I have a TM mp5 with a full tune kit and a SP120 spring. I changed everything mechanical in the mechbox.(gears,piston,piston head, etc.) I made sure the shimming was good. But when i put everything back together, I fire the gun on semi and it fires like 3-5 shots then it stops. It happens on auto to. I called the local shops and they said its the shimming, but i know its not that. I have a 8.4v 1300mA battery. I am thinking that it might be the battery is to low of a volt So i might have to go up to a 9.6v. But before i buy a 80$ battery i want to make sure that its the problem. if its anything else let me know please.
The problem is likely the battery, but you don’t need a 9.6v (won’t fit anyway). just charge the old 8.4v. what’s happening is the battery is just out of juice so it’s only lasting like two shots. if you already have charged it, then it’s fried and you just need a new one. In that case you might actually want to get a 9.6v since you’re pulling back a 120. make sure the battery is the problem first though (borrow one and test it) and a 9.6v won’t run you 80 bucks. You can get an intellect battery (reallyyy nice) for about 50