I have heard that as well, but I don't believe a decent scope has that much distortion at the extremes of it's vertical limits. It seems to me if it did, then long range tactical shooters would make more of an issue about it than they do. I believe Burris makes a bigger deal of that possibility than is warranted when selling their Signature Zee rings. It's a bit of unnecessary hype to sell their product. Those offset internal rings are a good product, it just isn't necessary for all the reasons they state. Of course, I could be wrong.
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