AEG making loud grinding noise, spring appears to be jammed

[Broken34]

Ok I think we solved the problem. (or at least one). There appeared to be some little piece of a screw that was jammed in the track that the piston slides on. It was very small and once it was removed the piston was cycling back properly when I manually turned the gears. I now have the gun fully assembled and the gearbox is cycling fine again. But now when I fire the gun it is firing 2 bbs at once and they are sliding out of the barrel. Hop up needs adjusting maybe?

[ThunderCactus]

Turn the hop off, then slightly on
It'll jam if it's on too far and misfeed if its off
As for your specific issue, you probably just reassembled something wrong

[HKGhost]

Before you start trying different things without knowing how the gearbox is suppose to work, watch and read everything about V2 gearboxes. Once you've understand everything, then try and fix it. But I think you should look for a gundoc in your area. You might be able to diagnose the issue, but due to your lack of knowledge on how the internals are suppose to be, you might be just digging yourself into a hole.

[Broken34]

Ahhh, nevermind. Piece of shit is jammed again and now it's not moving at all. Motor is heating up and so is the battery. Don't buy one of these unless you want it to break after only 25 shots.

[K3vX]

sigh...