Determining original choke constriction

[Jeff S.]

Shame, shame on me. Some of you gentlemen were kind enough to offer input, but I haven't been on the forum for a while so I probably appear rude. Please forgive me.
The serial # of my gun is 151643. It's not one of those "minty" original guns. It's been refurbished, looks great (to me) and I like the way it handles. Both barrels have .015" of constriction. According to the letter that I received from Chuck Bishop (June 6, 2017) the right hand barrel should shoot a wider pattern than the left. Based on the information in the letter, we can all assume that the left barrel has been "opened up".
A logical assumption for a Parker "newbie"such as myself would be that it shipped from the factory choked "mod" and "full" (the letter states 125 pellets right and 170 pellets left). I simply wanted to start learning a little more about Parker's patterning tests. It was suggested that Parker used 1 oz loads of 7 1/2 shot which would mean roughly 345 bb's per load. If that was the case, Parker must have used a circle smaller than 30", or a distance greater than 40 yards.