I have the vortex viper 6-24x50 pst and was at the range and was the first time I've dialed dope for the given range. I shot groups at 100 and was dead on the bullseye then dialed out to 400 yards and shot. When i dialed back to zero at 100 and shot. I was grouping about an 1in to the right but dead on. I then dialed my windage to get back to adjust for it and was back to dead on. After that i did the same thing, dialed to 400 and came back to zero and was perfect and went to 300 and came back and was still dead on elevation and windage. Was it just a fluke or is the scope not the best for dialing dope on the turrets. Its the best scope i could afford at the time and offers all the features i liked. Im guessing it was me but it grouped to the right after the first time but was fine after that. Any ideas? Is it a repeatable scope