Not as good as Geoff's image, but better

[Linked Image from photos.smugmug.com]

Original Birmingham Proof 1925-1954 at 3 Tons = max. service load about 9000 psi
13/1 bore .719 - .728" and at reproof as greybeard said .736"

Can't explain 2 Birmingham reproof date codes, but some alteration in the barrel had to have been made.

I don't know what the M over 928 means?

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