I did some more measuring after work. Sorry, I should have taken more time this morning. I don't know if this will make a difference or not.
The chambers taper .004"/inch for the first 2 3/4".
At 2 3/4" the taper increases to .024"/inch until my gauge bottoms out at about 4 1/4 ".
Maybe it is just a standard forcing cone job and my flat Galazan gauge is misleading me.
terc