A Primer on Guns
In preparation for the January symposium on “Guns in America” this post is offered to League readers as a primer of sorts on guns. It is in no way meant to be an exhaustive explanation of guns. Gun laws will likely be covered in symposium posts as well as specifics about what defines an ‘assault rifle’.
Three Basic Gun Types
Rifles – These are often called ‘long guns’ because of their ability to shoot over long distances. Rifles fire one bullet at a time and can come in a variety of sizes and configurations. Rifles have been the prefered weapon of infantry troops for nearly 500 years. Pictured below is the iconic M1 Garand rifle carried by millions of American troops during WWII, Korea and Vietnam.
Shotguns – Although they can also fire single projectiles, shotguns typically fire loads of multiple smaller pellets, known as shot. These also come in a variety of sizes. Below is the Remington 870 which is the best-selling shotgun in history.
Handguns – These are also commonly known as ‘pistols’ and offer hundreds of variations. Handguns fire many of the same caliber bullets used in rifles, though because of their much shorter barrels they have greatly reduced range. Pictured below is another iconic firearm, the Browning 1911.
Caliber vs. Gauge
Caliber – Firearms that use bullets (rifles and handguns) are identified primarily by the caliber of the weapon. Unfortunately in the United States this can be confusing because naming conventions are not standardized. Roughly speaking caliber refers to the internal diameter of the gun’s barrel in inches. So a gun with a .32 inch internal diamter of its barrel will fire a .32 caliber bullet. The smallest bullets commonly used are .17 and the largest are .50. An added point of confusion to the identification system in the United States is the popularity of some metric rounds like the 7mm and 9mm. A good explanation of calibers can be found here.
Gauge – Firearms that use shot (shotguns) are identified by the gauge of the weapon. Gauge is determined from the weight of a solid sphere created from a unit of lead that will fit the bore of the firearm. The size of the sphere represents a fraction of a one-pound unit of lead. For example, a sphere produced from one-twelth of a pound of lead would fit in the barrel of a 12 gauge shotgun.
Bullets – As previously noted, bullets are single projectiles of varying size and used in rifles and handguns. Generally speaking, the larger the caliber, the more power the round has, though factors like distance and intended target play a role. Bullets are nearly always made of lead, sometimes with a metal jacket. Some bullets also have a hollow point which causes the projectile to mushroom upon impact, creating more damage in the target. The bullet is encased inside a cartridge along with gunpowder and an ignition source. Below is a sample of several different cartridges.
Shot – Small lead pellets meant to be fired in groupings are called shot and the size varies depending on the needs of the shooter. The largest shot commonly used is #00 buckshot and this ranges to the smallest commonly used shot at # 7 1/2. There are other less common loads at either end and a complete chart can be found here. Shot is either made of lead or a non-toxic metal like steel or tungsten. The shot is packed into a shotshell along with gunpowder and an ignition source. The diameter of the shotshell relates to the gauge of the shotgun and they can vary in length. Larger shotshells can contain more shot and/or more gunpowder. Below are examples of shot and shotshells.
A firearm action describes the method by which the ammunition is moved and/or readied for firing. This falls into two broad categories. These are manual actions and automatic actions.
Manual actions – These require the shooter to perform a physical action in order to move/ready the round. These can range from cocking the hammer on a revolver to pumping the slide on a shotgun. These are slower to fire and typically carry less rounds.
Single action pistol
Bolt action rifle
Pump action shotgun
Automatic actions – These types of firearms use a mechanical process to do the work of chambering the next round for firing. This process is powered by either inertia from gun recoil or by gas vented off from the firing process. This creates a much faster firing process and these guns typically carry more rounds. There are two sub-categories of automatic actions. Semi-automatic firearms require the trigger to be pulled for each shot. Fully-automatic firearms can fire multiple shots by pulling the trigger only once and holding it down. Some examples of both types of semi-automatic actions below.
Semi-automatic Marlin Model 60
Semi-automatic Benelli M4 shotgun
Capacity in this case refers to how many rounds of ammunition the firearm can hold. This can vary significantly from single-capacity firearms to high-capacity weapons with external magazines. Higher capacity is usually accomplished with either a fixed magazine underneath the barrel or some sort of detachable magazine which is a separate piece of equipment inserted into the firearm to marry the ammunition to the action. The Marlin Model 60 mentioned several times above relies on a fixed tube magazine to provide 14 rounds of ammunition for firing. The AR-15 featured above uses a variety of detachable magazines which can range from 10 rounds to a 100-round magazine produced by several companies. Picture of a 30-round external magazines below.