Ordnance Optical Scope Questions

I've been shooting since I was 10, am 74 now and bought my first scoped rifle to play with. It's an '03 Springfield that's been sporterized (which I consider ruining the rifle) and has an Ordnance Optical 4 X 32 scope on it. The number 307960 is on the data plate along with their Culver City, CA location.

I have the following questions about the scope:
1. Are the graduations in MOA, or one of the other measurements?
2. Is there anything to the story I have heard about needing to thump the scope or fire a couple of rounds to "settle" the adjustment mechanisms after making an adjustment?

I have tried searching for information on it online, but everyone seems to only want to talk about the O. O. scope that Lee Harvey Oswald had.

Thanks!