Before:
After:
How I did it?
I wish I took production pics but heres what I did. My friend actually has the exact same gun so I did 2 at a time but, I first covered up anything and everything I didnt want painted at all so I completely wrapped the end of the barrel, I covered up bb feed, i covered up the bolt, and i covered part of the upper receiver where there were holes to the gearbox. I sprayed the grip, stock, and hand-guard with Krylon camo grey. Then a second coat of the same.
Once that dried, I wrapped them with the green painters tape stuff and sprayed the rest of the gun with the krylon camo black. 2 coats again.
I then took some silver arcrylic paint from citadel paints (warhammer =P) and drybrushed all metal.
I then took off all the tape and voila. Awesomeness.
The suppressor is my S400 I made today. Other thread in airsoft discussion.