What is an Expansion Chamber?

• An expansion chamber is basically just an empty compartment that is attached to the side or bottom of a paintball gun. They can look pretty much like anything, in many cases taking on the look of a gun magazine clip.
  
  

How Does It Work?

• When firing the gun rapidly, the gun can become cold, which affects the ability of the gun to convert CO2 into a gas to propel the paintballs out of the gun. The expansion chamber allows the CO2 in the gun more room to expand into a gas which will keep the gun from getting too cold and allow the shooter more accurate firing.
  
  

Price

• The price of an expansion chamber can vary drastically depending on the size and design, but the average price in 2010 is around $40 per chamber.
  
  

Do You Need an Expansion Chamber?

• Adding an expansion chamber will help drastically for anyone who shoots paintballs at a rapid pace. However, even the addition of an expansion chamber will not completely solve the problem of erratic firing due to the CO2 converting from a liquid to a gas. To further help the problem, many paintball experts recommend adding a regulator device to the gun.
  
  

Regulator vs. Expansion Pack

• A regulator works directly on the CO2 cartridge of the gun, regulating the output of the CO2 into the gun. As such, it is a more direct solution to the problem of CO2 converting from a liquid into a gas than an expansion chamber. While more expensive (an average price of about $80) regulators have been known to solve the problem of CO2 conversion better than expansion chambers.