Ok so what I came up with is the gaps in the reticle are calibrated to show 60 inches tall and 39 inches wide and the corresponding distance shows sitting on the horizontal. My quick math(please check it) gives me these values for the "spaces" between the lines for both the vertical and horizontal, all given in mils.
500m= 3.04 tall, 1.98 wide
700m= 2.17 tall, 1.41 wide
800m= 1.90 tall, 1.23 wide
900m= 1.69 tall, 1.10 wide
1000m= 1.52 tall, 0.99 wide
1100m= 1.38 tall, 0.90 wide
1200m= 1.27 tall, 0.82 wide
Again, that's in mils and thats my quick math based off of how the reticle is designed to be used. The Army has a tendency to work in "target sizes" as much as they can, I guess its quicker/easier for the average guy to be effective with. I hope this answer helps some.