aye, I think trying to match the fps of a tbb when using a wbb is the issue. Gonna go back to a tbb and have also ordered the carbine kit for it too so will extend the barrel length allowing me to drop the psi further. I'm working on reducing the recoil too with a new nozzle and stiffer recoil spring and some other bits.
I saw your FB post
Im not sure that the nozzle will affect the recoil, as all three nozzles should perform identically once the valve in the nozzle closes and starts the blowback, but using a longer/tighter barrel will let you reduce the FPS.
Now im slightly concerned for mine as ive just fit a 6.23 barrel and am just waiting for my high power nozzle to arrive so i can get the FPS back up from around 276 fps
something has just struck me, That FPS is actually calculated from the energy, as in, I actually measured a 0.25g BB and converted its energy to the equivalent of a 0.20g BB, but chronoing on a 0.20 gave me 245fps from memory, thats a 12% increase in energy!
I,m gonna break out the chrono later and check that again...