A typical paintball marker with a plastic hopper on top.
Paintball is a popular outdoor sport that uses paintball markers as the main piece of equipment. Paintball guns use a system of compressed air, nitrogen, or CO2 to push the paintballs through the gun and into the barrel. There are pump action, semiautomatic, and fully automatic paintball guns, but the general process of manufacture remains the same throughout.
There are two main components to a paintball gun–the barrel and the trigger mechanism. The trigger consists of a bolt and valves to control air or gas flow. The barrel attaches to the paintball gun body and is usually threaded. These are usually made out of aluminum, with plastic used for enhancements such as military sim looks. The other components are not part of the main paintball marker package, and are bought separately–the gas system and the hopper.
The markers are made in their separate parts on specialty manufacturing machines and fabricators, and then the parts are put together to form the full paintball marker.
The paintball body sticks with one material, but the barrels can be found with many different materials. In addition to aluminum, you’ll find ceramic and stainless steel. Barrels can be one piece or two pieces. The two piece sets allow you to put different diameter inserts into the main barrel. This allows you to match the barrel to the specific paint that you are using. Barrels are often milled, and the latest barrels can screw in to the body. Older barrels use a slide-in system that is not quite as secure.
The triggers are made out of aluminum, and connects in to the bolt system. When you pull the trigger on a paintball gun, gas is released from your tank. At the same time a paintball is dropped from the hopper into the body of the gun, and is then propelled at high speed out through the barrel.
The entire firing mechanism of the paintball gun is considered the bolt and valve system. There are closed and open bolt systems which function in slightly different ways, but end up with approximately the same level of performance. The valve is the part that controls when the gun fires, while the bolt is what controls both the air flow of either gas or oxygen, along with the balls.
The main area that paintball markers differ is whether they are mechanical or electro-pneumatic. Mechanical markers do not have any computer boards handling ball feeding, rate of fire, or gas propulsion. Instead they use a spring and hammer which provides all of the input for the firing mechanism. Mechanical markers are the less expensive of the two types, and are also easier to manufacture due to not having computer circuits.
Many modern paintball markers are electro-pneumatic. This is a paintball gun that has a computer board that controls the firing mechanism and the ball feeding. The additional steps required to make the board raise the price of the marker. The construction ends up being lighter weight than the mechanical markers. The rate of fire also tends to be much higher. One major advantage is that not as many balls break when going through the marker, since the feed rate is controlled by the chip.