[mcguyver]

The trouble encountered with gear compatability usually begins and ends with the sector gear. The size of the tappet nub and it's position on the gear, coupled with the profile of the tappet is what pulls the tappet back at precisely the right time. This is what "times" your nozzle engagement. This can be altered by changing the tappet, the sector gear or by addition of aftermarket clips to the tappet nub. Small changes is size or positon of the nub on a different sector gear can and will have a big impact on the engagement of the nozzle.

This is why companies like King Arms makes then, and why changing tappets to a different brand can have differing effects.

If you carefully compare the G&G sector gear to the Star gear, and paya close attention to the precise size and position of the tappet nub, you may find there are differences there that will explain your problem.