I tossed a 500lb LGB about a mile past the range fence once, luckily it was into an uninhabited canyon area. I also saw the hud tapes from a 4-ship of F-15Es that dropped a total of 24 500lb high-drag mk-82s about 2 miles short, barely making it inside the range boundary fence. We live/breath ballistics, and still make the occasional hideous mistake. So it doesn't surprise me that mythbusters eventually lobbed something off the range.