https://www.dropbox.com/s/c59hbi2mf6m00o0/BDC%20S

I have created a BDC Range/Subtention Calculator in Excel which lets you calculate the various subtentions at different magnifications and use those subtentions to determine range estimations. It's the tool Nikon forgot to add to their SpotOn app. I run Excel on my smartphone and perform calculations in the field! Now you too can use your BDC reticle to range-find accurately. Enjoy!