Re: Parallax question AO or not.
Just my opinion,
If you are making a carry around gun that may need to make a quick shot under a variety of ranges, I go wituout the AO and practice getting a consistant cheek weld to try and reduce the amount of misalignment between my eye and the scope.
For a dedicated LRH / Varmint rifle where ranges are longer and you have more time, I use it.
And yes, there is more difference the closer you are. Look at a scope with AO and it will usually have markings for approximate ranges (the word approximate being a gross understatement!). The may be at 20, 30, 50, 100, 200 and infinity.
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