After all this discussion, I measured all 4 of my doubles and an old Iver Johnson single shot 12 gauge.

I have the forcing cone reamer and the gage to check before and after.

Here is what I found. The Fox Sterlingwortth, 1931 vintage, Ithaca double, 1936 Vintage ,Iver Johnson, (At least as old) and an older pre 1900 Raick Freres Belgium double all have the identical chamber length to the forcing cone for a 2 /1/2" shell. Another Fox double,which I rebarrled with Brownell's barrels sometime in the late 80's also has the same length.
What I don't know and cannot measure is the angle of the forcing cone or it's length.Gues I will leave them all alone.

Last edited by saddlesore; 01/11/11 06:59 PM.