New barrel doesnt work on 98C

I recently bought a 14 inch 32 degrees nightstik.  at first my gun fired normaly but after the first game the gun would uncock itself (as if it were out of air) every time i shot.  when i put the factory barrel back on the stock it shot just fine (i didnt refill the air or modify it at all).  does anyone know why this is happening or if your having the same problem?  please let me know, thanks!

clownshooter wrote: Is the front bolt getting stuck in the end of the barrel? Is it the correct barrel for your 98C (Tippmann changed the barrel threads for the 98C after a particular serial number) Do a search on new style 98C barrels. I think there was a thread that listed the 98C serial number where the barrel was changed.

There is another way, check wit the local pbshop, they would know off hand if the 98c has the old threads or not...Im always being asked by the salesman about this when I purchase a new barrel for my 98c.