[lurkingknight]

I have a project p90... I've replaced the trigger/wiring and installed a triggermaster mosfet.

The gearbox is supposed to have an sp120, but is shooting around 360fps. I tried an sp110 and it shoots about 20-30 less. The gun has a 247mm madbull barrel and guarder clear bucking/nub. Cylinder is ported. The spring chart says I should getting 430~ It's not at upgraded so I'm guessing 410-420 would be more accurate. The chart says an sp110 should be around 400. The 110 is currently in my m14 and it's shooting 407-410.

So I'm convinced I've got an airleak somewhere.Though I'm not quite sure how to diagnose it. The funny thing is that I was able to get another 15-20fps by rotating the port to the top of the gearbox where it's hidden. The bucking is properly installed but I'm not sure if it's leaking from there. How do I test the various spots it can leak?

Piston O ring
Cylinder head O rings
nozzle/tappet
hopup