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Version 3 mechbox anti-lockup tip

I just got finished with addressing an issue I think is worth sharing. As many of you probably know, “lock-up” is a risk with Version 3 gearboxes firing in semi-auto.

What is Lock-Up? Every now and then, if you are firing in semi-auto with a version 3 gearbox you might get what is called “lockup”. It’s when the cutoff lever inside the gearbox disconnects the trigger BUT the trigger doesn’t reset. So you can pull the trigger all you want but nothing happens. To fix it, you briefly switch your gun over to fullauto and pull the trigger. The gearbox turns over enough to “get past” the lockup and you’re ready to rock again.

Now for semi-only guns using a Version 3 gearbox this can be a problem. You don’t want to disable fullauto on your selector completely because you’ll have no way to clear a lockup. MOSFET units don’t solve the problem entirely because the problem is in how the gearbox works.

Well if you are using a MOSFET unit (like our Trigger Master MOSFET which has semi-only firing modes) there is a way you can be sure you can always clear a lockup!

All you need to add to your MOSFET unit is some thin wire and a small button. Wire it up and tuck it in somewhere you can get to, but that is still hidden and where it won’t be hit accidentally — like under the receiver cover or something.

That small button wired in parallel with the trigger wires will run the motor whenever it is pushed – it’s like a second trigger. If you get a lockup, just push that little button to crank the gearbox over just enough to get past the lockup and reset the trigger! It’s just like switching your gun over to fullauto for a bit, except that it works EVEN IF YOUR GUN DOESN’T HAVE A FULLAUTO SELECTOR SETTING.

See this post for details on the wiring. (That article was written for the purposes of literally making a dual trigger, but the details are the same.)