O_O.....I haven't tried to understand the concept yet (mainly cause I haven't read the whole thing) But I read "cordless Power drill" and "Gravity feed". I would make sure there's an easy way to switch batteries, and make sure there's a way to have a crapload of ammo without making it to hard to lug around. I also have an idea, try to design a clamp or something that could close around a bar or some other fixed object and allow you to use it like a nerf gun turret. That could help with defense if you're team is being pursued.
Thanks for the criticism. I was also think more along the lines of SS2 and other long range pistols. In a war where an unlimited would be allowed, this would be useful. And with this, you could still hold your primary(depending on how you "stock" the wheel and how big/what shape your primary is.). You'd just have to have it between guns.