Major problems

I recently purchased a second-hand tippmann A5. Disensemblied it an it all looked fine. All parts are there, they are clean and intact. But when trying to fire the marker (equiped with the e-grip) it goes wild. When trying to fire one round, the marker fires of the ball but also aditional empty gas-shots. It is like having no control over it, does more or less what it wants. Also suffered major ball breaks in the barrel and in the cyclone feeder. I have no experience of paintball markers and can't figure out whats wrong. When firing the marker without paintballs it seems to work fine, cyclone feeder moves accordingly to number of rounds set on the e-grip. Any suggestions to what's wrong. Can I repair or adjust on my own or should I turn to Tippmann Inc. ?  

thanks,

Andy from Sweden 

Tippmann usually just fixes, with no particular charge.

But - do you have a regular grip?  This could be a problem with the E-Grip or with the hammer/valve.  If you could put a regular grip on there you could see if it is the E-Grip or not.