I have air leaking from my velocity screw on my X valve

[Looney712]

I have a brand new x valve and whenever I turn the velocity up around 250 it starts leaking out the velocity screw. I would like to get it around 285-300. Everythings been lubed and the gun shoots great other than the darn leaking. I am using the stock spring if that makes a differance. Any suggestions would be great
thanks

[Gadget]

Sounds like either your reg-piston o-ring is the problem (try oiling it and if that doesn't work, try replacing it) or you've got a faulty reg piston.

[Looney712]

That's what I was afraid of...... Thanks