I was wondering how much difference it would be when you sight in at 800 ft. above sea level then go hunt at 9000 ft. above sea level?I would think you would shoot higher?I wasn,t sure so I drove 90 miles just so I could sight my new 50 cal. Omega in at 6000 ft. for a upcoming Nevada hunt.They sent me some 240 grain hollow point lead sabots/ Cheap Shots / that I used.At 30 yards right out of the box I had 1 inch groups about 1 inch high and 1 inch to the right.I adjusted it to the left a little then went to shoot at 100 yards and was shooting to the right 2 to 3 inches and about 5 inches high with 2 inch groups.I got it to group 3 inches high and 2 inch groups so I was pretty happy so I put my new target out to 150 yards and shot 4 times and had a 4 inch group from the center of the bulls eye. The only problem I had was loading the bullets, the barrel has a real tight fit and the last inch of the rod was tough to seat the bullet,also I cleaned real well between each shot so I don,t know why this happens maybe just the type of sabot? and yes my shoulder does hurt a little oh yea I was useing 2 50 grain 777 pellets ....Devlin