[MaciekA]

The above posts are super solid and I agree completely.

Kos-Mos' post is not a completely true statement... HOWEVER, his heart is in the right place and he is describing a problem that inexperienced AEG owners and/or doctors will experience from time to time. Pre-engagement is a total bummer when it happens.

The problem has been solved and re-solved by large numbers of techs out there, and it's also true that often it doesn't even need solving in the first place in some setups. Extremely high rate of fire issues come down to a few core issues.

Piston return time: Can we get the piston to return back to the front of the cylinder before the sector comes back again? I've seen data recently that indicated that the return time on a piston in a given setup was around 6 to 8 millseconds. Ignoring the position of the gears for a moment, that gives enough piston-return-time headroom for an astonishing 166 rounds per second. Even a conservative estimate of 12ms is still going to net you well over 80 piston returns per second.

I personally believe some number of pre-engagement cases are not due to the piston being too heavy, but experiencing too much friction on its way back to the front of the cylinder. I regularly run into pistons which are unable to move freely in the gearbox. When you guys are testing your mechboxes before final assembly, one of those tests should be to put the completely assembled piston into the gearbox without the spring or spring guide or gears and just see if it can drop up and down the path by using only gravity. Some of you will be surprised by the results. Something to think about...

Angle of engagement: can we ensure that the strike surface between the sector gear and the piston's first tooth is a 2D rectangle instead of a 1D line? It's also my opinion that a large number of people who destroy pistons and/or gears on high RoF setups are actually just not correcting for AoE and misdiagnosing or "underdiagnosing" (i.e. guessing) their pathology. Again, the incredibly fast return times of pistons in low-friction conditions would support this theory.

Finally, there are a number of ways we can lower velocity dramatically while still using a M120 or M130 spring, to ensure hyper-fast piston return time:

For example you can rob your cylinder of volume using sorbo and remove length from your barrel. Or do some fun dual sector gear stuff (edit: I meant to say short-stroke). In either case, these things require torque and power delivery, things I personally believe are the "pillars of the airsoft mechbox", but are still largely ignored. I'm still stunned when I meet people who have airsoftmechanics accounts and are running Tamiya (okay okay, you know who you are and I know you have a kickass excuse).

Unfortunately, those of us who know about these things are still fighting the "longer barrels are better" myth and general lack of awareness about neodymium motors and large LiPos, so there's a long way to go before these become viable suggestions and common knowledge. Until then, the PE boogeyman will reign...