The lettre annale is for 1928 Rob.

The tubes were supplied by Jean-Baptiste Delcour-Dupont/Canons Delcour S.A. (barrel production) of Nessonvaux. They weighed 1.346 Kg at the time of proof. If > 3% less now they are considered out of proof. The bore at proof was the usual 18.4 mm = .724".

It is very common for Liege guns produced for U.S. export to carry the chamber length in both mm and inches.

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