Re: Hight End AR Hunting Scope
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SWFA</div><div class="ubbcode-body">243Varminter,
A common misconception is that you have to have a scope with a large objective in order for it to perform well in low light, this is not true.
Low light performance is primarily dictated by the quality of the glass and coatings. A scope with a 20mm objective can be just as bright as a scope with a 56mm objective, it will just do it on a lower magnification. The only benefit of a very large objective is the ability to use it on higher magnifications in low light.
I assume since you are building a mid length AR as a hunting rifle and the fact that you inquired about a 2.5-10x32 NF that you don't plan on this being a long range big game set up.
TheOneTwo's suggestions are spot on, I wish this Swarovski was less because it would be perfect.
http://swfa.com/Swarovski-17-10x42-Z6i-30mm-Riflescope-P7604.aspx
The little NF would work and is better than most scopes out there. It's optimum setting for low light would be 4x-5x. We have one on The SampleList right now for $1199. There are also many Swarovskis, Zeiss and a few Leicas on there (priced right) that would work very well.
http://www.samplelist.com/
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Spot on advice. If you want to do some quantitative analysis of light transmission just calculate exit pupils for each scope. Divide the objective size by the magnification. Anything over 7mm or so is wasted (average size of a human pupil).
So a 2.5-10x32 NF has an exit pupil of 32/2.5 of 13mm at 2.5x and 32/10 or 3.2 mm at max power. So you can see that even if you put a 100mm objective on a scope, it would not make the image any brighter at lower powers.
Here's an easy demonstration of that:
http://www.youtube.com/watch?v=GBS0KVxBmRA