I don't wan't to cause angst here, but "choke" is a matter of the amount of constriction from the bore to the reduced part of the barrel at the muzzles.
What I'm trying to say is, there is a lot of variance from one gun to another, and the true determination of physical choke is from back in the bore, then the difference at muzzles or the couple of inches ending at muzzle.
All I am saying here, is a bore gauge that measures in 1000ths of an inch is more accurate than a "plug."
Also, measuring is only a rough estimate of patterning. If you REALLY want to see what it does, shoot it at a pattern board.
Sam Ogle
