You need to understand that the Mil-Dot Master is a military tool, designed by Bruce Robinson (who was a long time woodchuck shooter).
It was first inspired by an Israeli sniper that Bruce knew. She needed some way to get faster ranges, and Bruce came up with the MDM.
A sniper knows the size of all the local items - the fire hydrants, the door frame size, the standard window size, the size of hub caps, and truck tyres, 55 gallon drums, etc... all within an inch or less. So when he is in position, he gets ranges from the local hot items, long before the target gets into view - rarely does he range on the victim, because people vary so much in hight and width. For ranging on the victim, the PSO-1 reticle is faster (but not more accurate).
The problem with ranging game is when you see an animal, how high from the ground to the back - is there grass, so you can't see the feet... and even if you could see the feet, exactly how tall is it?
The ability to use the MDM is directly related to your ability to know EXACTLY the size of the animal.
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