Re: Ranging with a scope
If I am remembering correctly, the NPR2 is 2moa vertical and 5 moa horizontal when on 22X. As Broz mentioned, there is a dot at 11X if you want to use twice that spacing.
The 5-22X versions work as advertised (for spacing and ranging) on 22X.
The 3-15X versions are supposed to be used on 15X.
But as mentioned above, any power works really; it's just that the spacing will change if you change the power.
Yes, we can range somewhat with a duplex reticle. We have to know the subtention or distance between crosshair and thick post at 100yds. We also have to know the size of the target and figure out on what power that particular target brackets the reticle at X distance............It does work, but not nearly as accurately as an moa reticle, and it relies on moving the power dial until the animal brackets just right in the reticle.
Using the Moa Reticle is simply size of target divided by how many minutes covered in scope..........15" antelope covers 5 minutes of reticle= antelope is roughly 300 yds away. (to be as precise as possible, we have to use 95% of 300, or 300-15=285 yds)
Ranging with the reticle works out to a certain distance so long as we know the correct size of the target. Laser range finders obviously work much better, and are much more precise; but it's always good to have a backup plan in case the rangefinder quits, or gets broken, or it's too foggy/rainy for it to work right.
Aim small = Miss small