If you live at an elevation of say, 700 feet above sea level, and plan to hunt in the Gillette or Douglas areas of Wyoming, make sure you sight in your 280AI once you arrive at the ranch you will be hunting on......You will be hunting at an elevation of close to, or over, 5000 feet above sea level.....and POI can change enough to result in a miss or bad hit on an animal with a kill zone about the size of the monitor screen on your computer......
My 270 Winchester printed 2 inches higher at 100 yards than when I sighted the rifle in back in Manitoba....
Good luck and if you are in Douglas, stop by the Labonte Inn for their great dinner and buffet...