Gun Anatomy: The Inner Workings of a Firearm
Every survivalist or prepper should plan to have a means to defend themselves – and in most disaster scenarios, that means you need a weapon. If you are equipped to survive in the case of a catastrophic event, whether it’s the breakdown of society, a natural disaster, or any other terrifying alternative, chances are you have a weapon or are looking to get one. This is critical for protecting yourself and your family in case of disaster.
If you’re going to be the owner of a firearm, it’s important to understand how guns work. Understanding the different parts of a gun and what their functions are will allow you to take better care of your weapon, and will also help you to better understand how to handle firearms safely.
Today we are going to take a look at the three of the most common types of weapons – handguns, shotguns, and rifles. These are the three primary types of guns that are widely and easily available to the public in the USA. Having good grasp of the gun anatomy of these three types of firearms will allow you to take better care of your firearms and might even help you avoid or resolve common malfunctions that gun owners sometimes experience.
Before I go on, it is important that you have at least some basic training in firing a weapon before you purchase one. I wouldn’t recommend driving a car without at least taking a driving lesson, and I would not recommend purchasing a firearm of any sort without at least learning how to properly care for and use one.
Gun Anatomy 101: The Universal Parts of a Gun
All firearms come with three main groups of parts. Each weapon has an action, a stock, and a barrel. These are universal truths. The action is the internal part of the weapon. Inside the action you will find all the moving parts that are used to load, shoot, and eject either shells or cartridges.
The stock is the rear part of the gun, comprised of the butt and the fore-end. In a handgun, the stock would be considered the handle. If you picture a rifle, the butt is the part that you would brace against your shoulder when aiming.
The barrel of a weapon is the metal tube that discharges the projectile. The barrel will have been bored-out to accommodate a particular type of projectile. When the projectile is fired, it shoots down the barrel and is ejected out of the muzzle. Different barrels have different effects on the rounds they fire – smooth barrels are smooth on the inside. Rifled barrels (unsurprisingly frequently found in rifles) have a grooved inside that causes the bullet to spin when it exits the barrel. This essentially makes the bullet fly straighter and can therefore make guns with rifled barrels more accurate. This follows the same principle as why you want spin on the ball when you throw a football – it makes the “flight path” more accurate.
The Various Categories of Guns
Every gun is different. There are hundreds of models of guns and dozens of different categories. Even when looking at a rifle, there are many different types of rifles. You have a bolt-action rifle, a lever-action rifle, and a semi-automatic rifle. The type of rifle is determined by the action and how the gun works. Each one comes with strengths and weaknesses, while some are ideal for hunting and some are ideal for precision shooting or self defense (if you’re interested in learning more about options outside of firearms, we have a list of the best self defense weapons that are non lethal)
The same can be said for handguns and shotguns. There are almost countless different types. To make all this much simpler for you, the rest of the article will be broken into three sections describing the complex anatomy of each class of weapon, plus the different sub-types that exist within the broader class of weapon.
First, let’s look at rifles.
Anatomy of a Rifle
The Different Parts of a Rifle
The main difference between rifles is the type of action used. Every rifle will have a butt, which is the end of the rifle that you rest against your shoulder while firing, and every rifle will have a barrel. The big difference between weapons is with the action, which is comprised of the following parts:
Fire Control Group: The fire control group includes the disconnector, the seer, the trigger, and the hammer. These are the parts that are used to fire the weapon.
Trigger: The trigger is the lever you pull to fire the weapon, setting off a chain of events that result in the bullet shooting out of the muzzle.
Hammer: The hammer contacts the primer area and causes the powder to ignite, which then launches the bullet out of the muzzle. You don’t generally see these on a rifle, as they are hidden inside the action.
Receiver: The receiver is the body of the action. This holds all the pieces together and attaches the barrel to the furniture and the magazine.
Bolt: The bolt holds the firing pin and supports the rear of the cartridge, and also seals the cartridge inside of the firing chamber.
Bolt Handle: The bolt handle is what controls the bolt. It is used to load or unload a rifle.
