OK, understand you have it sighted in now. Next time you get a chance, remove both bases and flip them over on a flat surface so that the top of the mount is sitting on the flat surface. Now butt the 2 pieces together so that you can see if there is a difference in the radius or the height from the top of the radius to the top of the mount. Basically, if they are the right parts, the 2 cylindrical sections should form a continuous surface with no step or other mismatch. I have seen plenty of times where people fudge things by taking several mounts out their packaging and then putting it back wrong. So you end up getting something other than what you think you have, even though the box has the right info on it. I have found 204 ruger bullets inside 223 cartridge packaging, for example. From Hornady. Not all of them, just one.