WE Scar-L CQC AEG - Single shot stuck on full auto?

[RabidNinja64]

(Just a quick hand-me-down from my brother who wanted to sell it on and i got first dibs)

Took it into a game a few months back and at chrono it wound up shooting full auto on semi setting. I've yet to open it up, but i have a suspicious belief that it's the selector plate. that or it just needs a good clean, but apparently it's quite a common issue with these models?

Can anyone confirm this issue being a common one? or at the least source replacement parts? having a bad time looking for them. 

 

[jcheeseright]

It's just a V2 gearbox, either your selector plate or cut off lever is broken. 

 

[RabidNinja64]

It's just a V2 gearbox, either your selector plate or cut off lever is broken. 

Click to shrink...

So im assuming a standard m4 gearbox part change, correct?