INTRODUCING THE BEGINNER TO FIREARMS

This is an introduction intended to introduce a beginner to firearms; with information designed to help you decide your needs and what firearms and ammunition meets those needs.

What is a gun?

A gun, or more properly a firearm, is a tool designed to accelerate an object (the bullet) to a relatively high velocity, and propel it with a significant degree of accuracy to impact a distant target. The target can be paper, clay, steel, or a living being. The expected distance to the target, the type of target, and the desired effect on the target will all shape the best type of firearm and ammunition to use, as will other concerns like size, weight, and cost, and the shooter's abilities.

Basic terms

• Bullet, slug, pellet The projectile fired from a firearm, generally consisting primarily of lead or some other dense metal. Bullets are fired from rifles and handguns, slugs and pellets(see shell) from shotguns.
• Cartridge A self contained unit containing primer, gunpowder, and bullet, generally held in a metallic or plastic case.
• Ammunition Collective term for multiple cartridges
• Round Singular for a cartridge
• Magazine A spring-loaded container for feeding cartridges into a firearm's chamber
• Clip A device for holding cartridges; also commonly (though incorrectly) used as a synomym for magazine
• Chamber Where the cartridge is held when it is fired; generally part of the barrel except in the case of revolvers.

Types of guns

Guns are generally divided into 3 broad classes; rifles, shotguns, and handguns. Often rifles and shotguns are lumped together as long guns. Handguns are often more tightly restricted than long guns, due to their smaller size and easy concealability. There are also machine guns and Submachine Guns, which are often preferred by Militaries & Law Enforcement agencies.

Rifles

A rifle takes its name from the rifling, or spiral grooves cut on the inside of the barrel. These grooves spin the bullet, and provide stability to keep it from tumbling as it flies through the air. Firearms without rifling generally fire spherical projectiles, which tumble in random directions (like a knuckleball) as they fly, and thus are fairly inaccurate. By adding rifling, not only is the random tumbling replaced with a consistent behavior in flight, but the bullet's shape can vary widely. In particular, rifling allows a long, thin bullet to be used to reduce air resistance, and the presence of a distinct front and rear allows the bullet to be constructed for maximum aerodynamic efficiency, or to allow specific structural features (more on this later under Terminal Effects).

In addition to the rifled barrel, the word "rifle" also implies a relatively long barrel and a shoulder stock, allowing the rifle to be supported at 3 points; both hands and one shoulder. This 3 point support allows the shooter excellent control over the rifle, and makes rifles relatively easy to shoot accurately. Most rifles have barrels of about 20 to 26 inches in length. A rifle with a shorter barrel than that is often called a carbine. Under US law, the minimum barrel length for a rifle is 16 inches; shorter than that and it is classified as a short barrelled rifle and subject to restrictions similar to those that apply to machine guns.

Rifle bullets are capable of very high velocities, up to 4200 feet per second in the case of the .204 Ruger, the current fastest commercial cartridge. Readily available bullet diameters range from .17 inches to .50 inches; while larger calibers do exist, they are considered under US law to be destructive devices and are subject to restrictions.

Shotguns

A shotgun takes its name from the fact that it is designed to fire shot, a large number of pellets that are smaller than the bore diameter. Shotguns do not generally have rifling, unless they are special slug guns designed to fire special shotgun slugs, which are basically large bullets. Firing shotshells through a rifled barrel with spin the shot and make it spread faster than normal, which is undesirable in most cases.

A smoothbore shotgun barrel generally isn't a straight cylinder, but contains a constriction at the muzzle end, called a choke, that changes how much the shot spreads upon exit from the barrel. A barrel with no choke is called a cylinder bore, and provides the greatest spread, while a full choke provides a large degree of constriction and much smaller diameter patterns. Shotguns designed to shoot at small, fast moving targets should use the most open choke that provides a sufficient density of pellets to guarantee a hit at the appropriate range. Short ranges, then, call for open chokes, while long ranges call for tighter chokes. Most modern shotguns are available with screw-in chokes, which allow the shooter to change the constriction by simply unscrewing one choke and screwing in a new one. A double-barreled shotgun provides the shooter the ability to have two different chokes, one for short range and one for long range.

Shot pellets used in shotshells is broken into two basic classes; buckshot are large balls that are stacked into the case one by one, while birdshot is much smaller and poured into the case by weight. Birdshot is used, as the name implies, for birds, as well as clay targets. Buckshot again, as the name implies, is used for hunting larger game such as deer, as well as for military and defensive use. The larger the number, the smaller the shot size. #12 shot is commonly found in .22 caliber cartridges, and is called rat-shot. #9 is generally the smallest used for hunting game birds or shooting clay targets. Larger sizes are used for larger game and longer ranges, and the largest sizes, like BB, T, TT, and TTT are found in steel shot used for hunting waterfowl (lead shot is banned for waterfowl due to the likelyhood of ingestion by birds). Buckshot starts at #4 buck, and goes past #1 to 000 (called "triple-ought") and, rarely, 0000. 00 is the most commonly used type by military and police, and is .33 inches in diameter.

