I had a similar prob, I think... make sure you have:

a> CO2 in the tank
b> tank is screwed ALL the way in (my problem)

Other than that I am lost

 

with my older marker...spyder victor...the co2 tank ALWAYS was coming loose... that may be your problem. make sure the co2 bottle is SNUG in the reciever. Don't overtighten it however.

 

Normally CO2 will chill with excessive shots causing a slight dropoff in velocity, but not nearly at the levels you are experiencing. If you have any On/off valves on your gun make sure they are completely open. It definately sounds like you have a bad restriction somewhere in your gas flow to the valve. If running a bottom line try taking it off where it attaches to your marker and blow through it. I'm not sure where the screen is on a Tippmn but that would be worth a check too. Basically just check everything up to the valve for ease of airflow.

 

Your problem is most likely your CO2 tank coming loose a bit. Keep checking it, mine comes loose on my Tippmann all the time. But like they said, dont overtighten it either.

 

what kind of marker you do have? If it has an in-line regulator then that is prolly not worked in. I suggest getting an anti-siphon tube installed- it's only $5 and it keeps all liquid Ci2 out of your marker. Don't forget that the weather WILL affect your Tank's recharge rate- the colder the air, the more time it takes for the Co2 to expand and increase in pressure. When it's hotter out, you will get spikes sometimes(big sparatic jumps in velocity). So, it could just be the weather.
-Petey