HPA Gun not firing at good FPS or Joules

[Klesin]

Currently as the title states.

I have moved my Wolverine Reaper Gen2 from my MCX to a new L129A1 build that I am currently making. Issues I am having right now is that at 110/120psi with 0.30g bb's, I should be getting well over 318 fps / 1.60J, but I am barely reaching 270fps and I have yet to exceed 1J.

Current things I have checked:
. Tank / Regulator leaking = No
. HPA Engine In Line Loose = No
. Hopup isn't maxed out
. Hopup isn't too low
. Using correct BB's
. Seal from Engine to Hopup is good
. Bucking has no damage nor air leak
. Adjusted dwell with no result (Made it worse)

The MCX was a VFC Gearbox shell, and the L129A1 is an A&K SR25 Gearbox.

Any help would be greatly appreciated

 

[simonh]

Even with a very short barrel in one of my guns I get better than that fps with 60-70psi and the same engine. Your air has got to be going somewhere other than down the barrel, unless you have a very wide barrel?