[eV.Viper]

yeah sometimes everything seems to be ok, but maybe a little piece is reverted, or misplaced.

You have to look carefully at each parts of the gearbox (take a look at mechbox.com). Maybe you'll find the solution, maybe not.

Also, if everything seems to be correct for you, you can still send your gun to a gun doc (I know i've said it very often, but it will save you some time and frustration lol).

I know there's some good gun doc in ontario, and if you're willing to ship it a bit farther you can still send it to kos-mos or me.