GH Barrel Flat marking

[winplumber]

I have a Gh with out the + gun # 65517 which I think is factory bored over nominal Its a number 1 frame and good wall thickness.

[Joe D.]

I just measured the bores. Left bore is .731 with .695 at the muzzle. Right bore is .731 with .695 at the muzzle. Minimum barrel wall thickness is .034 Left, .036 right. Isn't .731 fairly normal? Thanks. Joe

[Pa SxS]

Prior to about the S/N range of 60k, the 12ga bore diameter could range from about .745 to .760. I have yet to measure a 12ga bore on later guns that were at the standard of .729. Most seem to be .731 to .735.