At a thousand yards, that balloon is less than 1 minute of angle wide. :o
Jerry's youtube channel is full of such circus-stunt shots. He's the best shooter in the world, hands down. The man is a robot. It's the only logical explanation.
It's kind of depressing, really, since I know I'll never be as good at anything in my life as he is at shooting. But it's inspiring, too, because it reminds us that the ceiling of human accomplishment might just be a lot higher than we thought it was. So be like Jerry, and aim high. :D