98 Custom Power Tube

my tippmann 98 custom has a little bit of a problem.  the velocity screw will not go into the whole, i put it in and it just keeps spinning and spinning. i think the part to fix this is the power tube, am i correct? i was also wondering, without the velocity screw in at all, what is the gun shooting at? High velocity or low?

You say it's just spinning and spinning?  Are the threads catching in the powertube?  Sometimes, the powertube can be just slightly offset in the receiver and not allow the threads on the adjuster to catch.  Try loosening the screws on the receiver that hold the valve/powertube in place, then screw in the velocity adjuster.  Once in, tighten the screws back up on the receiver.

As far as velocity goes, Mack says it has to be chronoed to find out and he is right.


Edited by Hubb - 02 June 2010 at 7:16pm

Hudson wrote: how do you chrono it?

With a chronograph.  Fields (should) have them and you can purchase small handheld ones.  I play mostly outlaw, and I have one of the small ones.  Works great.