Multiply The observed difference between your actual point of aim and impact in MOA. Proceed to then Multiply the Minute Of Angle per click indicated on your buttons or turrets by that number (calculated from above). If it isn't listed, consult your optic's manual. For instance, if your turrets specify "half an MOA" or "0.5 MOA" per click and you observe a 40 MOA adjustment is necessary, multiply 40 by 0.5. this brings you 20 clicks.