This is certanly not a dumb question! The only way it would even be close is if Burris actually told you how to use your scope instead of assuming its customers were stupid!!! /ubbthreads/images/graemlins/grin.gif
Alrighty, heres the chart from the burris website.
what we are interested in is the far right column with the correction at 100yds info in it.
You have probably heard that minute of angle (MOA) is about one inch at 100yds.
Looking at the numbers we can say that the lines are
.8
2.4
4.6
7.2
10.4
and 14.5 moa as you go down the reticle. You can simply go to
http://www.eskimo.com/~jbm/calculations/calculations.html
and enter pertinant info for your gun.Set your output to moa.
From there just find the range that corresponds to those values.
Now if you are detail oriented you recognize that moa is not exactly one inch at 100yds. Its actually about 1.04719 inches at 100yds. crunching that math, you come up with values of
.8377
2.5132
4.817
7.539
10.89
and 15.184 moa.
Whether you need that level of precision I leave up to you.
If you need help on how to use the mildot section of your reticle to measure ranges, try this link. They have a pdf file that explains it nicely.
http://www.premierreticles.com/
If you are using it as a big game rifle, you might consider making up a cheat sheet based on the size animal you are ranging, so you don't have to do the math on most shots. Done this way, This reticle can be very fast, and very precise.