistols, are usually fed by a magazine, although the rounds tend to be much longer and more powerful than pistol rounds. Because of the length of the barrel and the size of the rounds, rifles are generally more accurate than pistols over longer distances.

Some rifles--such as the World War II-era M1 Garand--are semiautomatic, although more modern military weapons--such as the famous AK-47 or the U.S. military's M-16--are fully automatic. Other rifles, known as "bolt-action," require the user to pull back on a bolt to discard the spent round and put a fresh one into the firing chamber.

A shotgun, by contrast, has a smooth barrel and fires multiple, small projectiles contained in a larger shell. The effect is to scatter a number of these smaller pellets into the target. Shotguns are especially useful in hunting. (A few shotguns do have rifling to increase accuracy, especially those that fire a slug, a solid round not composed of smaller pellets.)

--Steve Sebelius