[AndyTheBear]

Correct, and clustering within the Poisson distribution is well known. It's why, for example, in a locker room three random dripping wet guys all wind up within a few feet of each other with no one else in the room.

I think the guys in the locker room have far more control over where they stand than the shooter had over whether his rounds hit an individual target. I don't think its reasonable to model it as a random distribution of any kind, but to look for other causes as to why they are close together.

[FredZarguna]

Subject to the assumption that they don't know each other and arrive randomly, it's Poisson.

If they know each other, something else altogether is going on.