Scott, Read this about a year ago and it seems like it disproves the old story about cant being worse when scope is mounted high, I have shown it to many high quality shooters (some of which were snipers in the service) and they would not con seed to the theory. I can honestly say that I have not see ant difference when having my scope mounted higher than when it was mounted lower. I can say that canting of any amount no mater what the scope height will cause a change in POI that is for certain so I have to kinda go along with the explanation. Whats your thoughts as you have been at this a lot longer than me? J.L.
If one scope is mounted above the other then LOS for the higher scope would have to be angled slightly more downward IN RELATION TO THE BORE in order to hit the point of aim than would LOS for the lower scope.
My way of visualizing this-Consider X scope mounted 1 inch above bore and Y scope mounted 2 inches above bore, both zeroed at 30 yards. Tilt rifle 45 degrees clockwise (crosshairs still on aim point but muzzle has now moved left of vertical). X muzzle is now 1 inch low and left along a 45 degree line while Y muzzle is now 2 inches low and left along same 45 degree line. Different related to mounting height. At 15 yards X point of impact is 1/2 inch low/left along 45 degree line while Y point of impact is 1 inch low/left along same 45 degree line. Both hit point of aim at 30 yard zero. At 45 yards X impacts 1/2 inch right while Y impacts 1 inch right. At 500 yards these distances become roughly 15 inches for X and 30 inches for Y. Depends on target size but one would likely produce a hit on a 20 inch target while the other would miss. Scope height does effect cant error. It seems to be a small difference but it certainly appears to be different. The difference becomes progressively larger at longer distances but the cant error itself seems to be more important than the difference in mounting height. There was a statement posted recently about military concept being 6 degrees of cant producing 55 inches of error at 1000 yards. That would be for ONE specific mounting height. Change that mounting height and that error amount would change, albeit probably very slightly. Seems that the cant itself is the primary producer of the error but mounting height has to be a factor.
I don't see how you can argue the physical situation I laid out. It doesn't matter that the 45 degrees is extreme and no one would shoot that way. It does matter that it illustrates that different mounting heights will have a different point of impact with the same amount of cant.
I still don't agree with your view on the mil dots. Yes they would be roughly aligned with each other but not similarly with the bore. They would both converge on the bore and would have to do so at different rates. I'll still believe that mounting height will have an effect on cant error.
Anyone can go to their back yard, "correctly" mount a scope with low mounts and then with high mounts, fire shots at a consistent amount of cant, and OBSERVE the change for themselves.
Think of it more simply if it helps you understand-do the two different mounting heights hit at the same point from muzzle to zero and beyond even if "correctly mounted" and held perfectly level? No, they do not.
...They only hit at the same point at the zero distance....
...Bottom line is.... align the vertical reticle with the bore when mounting the scope.... and then hold the crosshairs level when shooting.... Bob
Sorry, but how is "use your mil-dots/stadia as holdover aim points" different from "aiming high"?
Quote from: bandg on November 27, 2018, 09:32:30 PMSorry, but how is "use your mil-dots/stadia as holdover aim points" different from "aiming high"?