There are two types of slugs available for shotguns; rifled slugs and saboted slugs. Rifled slugs have spiral grooves, resembling rifling, cast into the outside of the slug, and are designed with a deep hollow in the rear. The combination of weight-forward design and spin introduced by air traveling past the grooves and imparting spin provide stability from a smooth barrel. Saboted slugs use smaller diameter projectiles in a plastic shell, the sabot, that drops off after the slug exits the barrel. Saboted slugs generally must be fired from a rifled barrel, as they have no other means of providing stability.

Handguns

Handguns, like rifles, have a rifled barrel and are designed to fire a single bullet at a time. Handguns are by definition designed to be held and fired with one hand, although a two handed hold is usually possible and will be far more accurate. Handguns are more difficult than long guns to shoot accurately, due to the lack of a stock, and the resulting lack of control. Handguns are generally designed to be much lighter and more portable than rifles, though handguns used for long range target shooting or hunting may have barrels up to 14 inches or more. A handgun designed for easy carry will generally have a barrel under 6 inches in length, and weigh 2 to 3 pounds. Because of the short barrel and light weight, pistols generally generate far less bullet velocity than rifles do. There is also the issue of recoil; a heavy or fast bullet will generate more recoil, and the light weight of a handgun means the shooter feels the recoil more.

Handguns are further broken down into two categories, pistols and revolvers. A revolver is a handgun with multiple chambers and one barrel, while a pistol has one chamber per barrel. The term pistol is often used as a synonym for handgun, including revolvers, though the term revolver is never used to refer to a pistol.

Handguns are generally used for two purposes; defense, or to provide more challenge to a recreational shooter. The easy portability of the handgun is what makes it a common choice for defense--even the reduced power and accuracy of a handgun you have when you need it is far better than the power and accuracy of a rifle that you don't have, because it's too heavy and bulky to carry.

Accuracy

Firearm accuracy is a combination of many factors, spread across the three factors of gun, ammunition, and shooter. For top accuracy, all three factors, and their interactions, must be addressed. The primary element in all three is consistency. If everything happens as close to possible the same way every time, then the bullet should strike as close to possible to the same spot every time.

The first factor we'll examine is the gun. The barrel must grip the bullet tightly and consistently, apply the right amount of spin, and release the bullet with minimal disturbance. The sights must consistently align with the barrel from shot to shot. The cartridge must be firmly held in the chamber, so that it cannot shift under the force firing, as this might disturb the bullet as it exits the case or change the pressure in the barrel and thus change the bullet's velocity. The gun must behave consistently under recoil; a loose and shifting barrel, for example, would allow the barrel to shift before the bullet exits, and send it in a slightly different direction each time. Even the vibrations of the barrel can alter the path of the bullet; a long, thin barrel will vibrate more than a short, fat barrel and this will be more prone to spread shots around.

The next factor is the ammunition. The bullet must closely match the bore diameter, so that a good seal is formed; too small and gas will blow by, too large and excessive pressure and bullet deformation will occur. The correct amount of powder must be present, and it must burn at the same rate, so it pushes the bullet down the barrel to the same velocity each shot. The bullet must also sit in the case right; too deep and pressures will go up, too loose and the pressures will go down. The bullet itself must be a consistent weight, and well balanced, with no voids and no damage.

The last factor is the shooter. The shooter needs to have a consistent stance, grip, and pull of the trigger, so that every time the trigger is pulled everything happens in the same way. Much of this is skill, but a good deal of it is also ergonomics of the gun. A light, consistent trigger pull, a comfortable, well fit stock or grips, and good sights all help a shooter control the firing process. A gun that is to be fired without a rest should be light enough to not cause fatigue, but also heavy enough to hold steadily and tame the recoil of the cartridge. An optical sight helps most shooters, as it is easier to focus on the target and reticle when they fall in the same focal plane, and magnification will help shooters with poor eyesight place their shot more accurately. Too much magnification, however, results in a tiny field of view, and high magnification also magnifies the shooter's tremble, which can be distracting.

Accuracy is generally measured in one of two ways; either by the center-to-center measurement of the furthest two shots in a group of shots fired at a given range, or in minutes of arc (MOA). Since one MOA equals about 1.05 inches at 100 yards, it's fairly easy to convert from group size to MOA, though it can be misleading, since a gun that shoots 1 MOA at 50 yards probably won't shoot 1 MOA at 100 yards. Still, MOA is commonly encountered, and a rifle that will shoot 1 MOA at 100 yards is considered to be highly accurate. Some long range hunting and target handguns, like the Remington XP-100 or Thompson-Center Contender, are capable of 1 MOA accuracy, but for the average defensive handgun, a group of several inches at 25 yards is more than acceptable accuracy. The most accurate defensive type pistols, generally found in Bullseye pistolshooting, can group shots in under 2 inches at 50 yards[1].