As observed, the high quality Bernard I 'rough forged tubes' were sourced in Belgium.

At the time of First Obligatory (Provisional) Proof for “Double-Barreled Breech-Loading Sporting Guns” - breech plugged tubes - the tubes were marked with Script EL of Banc D'Epreuves Des Armes a Feu De Liege and a controller’s identification mark.

[Linked Image from photos.smugmug.com]

The bore was 15.6 = .614" = 20g; the muzzle was 15.2 = .598".

The 1.375 is the barrel weight in Kg at the time of final proof = 3.031 #. If the barrels weigh > 3% less now, they are considered out of proof by the Belgium Proof House.

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