I sight in and shoot my rifle in nd. the area is around 1300 feet above sea level. I was comfortable shooting out to 400 yards. I went to Wyoming antelope hunting and I think the elevation was around 5000. I shot my antelope at 400 yards and it did not seem to change the point of impact at all. I did shoot at a target out there before I shot at the antelope. but my question is there was no change that I noticed at 400 yards going from 1300 ft to 5000 ft in elevation but would I notice a change in point of impact going from 1300 feet to say 9 or 10,000 ft? I've just seen this topic on long range pursuit and I was curious what other's opinions are.