If you’re going to own and shoot guns, you should know the basic parts of a handgun and how they operate. Understanding the operation of a pistol will help you diagnose malfunctions, maintain your firearm, and communicate intelligently about your gun. The 3 basic parts of a handgun are the frame, barrel, and action. However, each part may contain one or more smaller pieces and parts.

Additionally, one part can have multiple labels to define a different section of the part. By the end of the article you should have a thorough understanding of the name, function, and location of common pieces on both types of handguns (semi-autos and revolvers).

Regardless of whether your handgun is a semi-auto or revolver, the basic parts — frame, barrel, and action — are the same. The frame is essentially the body of the firearm and houses the various parts that make the gun operate. Next, the barrel is the metal tube that a bullet travels down once fired. Finally, the action represents the moving parts that control the cycle of operation.

Although the parts are the same, they look and operate differently on a revolver when compared to a semi-auto. Don’t worry I’ll cover that in more detail below.

Labeled Parts Of A Handgun

Images labeling the basic parts of each handgun by type are below. First, I’ve labeled internal and externally visible parts for a semi-auto handgun. Additionally, I’ve provided the list of parts on a single action revolver. Finally, I note the parts and differences of a double action revolver.

If you are unfamiliar with the labels, don’t worry. I cover each of them in the sections that follow. However, I wanted to provide a visual aid for learning the handgun parts.

Parts of A Semi-Auto (a.k.a. Autoloader a.k.a. Automatic)

parts of a semi-auto handgun labeled
basic internal parts of a semi-auto handgun

Parts of A Single Action Revolver

single action revolver parts
loading gate on a single action revolver

Parts Of A Double Action Revolver

parts of a double action revolver
da revolver with cylinder and ejector on display

Dissecting The Frame

The most notable part of the handgun frame is the grip, or the part where you hold the handgun. Furthermore, two sections comprise the grip; the front strap and back strap.

First, the front part of the grip is called the front strap. Your index through pinky finger grip the front strap. Second, your thumb wraps around the grip on the back strap. Some handgun models have interchangeable back straps to allow shooters to modify the grip to their liking.

Another part of the frame is the trigger guard, and is usually a circular or rectangular outline where the trigger will actually protrude through the frame. Although most firearms have a trigger guard, not all firearms do.

Parts Of The Barrel

parts of barrel: bore with rifling (lands and grooves)

Similar to the frame, the barrel is pretty straightforward. However, there are several terms to describe the features of a barrel. The bore is the inside of the barrel.

The bore of the barrel contains the rifling. Rifling is the blanket term for the raised and lowered areas that run the length of the barrel. Lands are the raised portions of the rifling. Alternatively grooves are the lowered sections of rifling inside the bore.

Additionally, the rifling runs in a spiral pattern to put rotational spin on the bullet. This spin aids in a straight flight pattern and maximum bullet travel distance.

An easy way to remember the difference between lands and grooves is that the part that stick up (lands) are like “is-lands” which stick up out of the water.

Another important term when discussing the barrel is the muzzle. The muzzle is the front-most part of the barrel and is where the bullet actually exits when a cartridge is fired.

Definition & Basic Parts Of The Action

Finally, the most complex part of the handgun is the action. Various different parts make up the action including the trigger, hammer, slide/wheel, and more. A good way to define the action is any part of the handgun that moves during the normal cycle of operation.

Each handgun is different, so some portions of the action will not be present on every handgun. Below is a list of common parts often associated with the action. You can view the locations and/or visual representation of these in the labeled parts section above.

  • Trigger – Initiates the firing of a cartridge by releasing the hammer or activating the striker/firing pin.
  • Hammer – Can be found on semi-auto and revolvers. Has an integrated firing pin or strikes the firing pin to discharge a round
  • Firing Pin – Part of the handgun that actually strikes the primer on a cartridge. May be integrated into the hammer on some handguns.
  • Slide – Found on semi-auto pistols only. Moves laterally when a round is discharged and initiates the unloading/loading of a new cartridge.
  • Recoil Spring – Found on semi-autos only. Transfers energy into the slide allowing it to move laterally.
  • Guide Rod – Similar to the recoil spring, this is found on semi auto pistols only. Keeps the movement of the recoil spring/slide on plane and limits range of the recoil spring.
  • Extractor – Found on semi-auto pistols only. Extracts the spent casing from the chamber allowing a new cartridge to be loaded.

If you are unfamiliar with any of the terms in the above definitions, I highly recommend reviewing the concealed carry test article. Each term is clearly defined there. Additionally, it may provide further clarification on the parts of a handgun with additional graphics and definitions.

So, What Holds The Bullets?

cylinder on a single action revolver removed from the frame

Usually when people ask about “bullets” they’re actually referring to the cartridges. And you’ll notice I didn’t really speak about that in great detail above. That’s because where the bullets are held varies by type of pistol.

On a semi-auto handgun the magazine holds the bullets — or more precisely, the cartridges. Whereas, on a revolver ammunition is housed in separate chambers within the cylinder. In order to clarify, let’s cover the parts of a handgun associated with loading and unloading.

  • Chamber – Can only hold one round of ammunition at a time that is set to be fired. Integrated into the rear of the barrel on semi-auto handguns.
  • Cylinder a.k.a. The Wheel – A rotating cylinder containing individual chambers and found exclusively on revolvers.
  • Magazine – Found on semi-auto handguns only. Holds excess ammunition.
  • Magazine Well – Usually integrated into the grip/frame on a semi-auto. Holds the magazine in place.
  • Magazine Release – Allows for the magazine to be removed from the magazine well.
  • Cylinder Latch – Found on revolvers with a swing away cylinder. Releases the wheel to allow for loading and unloading of chambers.
  • Ejector Rod – Unique to revolvers. This part ejects the spent casings and/or cartridges individually on a single action only revolver OR en masse when pressed while the gun is out of battery on double/single action revolvers.
  • Loading Gate – Found exclusively on single-action revolvers (see above image). Used to load/unload one chamber at a time.

I highly recommend reviewing my concealed carry test preparation article if any of the terms used in the definition are confusing.

Parting Shots

Ultimately, trying to label every part on a handgun is extremely difficult because of variations on makes and models. However, hopefully this article has satisfied your curiosity about the basic parts of a handgun. I’ve tried to be thorough, but if you still have questions feel free to leave a comment. Alternatively, if you found this information insightful, please share with your network.