What It's Like To Target Practice With a Machine Gun at 1200 Meters

At 1:25 into the video, two men have a conversation:

"See how much it disperses?" (meaning that at 1200 meters, the shots land a good 5-20 feet apart from each other).

"Is that wind?"
"No, barrel flex."

Then they show the gun shooting again, and you can see that the barrel, and the gun are moving - as the result of the intense vibrations of a machine gun.

Stephen Paddock was not shooting from 1200 meters. He was shooting from about 500 meters.