thanks. perhaps I didn't make myself clear. each of my guns is what it is. I use whichever one I feel like using, with the knowledge of how it actually shoots, not what is marked on it or what it reads on the bore gauge.

I was just curious why the choke markings and choke charts are so often way off the mark from the way guns actually pattern. From some of your responses I guess the way the choke is cut, the angle and length of taper can make a difference. I have to think that way back with black powder and using wads instead of shot cups it was also very different. I would guess the patterns were some what wider.