I'm fairly certain it is a true mil. I have the MilRad version, and when I set up a mildot confidence target, the diamonds were dead-on 3.6". There are hash marks at .5 mils.
According to their site, even the standard 20x mil-dots are true mils:
And the Mil-Rad version:
I could be wrong though... in fact it happens more than I'd like to admit.
Also, what program did you use to get the drop on that mil-dot? It's pretty clean-looking.
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