Did you know that airguns, in some form or another, have been with us since the 16th century?

They’ve provided a number of uses down the years, but today, they are commonly used for killing rodents and other pests, and recreational target shooting.

But how does an air gun work? What makes them different from standard firearms?

The simple answer is they use compressed gas or air to fire a small, metal projectile, rather than the chemical reaction between the contents of a shell and a bullet.

But there’s more to it than that, so read on as we explore the science behind air guns.

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How Does an Air Rifle Work? Too Long, Didn’t Read

For anyone who might not have the time to read the full article, here’s the brief summary on how airguns work:

Airguns use a variety of different methods for firing a pellet downrange, including a spring-piston, Co2, and compressed air.

man aiming an airgun

And within those methods, there are variants in the ways they operate and fire ammunition.

But for the most part, compressed air or gas is used to actually propel the BBs, contrary to the belief that it’s a piston or spring striking the pellet itself.

What is an Airgun?

An airgun is defined as a pistol or rifle that uses pressurized gasses to fire metal pellets at a target. While many might look and feel similar to firearms, airguns are mechanically powered.

They’re also much cheaper, quieter, and more accessible than real steel – especially in countries where gun ownership is severely restricted, and/or banned.

Airguns have a long history, and the oldest existing example is dated at around 1580.

Here’s a little terminology:

An airgun is also called a BB gun, or pellet gun, and fires metal BBs or pellets (more on this, below).

An airsoft gun is less powerful and is used for safely shooting at human targets. However, the ammo it uses are regularly referred to as BBs – hence the confusion.  Although they are plastic rather than metal.

This article on airsoft vs BB guns explains everything in more depth.

Now that’s cleared up, let’s take a look at airgun working mechanisms, and how each version of the weapon is actually powered.

Each has their own advantages and disadvantages, which we might cover in a future article. But first, as a general guide, check out the video below which breaks down how a basic airgun works.

Airgun Power Sources

The power source of an airgun – the method with which the weapon uses to fire its ammunition – is known as its “powerplant.”

And the following powerplants are the most commonly available in the airgun world, each with a brief explanation on how they basically work.

Spring Powered

Also known as a “springer,” this type of airgun works by pulling back a piston pump, which compresses a coiled metal spring when you manually cock the gun.

When the trigger is pulled, the spring is released, firing the piston forward violently. This forces the air to expel the pellet downrange.

Gas Spring

Some modern airguns use gas (commonly nitrogen) to power an enclosed piston and are typically called gas springs, gas piston, or gas rod airguns.

They work in a similar fashion to the coiled steel spring, but when the gun is cocked this time, gas held in the cylinder becomes more compressed, which then extends a firing rod to push the piston forward when the trigger is pulled and the gas is released.

Pump Pneumatic

Pump pneumatic airguns work by mechanically compressing the air, which is achieved by pumping a cocking lever located somewhere on the body of the gun – usually under the barrel.

Single and variable/multi-pump pneumatic guns are available. The advantage of multi-pump guns is that you can adjust the level of compression – and therefore power – for shooting greater distances.

Precharged Pneumatic (PCP)

Just as their name suggests, precharged pneumatic guns work by using air from an internal reservoir that has been pre-filled from an external source.

When the trigger is pulled, a hammer hits the release valve, and a set amount of air is expelled to propel the pellet from the barrel.

PCP guns are increasing in popularity in the airgun community, as they have several significant advantages over other types of airgun.

This dedicated article on PCP airguns will tell you everything you need to know.

man holding a pcp air rifle

Co2/Compressed Gas

Co2 airguns work by using a pre-filled canister of carbon dioxide, which can be located under the barrel or in the handle of the weapon.

The Co2 canister is then pierced inside the gun, and the gas is stored under pressure, and then released to fire the pellet downrange when the trigger is pulled. They are the only type of “airgun” that is not actually powered by air.

However, while they work in similar ways – and can look almost identical –  Co2 airguns are not to be confused with Co2/green gas airsoft guns.

Airgun Ammunition

Airguns fire small, metal “diablo” style pellets, but many rifles also use metal BBs – spherical ball bearings. These BBs are commonly made out of steel, copper, and/or lead.

The most popular calibers are .177 and .22. Find out which is the best by reading the article found at that link.

Metal BBs might also be anodized, or coated with zinc or other substances to help improve velocity and reduce friction through the shot cycle.

However, airgun BBs are not to be confused with airsoft BBs – which is a different type of ammunition altogether. Follow this link for more information on airsoft ammo.

Likewise, you should never load an airgun BB in an airsoft weapon. Follow that link to find out why.

There are other types of airgun ammunition available, such as darts and arrows – but they’re more commonly used with tranquilizer guns.

Most airguns are breech-loading weapons, which means the ammunition is loaded directly into the bore, at either end, depending on the type of rifle you’re using.

Mag fed airguns are available, but single-shot airguns are by far the most common.

airgun with ammo on table

Airgun Uses

So, armed with all the information above, you should have a fair idea of what airguns are typically used for today – if you don’t already.

For the most part, both air pistols and rifles are primarily used for either target shooting, or rodent and small pest control.

When it comes to the former, airgun events are included in the Olympics, and so competitive airgun shooting is very popular.

“Plinking” is also a lot of fun – recreational shooting, so-called after the sound a pellet can make after hitting bottles or drinks can targets.

You might even have used one to win a large, cuddly teddy at a fairground.

They can also be used for hunting small game, and are very popular for tactical training exercises, considering both the guns and ammo are far more affordable than firearms.

And speaking of tactical, check out this interesting piece that explains what sets tactical gear apart from everything else.


Can an airgun be used for self-defense?

Yes and no. It depends on so many factors – far too numerous to go into here – and it would take up a full article in its own right.

Many airguns can certainly look intimidating, and the more powerful options out there are for sure capable of lethal force.

But if you’re serious about home defense, and you feel there is the possibility of a genuine threat, then a real firearm is arguably the better choice.

An airgun is better than nothing, however, although whether you actually need anything at all is up for debate.

Are airguns painful?

Hell yes. With most good-quality airguns firing well upwards of 500 FPS, you’re going to know about it if you get hit.

Which is why you should always be wearing adequate eye protection, never point or fire at anything you don’t want to injure or kill, and follow the same kind of safety rules and etiquette you would with firearms down the shooting range.

Is owning an airgun illegal?


The laws governing the sale and ownership of airguns might well differ depending on your country, state, and/or region, but at the time of writing in the US, airguns can be bought and owned by any person over the age of 18.

Can you fly with an airgun?

Airguns come under the same rules and regulations as firearms, so while you can fly with one, you need to make sure it’s safely and securely checked-in – and not as part of your carry-on luggage.

This article on flying with firearms will give you more information.

Can you use an airgun for airsoft?

No! Airguns are much more powerful than airsoft guns, and even if you try and use 4.5 mm plastic pellets in an airgun, the FPS is going to be far too high for safe airsoft use.

Plus, you run the risk of pellets breaking inside your gun, and ruining the internals. Keep the metal for airguns, and the plastic for airsoft.

How does a pellet gun work?

The same way an air rifle does – since they’re one and the same thing.


How does an airgun work? It depends on the type of gun. But I hope this article has been informative in some way, and has armed you with the knowledge to make an informed choice – whatever that may be.

Let me know your airgun experience in the comment – which powerplant do you prefer? What do you use your airgun for? What articles would you like to see on the airgun world?

Stay safe out there, and happy shooting!