[lurkingknight]

I've run out of ideas on this. My p90 that was once shooting awesome has now developed an inconsistent fps problem.

The issue is that on a full midcap, it will shoot inconsistent fps on non consecutive rounds until the mag is 1/2 empty then it will resume normal function.

Feeding from mags is fast, and there seems to be no issues with BBs leaving the magazine.

nozzle is new, cylinder head is new (replaced as a precaution also the sorbo was tearing the rubber patch of the old cylinder head.

When it shoots consistently, it will shoot +/- 3 fps.

I've also tried different brands of BBs with the same result, so I think it would be save to assume it's not a BB issue.

I have reseated the barrel in the hop up bucking 3 times, each time with the same result.

This gun functioned properly for about 2 years, it's now out of the blue decided it wants to cause trouble for me.

When it's shooting fine, it shoots 305 with .32s When the mag is full, every 1-2 out of 3 shots will come out at about 120fps.

The only 2 things I haven't replaced are the tappet spring and the tappet plate. The tappet spring is a bit tricky since it's a compression spring and nobody sells that.