Personally I would run a Pamler's Stabilizer over an expansion chamber. The main issue with CO2 is the velocity spikes due to the unstable nature of the gas. With unregulated CO2 you could get 500 PSI off a cold just filled tank or 1,000 PSI off a full tank that has been sitting in the sun all day. By using a regulator such as the Stabilizer the pressure going into the marker won't be higher than what you set it at. That helps controls velocity spikes and makes for more consistent shots.

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I would just save my money and get an HPA tank instead of getting an expansion chamber or Palmers Stabilizer. It will be a lot better for you in the long run. You could even find one used on the forums for a good price

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Running CO2? then yes its a good idea.

HPA? Dont bother... you would be better off using the money for another upgrade to the marker

i had one. and i always had issues with it so i dont use it anymore

Issues with a chamber, how'd that happen?? Its just a large tube with dividers in it.

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