The eye relief of a scope, is the distance between your eye and the scope at which you will see a full picture in the scope. If you move the scope closer to your eye, part of the scopes sight picture will black out. If you move the scope further from your eye, the same thing will happen. You may be able to adust a scope forwards and backwards in the rings but this adjustment must put the end of the scope at the correct distance from your eye when you are holding the rifle in shooting position.