Look, the idea of having heavy with an aircraft weapon is awesome, but it doesnt fit tf2 for the following reasons :
1. This is based off of the real thing to much, and tf2 weapons are not meant to be EXACT copies of real weapons.
2. If this gun was in tf2, it would be like a freaking fully automatic rocket launcher (damage wise).
3. had a weapon not be exactly like the real thing, then it would just be a skin for the regular minigun, which is not needed.

I am not trying to say the idea is bad, it just is not a good fit for tf2

I think that its ok to share simularities with real things, but it also needs creativity

For example, look up Olga, The perfect killing machine. Olga is very original, but has similarities with the PKM.

Heres my conclusion: While the idea is good, it isnt for tf2, as the gun has to be realistic, because an m61 isnt something that can have original changes, this isnt meant to be offensive, but it just wont fit. If i knew how to make stuff like this, i would work on an M2 browning (gotta love that 50.)