How Does a Paintball Gun Work?

Paintball guns are something of a mystery to those who’ve never used one, but the way that they work is actually quite simple at the end of the day.

We’re going to explore the various types of paintball guns and explain how they function, which will allow you to be more intimately familiar with the function that underlies the form of your marker.

Gregory, Author Paintimpact
How Does a Paintball Gun Work?

The Basics

Paintballs are expelled from the end of the barrel by a short and controlled burst of gas, generally released from a canister of carbon dioxide held within the gun but in some cases nitrogen gas or even regular air can be used depending on the type of gun you’ve got in your hands.

The paintballs are fed in front of the firing assembly by the hopper, ideally keeping a single ball in place until the next pull of the trigger. The hopper places the ammunition directly in front of a piston which is powered by air, springing forward and flinging the ball at speed in the direction the marker is aimed.

The firing assembly will vary from gun to gun, but in general it will consist of a gas valve which is sealed against the constant release of the gas of choice and allows the bolt to move forward.

The trigger itself releases the sear, a small piece which holds everything in place against the pressure from the canister and causes the firing assembly to move forward as the gas is released. This pushes the ball out at speed, and what happens next will depend on the type of gun that’s being used.

Paintballs are fired at relatively low speeds, most fields limit guns to about three hundred feet per second. This speed can leave a bruise or welt at close distances but it’s unlikely to cause any serious harm at a distance greater than ten feet or so, especially if the person being hit is wearing appropriate gear.

That said, eye and ear injuries can, and will, occur if you’re not wearing a mask and some form of ear protection. Most fields won’t let you play without one anyways, but even if you’re the modern day incarnation of Rambo keep your mask on if you’re just playing with friends somewhere without safety rules in place.

Pump Action Guns

Pump action markers used to be the absolute rule, but they’re becoming less and less common on the field itself although some still favor them. There are also tournaments which will only allow you to use a pump action, and for some elder paintballers it has the ill-defined allure of nostalgia.

These markers are single fire, you’ll have to work the pump between each shot as there’s no mechanism which resets the bolt after the ball has been fired. This makes for a much lower rate of fire than many modern guns, but with less moving parts they tend to be the most reliable markers around.

Semi-Automatic Guns

Undoubtedly the most common on modern fields the world over, semi-automatic guns work in a similar way to firearms in the same class. The spring will reset between each shot without any more involvement from the shooter, putting the rate of fire at a respectable rate of… as fast as you can pull the trigger.

They work by diverting the gas to the front of the firing assembly, pushing everything back into place as soon as the next shot is going to be fired. Almost any entry-level paintball gun is going to be in this class, and they’re generally able to be used without restriction on most fields.

If you’re just getting into the sport, this is exactly what you’re looking for.

Ramping Guns

Ramping is one mode of fire that really doesn’t have an equivalent in real firearms. In this mode the gun will have a set level of fire at which the gun will begin to assist the bolt with an electric motor. It’s a complex process, requiring a bit more gear than your usual markers, but it leads to an impressive result.

The gun will begin to fire more and more quickly once you reach the point where the motor kicks in. The rate of fire will increase as you pull the trigger until you’re firing a dozen or more paintballs per second while maintaining the same amount of trigger pulls.

Check with your field or tournament before you use one, however, as they are sometimes banned due to the possibly excessive rate of fire.

Automatic Paintball Guns

Pull the trigger, hold, spray down the field with paint. Essentially an automatic paintball gun will allow you to fire multiple shots with a single trigger press. They function using a circuit board which regulates the firing assembly and basically “turn on” when you pull the trigger.

They often feature a motorized hopper, since a gravity-fed hopper can really only feed about eight balls a second or so and who wants to limit their rate of fire to something sane?

If you’re playing with friends, they can be a great way to ruin someone’s day, which might be desirable depending on how you like to play but they’re generally banned on most fields and in tournaments.


Since they have a lot of parts moving at high speeds, some level of maintenance is required for paintball guns in regular use although not as much as you’d think.

Don’t overdo it, you’re more likely to have a problem by improperly reassembling the gun than you are from any kind of wear.

For the most part, you can find paintball gun oil and use that to keep things lubricated when you do decide to take it apart. The wrong oil will destroy your seal. Use something which is made for markers, or you risk the gun itself failing.

Other than that, try not to drop it in the mud or bang it against anything too hard and make sure to clean the barrel after each game and you should be good to go.


Paintball guns are a lot more fascinating if you know how they work, and while each model is a little bit different the general rules are the same between equivalent gun types. A little bit of understanding is the key, and once you’re intimately familiar with your marker you’ll develop a healthy level of respect for the intricate inner workings that allow you to shoot your friends in the face without killing them.