[Kos-Mos]

What ever you do, it will STILL short stroke the pistion.

Count the number of teeth on a piston. Unless you can fit the same distance on an twice shorter arc of circle, you will get short stroke.

Ans since it is the last 20% of the travel that does most of the job, using that kind of sector gear would require an extremely stronger spring. (Something along M150 just to hit 400 fps mark) That would result in an increaded load on the motor, battery and the other [arts of the mechbox, resulting a very premature failure of the components.

You would then need to use a larger battery with a stronger motor to keep the same acceleration and ROF, even if a cycle does shoot twice.

It would also prevent you from using any innerbarrel longer than a G36/M4 lenght, because the piston can't travel as far and about half the cylinder will be redered useless.

Since most high powered rifles are aimed at markmen/long range shooting in semi, it defeats the purpose since accuracy will be dropped a lot by using a very short barrel.

The only possible usage of that kind of gear would be in a sub 350 fps setup, using a stronger spring (such as a M120), a short barrel and a larger battery.
It would be only usefull in CQB environements, where engagement distances are quite short.

Then again, bursting 30 bbs under a second to your buddy will eventually make them angry, and probably limit your possible game attendance.

At that point, one would be a lot more encline to use an AEP type weapon, such as an MP7 or Mach-10. Using a 7.4 lipo instead of the stock 7.2v pack and by doing minimal upgrade to the components, one would achieve a very high ROF, while keeping wear down and about the same accuracy as the double sector gear equiped rifle.