Check out this contraption by the Brain Exploder where an APS CAM870 is underslung a Cybergun FAMAS F1 AEG... "So I decided to take this monster of a creation out to Hollywood Sports Park, I did not have the greatest success but most of that is operator/situational circumstances. I did end up frying the gun the last round of the video, I think the 11.1V battery was just way too much juice for this gearbox. If I ever get this thing fixed I might give it another go but I'll probably be losing the shotgun as it is just added weight that adds little function."