One Minute of Angle is 1.0472" per hundred yards. So one Minute of angle at 500 yards exactly 5.236 inches. Many simply say 1 inch per hundred yards and 5 inches at 5 hundred yards and this is fine until it is compounded. example if one needs 25 minutes of angle correction at 1,000 yards that is a correction of 261.8 inches. A correction of 25 inces per hundred yards (IPHY) is 250 inches an correction difference of 16.8 inches a significant amount of difference.. Many scopes adjust in IPHY and a few of them adjust in true Minutes Of Angle, such as Nightforce..
range it,check the wind, dial in correction, aim and only one shot