to answer my own question - everything needed to calculate the MRAD for the various reticle features is in the Gemini reticle manual. I don't think I got a copy with my scope but I did discover it on the PA web site. the mrad or moa numbers aren't there but with a little math you can figure it out.
The key to the puzzle is the range finder on the bottom. the 36" distance at 100 yds was 207 pixels, meaning that 20.7 pixels equates to 1 mrad. I then measured the other features in pixels and converted to mrad.
tip of chevron to crotch of chevron: 0.75 mrad
tip of chevron to base of chevron: 1.35 mrad
tip of chevron to upper dot: 2.6 mrad
tip of chevron to lower dot: 4.8 mrad
tip of chevron to largest, upper range line: 10 mrad. ~300 yd shot with a 16" barrel 9mm
tip of chevron to lowest, smallest range line: 20 mrad
for the vertical range finder (36" target)
base to first line/200 yds = 5 mrad
base to 2nd line/150 yds = 6.7 mrad
base to 3rd line/100 yds = 10 mrad
the distance between the top/3rd line and the 2nd line is 3.3 mrad/300 yds to a 36" target
the distance between the 1st and 2nd line is 1.7 mrad for 600 yds. good luck shooting your 9mm at 600 yds
The base is 1.7 mrad wide, which would range an 18" horizontal target at 300 yds.
I could have made a mistake here and there, probably with mismeasuring the reticle graphic. an ms paint of all this would help a lot.
The PA rep should have pointed me to the gemini manual (which again didn't seem to come with my scope, I think I ordered a demo unit or something)