I was a member at a local club that was mostly shot gun outside and pistol inside, but there was also a 100 yardish rifle range in the back, where I'd spend most of my time. There were numerous occasions where I was peppered by shot while changing targets. If it had rained the night before, you'd also see little splashes in the puddles here and there.
As you got peppered, you could hear bulk of the shot touching down around you. If I had to guess, (based on the sound) I'd say the shot patterned on the ground in an oval shape probably 15 feet wide and 25 feet long. I've never measured the distance, and I have no idea which shooter at which shotgun station was swinging their muzze that far to be right, but I'd think that the distance wouldn't be more than 2 hundred yards. So I'd imagine a hundred yard group would be about half of that. As far as drop goes, who knows? These instances where we got peppered were over a 12ish foot berm, and fairly close to it, so they were coming back down at a pretty steep angle.
I of course don't know what type or size of shot they were using, but probably something like an 8. I expect getting hit with a goose load at 200 yards would be a different story.