My worst mistake, (although there have been many) is not rechecking the zero of my rifle after a fall. It ended up costing me a chance at a big mature bull elk. I fell in mid afternoon and my rifle banged pretty hard on the ground. Didnt want to fire a shot to check zero to risk spooking any elk in the area. The next morning I got up in the dark and decided to hunt in the morning and check zero during mid day back at camp. Well that morning I shot at the bull at approx 275 yards. Clean miss, no blood no nothing. Back at camp checking zero I found the gun shooting about a foot low at 50 yards.