Recharging would be a bear. Would a small alternator with a belt help to keep up the charge?
It was fun to watch, but a little demented. For the same weight, I'd rather have an AR-15 with 1250 rounds of ammo than a minigun with 200 rounds of ammo. Of course, the minigun does look a lot cooler.
I had an opportunity to talk to the guy that owns THAT mini gun at the Knob Creek shoot. He told me how they had to rig it to be fired by hand. First of all, blanks have no recoil. No one can hand hold a mini gun being fired because the recoil is something like 600lbs continuous. AHnold could have pointed the gun at the ground, and if loaded with live rounds, taken off like a rocket. The gun ran on 28v aircraft batteries, they just ran the power cable down the actors pant leg to the huge battery next to him. He said it also took some technique to fire blanks from the gun, because the damned thing ate 1000 rounds in ten seconds! Your back pack of ammo goes from heavy ass hell to empty like someone just ripped it off your back, all while you are trying to act and fire a very intimidating weapon.
I was also told that the director believed that the audience would not believe what the gun actually sounds like. (a big chainsaw) So they recorded the sound of the gun being dry fired with no ammo, then mixed in the sound of an M2 fifty caliber. Because that’s the sound he thought the audience would associate with a big machine gun.