I don't know anything about the internal parts on the G&G but I do know the Classic Army sport line cuts a lot of corners.
Their gun feels cheap. They use cheap nylon bushings. The barrel is a thin cheap aluminum not a whole lot thicker than a drinking straw. The cylinder is made of the same thing...
The body plastic is not all that nice. Especially not as nice as JG's of similar price.
Check you're message box. I'm sending you another option.