Norway, I'm not sure on the theory, but I have tested all sorts of scopes for parallax at a variety of ranges. Just walked out side now and tested a 3.5-10x40 Leupy and a 3.5-10 Swaro Z3. They both had about 13 or 14 inches of parallax at 1000 yards. (34cm at 900m approx) That's too much potential error in my opinion for long range game animal shooting.
Greg
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