Distance = (size of target in inches) divided by (MOA reading) times (100) times (.955)
This is what I got for your's:
moa | size/moa*100 | *.955
5............200...........191
3.2.........313...........298
2.5.........400...........382
2............500...........478
1.6.........625...........597
1.5.........667...........637
1.2.........833...........796
If your scope was SMOA (Shooters Minute of Angle) instead of MOA (Minute of Angle) you would't have to multiply by the .955
You can practice this interactively on Horus Vision's website - remember their ranging reticle is SMOA not MOA. For your's you'd still have to multiply by .955
Here's the link:
http://horusvision.com/img/hrsgame.swf