Need a little help with interpreting scope data

[DZelenka]

Originally Posted by Wingnut

For 15 MOA of adjustment that is pretty good. It would be a pretty small adjustment to try and get that angle of degree out. You could try but might not make it back to where you are now. Now the real test shooting it at 600 yards. This will show you your spin drift and a new factor to adjust for. As for the dispersion left to right at your zero. Does it do it through the whole adjustment? At 8 MOA is it half as big of group? If it were bedding or an issue with the rifle you would see it throughout the adjustment. It might be an issue with the scopes erector setup.

At 600, it seems to be about 1 MOA right of my wind call. 1/2 MOA of that should be spin drift so there is somewhere between 1/4 and 1/2 MOA misalignment. You answered what I was asking although I would like a few more responses. Getting it much better than I have it may be chasing my tail.

It isn't a rifle issue, it seems to be a scope issue. I don't get any of the horizontal dispersion when I add elevation. The last 3 shot group I shot with 9 MOA on was slightly over 1/4". I thought about getting a 10 MOA rail, but it would raise my scope which I don't want to do. Plus, I may have to screw with the crosshair alignment again.

Dan

[paphil]

Dan, What you have is an internal scope problem. Not really a problem in your scope because the difference between your vertical reticle and the scope adjusting mechanism is so small. From what your picture shows, your adjuster in the scope leans slightly right. Many scopes have this problem, some lean or cant as much as 4 degrees, Yours looks to be about 1.5 degrees. I also once thought that rotating the scope in the rings would fix the problem ,but doing the same T test that you did proved me wrong. I found that the only way to correct was to use a scope level canted slightly in the opposite direction. The goal being to shoot with the adjusting mechanism perfectly vertical even though the reticle will be canted slightly left in your case. I go one step further and cant the scope (and adjusting mechanism) an additional 3 degrees left and install the scope level in level position to get the gun to shoot one minute left when turned up 22 MOA for 1000 yards on the T test. This eliminates spin drift from the equation, but you have to rely on the scope level every shot. I find that the only time I notice the reticle being out of square is when shooting targets that have been set with a level.