Safety: The safety is what keeps your rifle from accidentally firing. This can come in the form of a button, a sliding component, or a switch. It is generally located next to the trigger. The safety works by blocking the trigger mechanism so that you can only fire the weapon when the safety is unlocked.
Breech: The breech is the part of the gun where you load ammunition.
Not every rifle comes equipped with the same parts. For example, break-action rifles don’t have bolts, but bolt-action rifles definitely do. Let’s take a look at the most common types of rifles.
The Different Types of Rifles
Manual Action Rifles
Manual-action rifles require you to do more work. You must manually load the next round before you can fire. The only thing that happens when you pull the trigger on a manual rifle is that it hits the hammer or the striker to fire the bullet. You must do all the reloading yourself.
Break-action rifles are single-shot action with a hinge inside of their receiver. When they are unlocked, the barrel will pivot down and eject the used cartridge, then you can load a new one. Break-action rifles are lightweight and maneuverable, but they can be super slow to reload. You need to move the whole gun just to load another cartridge, and so you can’t aim continuously while firing the weapon.
These are the most popular types of rifle. You often see these in TV shows and in the movies. These rifles come with a metal receiver locked onto the barrel and surrounding the bolt. The bolt handle is lifted and pulled back to open the breech, where you can then load your bullet. When the bullet is loaded and the handle is pushed forward, the round is then chambered and ready to fire.
This takes a bit of practice, but once you know what you’re doing, you can easily and quickly fire this weapon repeatedly without losing your target. These rifles come both in single-shot varieties and with magazines. You can fire multiple rounds before needing to reload, and there are many available types of ammunition.
These rifles are popular because of their rigidity and their pinpoint accuracy. These are also very good learning rifles for young shooters. For hunting, for long-range shooting, and for just about any survival situation, a bolt-action rifle is useful. These are also ambidextrous, so you don’t have to worry about your right or left hand.
Lever action rifles are straight out of the Wild West. With these weapons, you must move the lever down to load a round from the magazine, then pull the lever up to load the round into the chamber. It is actually really simple, and it is definitely quicker than using a bolt-action rifle. When you pump the lever, your finger ends up right back on the trigger, and so you can continue shooting without interruption.
The only downside to these types of rifles is that they have extremely small magazines and they are not that rigid. Plus, it’s hard to shoot from a bench because of the lever. However, they are great for shooting short distances, and especially for hunting.
While dramatically less popular than other rifles, the pump-action rifle is actually the quickest. All you need to do is pump the forend backward and then forward to reload. You can use tubular magazines with large capacities, you can fire quickly, and you can count on the dependability of their mechanisms. However, these are not great long-distance shooters.
Automatic rifles, also known as autoloading rifles, can be either fully automatic or semi-automatic. Semi-automatic rifles fire a single shot at a time, since the hammer is prevented from striking the primer the moment a new round is chambered. Fully automatic rifles will continue firing so long as the trigger is pulled. The hammer will continue striking as each new round is chambered. Think of it like holding the trigger on a jackhammer. So long as the trigger is held, the hammer continues to pump.
Then there are select-fire rifles, where you can choose between fully automatic and semi-automatic. You can also choose to fire in burst mode, which will count a handful of cycles before the disconnector stops the hammer from striking the primer. The disconnector is a small component which prevents the hammer from hitting the primer.
Blowback rifles are semi-automatic. They work because the recoil from your shot pushes the bolt backwards just enough so that the old round is ejected and the new round is loaded. The preferred ammunition for these types of rifles is .22, and heavier ammunition is not recommended.
These types of rifles are gas operated. They use the energy from the expanding gas propelling the fired bullet forward to cycle the bolt backwards and eject the old round. A spring is then implemented to push the bolt forward, thereby loading the new round. These rifles use a piston to push against the bolt.
These are super reliable rifles but heavy with recoil. This means they are not as accurate as many other types of rifles. They are not necessarily inaccurate, but the recoil can make them less accurate, especially with amateur shooters.
These are the most popular types of rifles. The M16 and the AR15 are both direct impingement rifles, and they use gas rather than a piston to act upon the bolt. This direct impingement reduces the amount of moving mass, which equals less recoil and better accuracy.
