I forgot camonitwit you are the almighty know it all god!!!! No one but the wife and I in the house so no one messed with it. I use a wheeler torque tool when I mounted my scope after lapping the rings and all screws got medium loctite. And of course it is a true Leupold scope since I bought it from them. Any other pearls of wisdom that you would like to share just drop them off in the garbage!! You think you know everything and everyone else is stupid. MarkSomething was loose or it was more than a few inches onto a table. Or someone was messing with it when you weren't looking. I've got way to much experience with bumps and knocks on a Leupold and they NEVER shift zero. Did you use locktite on the base screws? Did you use a torque wrench to tighten all the screws to proper spec? A miss was the best outcome possible. Could easily have been a gutshot loss.