KA60 Gau minigun does basicly next to no damage to other vehicles , you need to shoot a littlebird like 500 bullets and im not sure if it even does anything then.
Also miniguns seem to lack power / damage / splash / spread , you need to hit infantry straight on to kill them , shouldn't there be some splash / spread so they would die or get wounded when you shoot quite near them , since of the high RPM.
Here is a video of helicopter minigun , notice how it wreks vehicles fast & has that powerful feel to it .
http://www.youtube.com/watch?v=juUJdzFFORs
that should shred the infantry but atm it lacks the power / feel , only straight hits count.