The trick is, move the front sight into the error and the rear sight to where you want to go.
Every rifle or better yet, every sight radius has its own formula.
eg; Lets say you have a sight radius (distantce between the sights) of 20".
If you move the front sight 1/2" , at 20" from the front sight the poi will move 1/2". At 40" it will be 1". at 60" it will be 1 1/2". That's basically it. So, measure your sight radius and translate that into the distance you shoot. Shorter sight radius, little is more.