Physics of a Paintball Gun Barrel

Paintball player
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While the paintball barrel is an important part of a gun, it does not make or break it. Just keep a few things about barrels straight in your mind and you will be able to find what you need.


A typical barrel consists of three major parts: the threading, the barrel shaft, and the porting. The threading consists of the spiral grooves at the end of your gun that allows you to screw your barrel into the gun itself. The barrel shaft is the solid portion of the barrel that the ball will be shot down. The porting is near the end of the barrel where there are holes or openings on the sides of the barrel before the end where the paintball exits.


Different guns have different threads. Just as a screw with big threads will not fit a bolt with small threads, barrels with threads that don't match your gun will not fit into your gun. For example, when you purchase a barrel, make sure that if your gun is a Tippmann you get a Tippmann threaded barrel. There are adapters to go from one threading to another (compare prices), but it is usually better to get the proper threading for your gun, to begin with.


Many people believe that a longer barrel is a more accurate barrel. While this is true to a certain extent, a barrel longer than 12 or 14 inches will actually hurt your gun's performance. The longer a paintball travels down a barrel, the longer it has to straighten out its trajectory, thus traveling more consistently from one shot to the next. The longer a barrel, though, the more air that is required to shoot the ball, making your gun less efficient. In addition to more air required to shoot the ball, a barrel that is longer than 14 inches will actually be so long that a paintball will begin to decelerate before the ball leaves the barrel, causing the ball to travel even shorter distances.


Porting consists of the holes on the sides of a barrel near the tip. These holes serve primarily to reduce the sound of a gun firing by allowing air to gradually escape from the barrel rather than in one load burst at the tip. In general, more porting means a quieter barrel, but more porting also requires more air to fire the ball and decreases gun efficiency. Porting is sometimes spiraled or straight, though the differences are minimal.


Different barrels are in different sizes. While paintballs are supposedly .68 inches in ​diameter different brands of paintballs are different sizes. The key to accuracy is not the length of a barrel but making sure your paint fits your barrel. Ideally, a paintball should be completely round and will not slide down a barrel with the weight of gravity alone, but if you blow on the end of the gun you should be able to force the paintball through. A paintball that rolls down a barrel is too small for that barrel and a ball that requires more than a puff of air from your lungs is too large. Some barrels come in kits (Compare Prices) with multiple attachments to properly match your barrel to any size of paint.


Paintball barrels are made of many materials including steel, aluminum and carbon fiber. The actual material doesn't really affect accuracy, but it will affect weight and lighter barrels typically cost more.