Short Action VS Long Action
These are two terms that can be confusing to new gun owners. In essence, a short-action rifle refers to a certain size of receiver, specifically receivers that are .308, while a long-action rifle refers to a receiver that is sized .30-06. All this means is that a long receiver is longer. Everything about the gun is the same except for the receiver. But this is not generally something you will need to worry about.
Anatomy of a Handgun
When talking about handguns today, we are going to be talking about a modern handgun the semiautomatic pistol. We’re not talking about a flintlock pistol or an old six-shooter revolver with a cylinder. These are modern weapons with modern parts. And while there are loads of different kinds of modern handguns, they all work reasonably similarly. Here is a breakdown of every important handgun part.
The Different Parts of a Handgun
Barrel: The barrel is the end of the handgun where the bullet travels through to be expelled from the muzzle. Barrels are rifled on the interior so that the projectile can rotate during its exit, giving it the stability and accuracy needed to hit your target.
Forward Sight: The forward site is used to align the front part of the weapon with the rear part. This is what helps you aim, lining the rear sighting device perfectly so that you can get the best shot.
Rear Sight: This is used for aiming. The rear sight is generally more important than the front sight (on most models of handguns) and is used to align the gun with the front sight and therefore direct the muzzle at your target.
Ejection port: This is where the cartridge is going to be extracted from. The ejection port is a cutout on the middle section of the slide, where the used cartridge will be ejected out from. You can use this area to check the firing chamber.
Slide: The slide is the assembly which houses the upper section of the handgun. The slide will contain a ribbed platform which you pull back to manually load the weapon. This only needs to be done for the first shot, as the slide will automatically pull back with the recoil of a fired shot to load a fresh cartridge into the firing chamber.
Slide Lock: The slide lock is just a locking device to keep the slide in its rear position, ensuring the chamber remains empty. When the final cartridge of the magazine has been fired, any semi-automatic handgun will engage the slide lock automatically to keep the chamber open.
Grip: The grip is the handle of the weapon. You want to use two hands on the grip when firing, one hand around the grip and the other hand around the grip and your strong hand.
Magazine Well: This is where the magazine goes, and it is positioned at the bottom of the grip. It is grooved to allow the magazine to directly fit inside of it.
Magazine Release Button: This is the button which ejects the magazine from the grip of the weapon. It is located behind the trigger and above the grip, generally.
Trigger: The trigger is the lever that fires the weapon. It causes the hammer to strike the primer and set off the whole chain of reactions. Double-action triggers will cock the hammer or striker and release it in one smooth motion, whereas with an older handgun you must first cock the hammer.
Trigger Guard: This is the ring around the trigger lever itself, used to protect the trigger from accidentally being pulled when inside a holster.
Take-Down Lever: This is the lever used to breakdown the weapon into its major components, which you only need to use when it is time to do some cleaning or maintenance.
Magazine: Magazines are fed into the magazine well, and as you fire the weapon each cartridge inside the magazine is fed into the firing chamber. Magazines rely on a spring-loaded assist to continuously push the next fresh cartridge into the chamber.
There are many different types of magazines, including extended magazines, single-stack magazines, and double-stack magazines.
Accessories Rail: This is the rail on the top part of the handgun with which you can attach tactical accessories. Most handguns allow you to attach lasers for aiming, flashlights, small scopes, and much more.
Tang: The tang is the small overhang that rests above your firing hand. The tang is used to help you handle the recoil of the handgun. It also protects your hand from the slide assembly as it is in motion. Without the tang, you could pinch your hand in the assembly as it moves.
Muzzle: The muzzle is the final part of the handgun. This is where the bullet touches as it is fired from the weapon. Many barrels have a threaded muzzle so that you can attach an accessory like a silencer or a suppressor.
Handguns can broadly be broken down into three types (there are more than that, but these three are by far the most common).
