Ok, Im at the range, my scope is a vortex viper pst 6-24x50 mrad/mrad I fire a 3 shot group at 100 yards and the group is 1 inch high from bullseye, How many clicks would I need to correct my zero?
To answer the question, I'd take 3 off of it..each click is roughly 1/3 of an inch. But stop thinking inches and read your reticle, it will tell you what to do. And if it's ffp it will never steer you wrong. 1 mil is always 1 mil regardless of distance. Measure the shot with your reticle and make the correction, whether it be with reticle (hold over/under) or turret.
Agree with 3 clicks down and you should be good. I run the Tall Target test as mentioned by Bryan Litz in his instructional DVDs. Lots of great info for the price of the 3 DVD set. (I have no connection with Bryan, but also find his Applied Ballistics App one of the best once you learn how to use it). All scopes tend to track fairly well, but some much better than others. I dial for distance and hold for wind. The more you practice in different conditions and altitudes and the better you get at judging wind the more accurate you and your rifle will be. Practicing now on ranging with the reticle and scopes I use, since most range finders othe than the expensive Vectronix are not that accurate. Have fun and good luck. Always something new to learn to improve your skills in this sport!