Just to be clear.

You're trying to unscrew this thread cover right?

http://i41.tinypic.com/2r2lpxj.jpg

That thing isn't secured by anything else but thread. So if it doesn't unscrew, threads were probably damaged at the factory or during your adventures in removal. So really your only option left is probably to replace the part itself. It's too bad because that gun is a beast. Nothing comes close to it in performance in the 300$ price point. I know my local shop would take care of something like this under warranty, not sure about whoever you bought it from. You can contact G&G directly, I hear they have great customer service.

He wanted to do something like this.
http://airsoftcanada.com/picture.php...pictureid=6038
Unfortunately the threads for the barrel to 3 lug are about 12mm, not 14mm.
In the photo my 14mm adapter literally slipped right over the barrel threads.

So i got it to work, and even made a tutorial! Heres the link
http://airsoftcanada.com/showthread.php?t=161036

G&G MP5 Trouble
 

Was this ever solved? I'm trying to remove my 3 lug flash hider from my G&G MP5. I'm pretty sure it's threaded onto the outer barrel, but I've tried to remove it. Which way does it twist off? Help PLS