Several of my FB CW reenactors had jokes about this...never underestimate the power of a cannonball! Those things do KILL or smash things to pieces. Many of them were saying, "Are they trying to do a Jenny Wade stunt"?
I think the people that fired off the cannon probably miscalculate the distance, weight of ball, amount of powder and how high the barrel was pointed at. I think it went over the protection hill and it ended up in the subdivision behind the range. I don't think its the same place where they do all of their bombing experiments because if houses were close by, their windows would shatter everytime they blew up.
I am certain that it was an error! I hope they will broadcast it because it would be so neat to see that!