You said dead on at 100 yards. Not enough info. Dead on to some folks could be a 4 shot group in a 2" circle. Let's say your group was 1 MOA. That is 4 MOA at 400 yards. Are your shots at 400 yards all within 4 MOA and just 5"s to right? I would make 5 shot group at 400 yards and adjust scope to where the center of that grouping was the center of your target. When you do that and go back to 100 yards I bet it will surprise you how close you are the X.
He confirmed zero on the second target at 100 yards. He shot three on the first target into the left lower diamond. The picture is posted on Buzzyb's 4th or 5th entry, and its a 3 shot one ragged hole group about 0.3 inchs left of center and dead on vertical at 100 yards.No the 100yrd target is 3 shots
With the Berger 215 @ 2976! A 2mph wind moves it Nearly 5” right at 400 yards so. I think you already know the answer to this and are trolling a little, but if not then, just Use your Kentucky windage and hold more “left” and send it. Good shootingNo I don’t . How much will wind effect the poi at 400yds
I adjusted zero with this target those targets are the same at 400 after I set zero.
What caliber rifle? What power scope? After how many shots? In addition to the information offered above regarding scope alignment is the following experience I've had. Shooting a 300 win mag I took 10 shots to get a good 100 yard zero. then I went over to the 500 yard targets only to find I couldn't hit the broad side of a barn. Came back to 100 and was dead on. A young whippersnapper who had attended Army Sniper school at Ft Benning suggested that I was getting a mirage effect from heat waves coming off the barrel. The magnums heat up a barrel a lot faster then standard calibers. High magnification exacerbates the effects of heat waves so that it looks like the shooter is trying to hit a moving target. A sheet of aluminum foil, shiny side down, slipped between the scope bell and barrel, the length of the barrel gave me a consistent 2" group at 500yds. It's always something. At one time I got paranoid if there was someone at the range watching what I was doing. Sometimes really good info can come from those casual observers. What also helped after the aluminum foil was dialing the scope back from 15x to 4x. The heat waves were no longer magnified. Also I'd put the spin drift theory to rest as well. After eliminating the possibility of a mirage effect, and after going through the scope alignment advice above, then at 400yds dope your scope "n" clicks to the left, If its dead on then, spin drift is probably contributing to your problem, and you must keep that in the back of your mind whenever you shoot at those distances.
You held the rifle different.