I mentioned a few weeks ago that one slightly irritating aspect of the Redfield Accu-Range reticle was that it was set up with nice round MOA dimensions, unlike the Bushnell that it replaced. I was looking through the scope again, now that it is mounted on the M1A, and I noticed something rather interesting.
The distance from the cross hair to the bottom of the circle is 2.19 MOA at 12x--not very useful--but the width of the crosshair lines in the circle is 0.19 MOA. What that means is that from the bottom of the horizontal crosshair to the inside of the circle at the bottom (or from the edge of the vertical crosshair to the circle at the left or right) is 2.00 MOA. This is actually a very useful number for rangefinding, because it simplifies the math. At 4x, according to their charge, this distance is 5.08 MOA (suggesting that something is lost in rounding).