3" GHE

[jeffery c]

I measured my 12 gauges at the barrel/forcing cone and weighed them with the following results:
Baker Paragon L-.97, R-.103 weighs 3# 13 oz. 2 5/8" chamber
Win 21 L-.115, R-.119 weighs 3# 9 oz. 2 3/4" chamber
LC Smith Field L .102, R .105 weighs 3# 15 oz. 2 3/4" chamber
Parker PH L .107 R .115 weighs 4# 1 oz. 2 1/2" chamber, 1 frame
Parker VH L .90, R .90 weighs 3# 4 oz. 2 5/8" chamber, 1 1/2 frame
Parker GHE L .96 R .104 weighs 3# 10 3" chamber, 2 frame

These are original finish and bores, I'm pretty certain. All are 30" except for the VH which is 28".

Can anyone help me out with these dimensions or even outside contour diameters of a factory 3" or 2 7/8"? The GHE doesn't have records to say one way or the other as to whether the chamber was done at the factory. It seems unlikely the 3" chamber is original, but I'm curious as to the contour of a confirmed and lettered long chamber gun.

Are these thicknesses typical in your opinion?