It depends if you near or far from the person to see the damage if far you will get less damage but near you will get him about 20 bullets my guess
True, but the problem is:
1. Minigun's bullet speed is pretty high, it shouldn't lose so much damage over a long distance.
2. The Minigun's bullets tend to be inaccurate, shooting in a slightly up-and-down pattern even without self-bink.
3. The registration for Minigun bullets is particularly bad. Don't forget the lag and ping.
4. Considering how fast the minigun fires, you're gonna spend quite a lot more than what is needed since it takes time for you to realize and react to the fact that your opponent is eliminated etc.