Hello all.
I decided to upgrade my MWS SOPMOD to fire 0.32g BBs at 1.1 J. Using a 370 mm long 6.03 mm tightbore Prometheus inner barrel, stock hop rubber, and Prometheus CNC Hop arm (rather than the SixG Nub, for which I got no email reply), I got 285 fps on a 0.32g, so just a little hot.
I installed the AngryGun MPA Ver 2 Nozzle, and identified many problems. The return spring was too strong, the C clip spring was dysfunctional, and the overall nozzle and BB loading knob (you know, the part of the nozzle that picks BBs up from the mag) lengths were too long. I fitted the nozzle with a Dynamic Precision spring set and the stock buffer sealer and had no problems... until I tried full auto. I got misfeeds, double feeds, and horrible consistency.
The stock nozzle setup fed fine, but ran too hot. So, I sanded down the AngryGun MPA Valve so it was narrow enough to fit into the stock nozzle, and sanded the three outer sides of the polymer end of the nozzle return spring flat so that the screw holes aligned with the stock nozzle.
I now have a reliably feeding stock nozzle that has an adjustable (and very consistent!) FPS, along with a spare nozzle that works fine on semi auto.
I would have liked to have paid less and just got a decent NPAS (the RA Tech WE NPAS didn't work for me) but hopefully this knowledge helps somebody else.
Can post pictures of the work if anybody is interested.