rapid fireing

Welcome to the forum.

We are going to need some more details to help.

Type of gun, type of upgrades, age of gun, other problems, circumstances, etc.

Need.more.data.

Lets try from the top here.

If you screw in the tank, cock it and pull the trigger once, does it keep firing until the tank is empty? You might have a bad sear/sear spring. Not too expensive to fix.

Or do you mean that it works ok, but here and there it fires multiple times? You might have a bad spring in your trigger, or are pulling back too far and stopping the sear from engaging again.

After sitting around for a few years it likely needs a new set of springs entirely. Look into the Madman spring set.

this has happened to me a few times. 

when my tank froze before i had a expansion chamber it rapidly fired.

when my hopper could'nt keep up with my shots it rapidly shot Co2 untill a ball dropped in.

and finally when im almost out of air.  but you said its full on air.

like mentioned above check the springs, sear pin, bolt. but if it does it again check if the tank is frozen or if the hopper is feeding.   those were the causes of my problems.

 

Ive never heard of a problem like this but like said above cheack the sear pin, bolts, the feeding mechanism, and springs. i have an X-7 so i don:t need to worry about ball feeding.

Is this happening ALL the time or occasionally?

Have you lubed it up since you received it? If it has been sitting for years than it wouldnt hurt to send some oil through it.
If you have some trouble picking up a spring kit and will have to order one online but looking forward to playing now; I had the same problem on a weekend retreat at a inlaws house in the sticks and I just needed a quick fix to hold me over another day. I removed my sear spring and while holding each end streched it out alittle, then replaced it with no further problem until I (purchased a new spring kit).

I would only recommend this as a temp fix.

Have you ever disassembled a tippmann 98 custom before?

Sears and hammers should last for tens of thousands of rounds. Tippmann had a problem with a batch (apparently a big batch) of parts that was not hardened and tempered properly. Some wore down too soon and some chipped. Contact Tippmann and explain the problem. They will likely replace the parts free of charge. Go directly to Tippmann as some of these bad parts appear to have made it into the system so that new replacement parts from some of the vendors suffer the same defect.

Thanks for your input guys.

I since stipped my 98 checked the sear spring and that seems fine but I'll brobably replace it anyway.

I found a little chunk missing on the hammer "o" ring do you think this would make any difference in performance or could this contribute to my problem of rapid firing, as it would be leaking blow back air to reset the hammer?

What do you think?