I do not know if what I do is the right way or not but this is what I got

Hand flipping as hard as I could 8 times

Stock ring about 65 PSI
Bowman ring 85 PSI

Turning engine with a electric starter

Stock rings 95 PSI
Bowman rings 120 PSI

As for the post about pre breaking in rings, There is a little more to Bowman rings than breaking in, They have a better ring gap and with stock ring they will even have a bigger gap after they are broken in.

Milton