The Different Types of Handguns
Single Action Revolver
A revolver is a handgun that has a rotating (or revolving, hence the name) cylinder in the body of the gun that contains multiple chambers. Each of these chambers holds a single round. A single action revolver is any revolver where the hammer needs to be cocked (pulled back) after each shot is fired. A single action revolver is what you’d imagine if you think of a handgun from the old west – the kind that a cowboy might use. Imagine back to an old Western film where the main character does the “fanning” quick trigger motion to take out multiple adversaries – the reason why that motion is necessary is because the hammer needs to be pulled back after each shot. Most revolvers, both single and double action, hold 6 or 7 rounds. The most common single action revolver, both in terms of circulation and in terms of general recognition is probably the classic Colt Single Action Army (or Colt SAA). Single actions are referred to as such because pulling the trigger only does one thing – it fires the gun.
Double Action Revolver
A double action revolver is any revolver where pulling the trigger does two things – it first cocks the hammer back, then fires the round – hence the term double action. The mechanism with the cylinder that contains multiple chambers is the same in both single and double action revolvers. Most double action revolvers can also be used in the way that single actions are used – meaning that you can choose to cock the hammer back if you want to. However, double actions can also be fired when the hammer is uncocked. One advantage of the double action is that you can draw-and-fire without worrying about the hammer, which also means if you need to be ready to fire, you don’t need to carry around a cocked weapon. The drawback is that the trigger mechanism is harder to pull (it has more resistance) in double action revolvers. However many people feel that the higher resistance trigger leads to improved safety – misfires are less likely.
Semi Automatic Pistol
A semi automatic pistol is what you probably imagine when you think of any “modern” handgun. Unlike revolvers, pistols only contain a single chamber, and instead of the revolving mechanism, a pistol has a magazine that detaches from the grip of the handgun. This is where cartridges (bullets) can be loaded. Semi automatics are referred to as such because the act of pulling the trigger not only fires the gun, it also moves the next cartridge up into the chamber and primes it to be fired. It also ejects the spent casing from the gun.
A semi automatic pistol will fire once every time you pull the trigger – no other action is needed. Semi automatics are more “space efficient” than revolvers (they only have one chamber), and as such they typically can hold significantly more ammunition – some semi automatic pistols can hold up to 20 rounds. Most law enforcement in the US these use semi automatic pistols as their “primary” handgun.
Other types of handguns include single shot and break action handguns, which we won’t cover here because they are relatively uncommon.
Anatomy of a Shotgun
There is a lot to know about shotguns. These are long guns that fire shells, as opposed to rifles or handguns that fire bullets. The major difference between shotguns and rifles is that shotguns have smooth internal barrels and rifles have spiraled grooves machined on the interior of their barrels. The smoothness of the shotgun barrel allows it to fire various sizes of pellets – allowing a wider variety of ammo and therefore a higher level of ‘improvisation’ in what you can shoot.
The flip side of this flexibility is that shotguns are not nearly as accurate as rifles because they lack the rifled barrels and therefore the spin. There are some shotguns that have rifled barrels – but they aren’t all that common and are really just a kind of “hybrid” weapon. Smooth barreled shotguns offer a larger spread and better damage at close range, which is why they are preferred for activities like duck hunting.
Let’s break down all the major parts that come with a shotgun.
The Different Parts of a Shotgun
Barrel: The barrel is the end of the shotgun, and the size of your barrel depends on the gauge of the gun, if it is 12-bore or 20-bore.
Muzzle: The end of the barrel where the projectile fires out of.
Bore: The hollow part inside of your barrel is known as the bore. Almost every shotgun comes with a smooth bore, but more advanced modern weapons can come with a rifled barrel. These types of shotguns will accept sabot slugs.
The bore diameter determines the gauge of your shotgun. Keep in mind that smaller gauges mean a wider bore. The gauge is determined by taking a single lead ball, which fits perfectly inside the barrel, and then finding out how many balls would make a pound. So, it takes twelve lead balls that are the exact fit for a 12-gauge shotgun to reach a pound.
Choke: The choke is located on your shotgun’s muzzle. It is used to control the constriction of your shot in the same way a nozzle of your garden hose controls the flow of water.
Magazine: This is the same as with rifles and handguns. A shotgun magazine is usually a small tube that goes beneath the barrel. You may also find a box-type magazine which snaps into the receiver itself.
Forend: This is the shotgun pump. It slides back to eject a used shell and to cock (prepare) the action. When it slides forward, a new shell has gone from the magazine into the firing chamber.
