So your good at 100yds, then are you saying you move to 200yds and your off up to 8"-10" to the left? or as soon as you go from 100 to 120yds your off as much as 10"? If there's no wind adjust the sope and bring it to the right, then shoot and get in on at 200, then go back to 100 and see where your at.
If there is wind then it's the wind to start with, and dont drink any coffee or cafinated beverages, caffine can give you the jitters. There's a Big diffrence shooting at 200 vs 100. Turn your scope on say 3-4 power and hold it at the target and look through it, then turn it up to 9 power and look through it, the scope magnifys the tiniest movement and what you may think is a stedy shot is not. You have to be dead solid at 200 or you will be all over the place.
(BP)