Went out the other day and re zeroed and tested my 338 out to a range of 940M. I chronoed the rifle at 2852 av for the 300 smk. I shot the targets based on this velocity figure in exbal and was fairly satisfied that we were dead on. Went out 2 days a go for some more shooting. Lined up the 695 M target and entered the new conditions. Got the new dope ( Shot the target with the same ups 15.75 as shoot one. Got a group that was 9" low ? So went back and re validated and got a corrected velocity figure of 2819 fps. This was because I needed to come up around .5 moa. 16.25 moa put me close. I just wanted to know if you go out and practise, is it normal to have a trajectory validation changes from session to session ? From what I saw Shawn Carlock talking about on his LRH DVD, you will find an average velocity based on multiple sessions of testing ? Some days the gun is looking quicker or slower. Then take the average to run with ?? Does this sound right ? I checked all my rig and it was all square. Just wondered if any of you experience this and if it is normal for exbal ? The only real diffence in conditions was the RH had gone from 93 % in shoot one, to 79.4% in the second. BP was 29.72 To 29.88. Thanks again all !!