Action: The action is the area of the shotgun responsible for loading, firing, and unloading. There are several different types of actions for shotguns: pump-action, semi-automatic, bolt-action, and break-action.
Chamber: This is the chamber that holds the shell. It can be on the side or on the top of the shotgun.
Bolt: The bolt is what blocks the breech and moves back and forth to physically load and unload shells.
Receiver: The receiver houses all the parts of the action and trigger mechanism. It has special threading for you to attach external accessories.
Trigger + Trigger Guard: Same as all other weapons, the trigger is pulled to fire the weapon and the trigger guard surrounds the trigger, mainly for safety reasons.
Safety: The safety on a shotgun is used to block the trigger and hammer when not in use. You can generally find the safety in front of the trigger guard.
Stock: Lastly, the stock is the part of the shotgun you rest against your shoulder. This improves your aim and adds structural support to the gun’s mechanism. Most shotgun stocks come with a recoil butt pad to help reduce the recoil when firing.
The Different Types of Shotguns
Other than the types listed below, there are also lever action shotguns (these are old school and aren’t that common) and bolt action shotguns (where they were sometimes used as a replacement for rifles that had been outlawed for certain kinds of hunting).There are also sawed off shotguns, which are shotguns with a shorter than normal barrel – these give up firing range, but are easier to conceal and offer greater portability (some sawed-off shotguns are literally shotguns with a part of the barrel sawed off as a modification).
Break Action Shotgun
Break action shotguns are the “old school” shotguns that you see in westerns (like the shotgun equivalent of the single action revolvers we discussed above). They are the simplest, most primitive kind of shotgun. Break actions have a hinge. Once fired, you need to open the hinge, extract the shell, load a new one, then close the hinge again to take another shot.
As such, the number of shots available to you before you need to reload is capped at one or two at the most. In a dangerous, stressful situation, reloading might be difficult to do quickly. For this reason, break action shotguns aren’t the best choice for self defense or home protection. On the other hand, some enthusiasts, particularly hunters, like break action shotguns because using them encourages a higher level of patience and accuracy. They’re also more “traditional” than many of the sleeker and more modern shotguns produced these days.
Many break action shotguns are double barrel – which means you get two shots rather than one for each reload. Normally there is a right barrel and a left barrel (although sometimes they are top and bottom instead) The mechanism is designed to fire one side first, and then the second. There are even triple barrel shotguns out there. Obviously, there are also single barrel shotguns.
Pump Action Shotgun
Pump action shotguns can hold more than one or two rounds, but each round needs to be loaded into position by “pumping” the shotgun. Imagine any shotgun from a 90s action movie and you’re probably imagining a pump action. Pump actions are also known as slide actions because the pumping motion requires you to slide the action back.
The pump motion both relaxes the used up shell and chambers the next round to be fired. The classic sound that you might associate with a shotgun is probably the sound that these types of guns make when they’re being pumped.
Pump actions remain popular because they are mechanically straightforward, meaning that they have high reliability. That’s why they’re quite popular as a firearm for home protection. They are also frequently used by law enforcement for tactical purposes.
Semi Automatic Shotgun
A semi automatic shotgun is similar to a semi automatic rifle or pistol – upon the trigger pull, the gun fires, the spent shell is ejected, and a new round is chambered. Shots can therefore be fired more quickly than with either of the other two types of shotguns.
The downside of semiautomatics in all cases, including semiautomatic shotguns is that because they’re more complex, they’re more likely to jam or be prone to mechanical issues when compared to pump actions. Maintenance is therefore also significantly more important with semiautomatic shotguns in order to ensure that they work smoothly when needed.
There is so much more to go over when it comes to weapons. This is a simple breakdown of the parts you will encounter as you continue your journey to becoming an effective shooter and a safe weapon owner. All these parts are critical to understanding how your weapon works and how to maintain it. You still need to learn how to fire the weapon, how to maintain the weapon, and so much more.
There are also far more types than described here. You have sniper rifles, machine guns, sub-machine guns, carbines, and lots more. You can explore the various types of firearms as your knowledge progresses. And remember, always stay safe.