Guys my suggestion is to go to Nikonhunting.com, click on the Spot On logo in the upper right corner.
You'll have to register then it'll take you to the Spot On Ballistic Match Technology Program. This site is a shooters Nirvana. It will allow you to enter all your load data as well as the type of scope you are using, it'll help you with site-in data as well. You can then view the distances each circle represents in replationship to your specific information. Pretty cool stuff. I printed off a Field Reference Chart for my .300 WM and 5 year old BDC scope and taped it to my rifles buttstock. Take a look at it and let me know what you think.
Nikon Pro Staff