Are the original barrels unusable or missing?
If you have the originals, are they marked in mm, and if so, what are they marked?
Do the chambers measure 2" and how did you measure them?
What is the date code on the barrel flats?
Does the catalog repro show the grade?

Kyrie: during what period was the chamber marked c.410.50 ? Thank you.
Shotgun chamber in Spanish is recámara; in Basque ganbera
Barrels in Spanish cañones

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