Need help with my M4 EBB
 

Ok so heres the problem: when I try to shoot it the mechbox just seizes up or the piston will move half way before getting stuck.

I have opened it and every part is in order and nothing is cracked and/or broken. Funny thing is if i put everything back together without the spring, the gears and everything else will spin freely like its suppose to. I think it might be the spring but its only a M120 and im using the blue JG motor i took out of my other gun (that other gun has a M130 spring installed so like what gives?). I even tried hooking up my 9.6V battery to it but its the same.....

So does anyone have any ideas? I really dont think its my motor since it works fine in my other gun. But this time im pulling a weaker spring.....

i had a similar problem with one of my g&g's. do you have a upgraded piston head and spring guide to bearing ( even if the are stock bearing). there may not be enough room for the spring to fully compress/piston to move all the way back, causing it to jam.

what i did was remove the bearing on the stock spring guide and put it all back together, i haven't had a problem with it since.

if you do have these parts give it a try and update if it works/dosint work to see if we can get this thing going for you.

Tm sopmod?

Naw it is APS. I ended up getting a guarder infinite torque motor and poof fixed. Turns out my shitty CA motor couldnt pull a M130 spring.......

Anyways; the aps gearbox has a cool design. They fixed up some annoying bits like the ARL. Its really cool and made putting the thing together much easier.