Here is a very interesting article in French on French gun-makers in Paris in the 19th century.
http://chrisferon.free.fr/blog-articles/paris-ancienne-capitale-armurerie.php

Here is a Leopold Bernard barrel with the French Parisian proof-house stamps along with the bore size. This is what should be on the gun.

[Linked Image from i.imgur.com]


Baluch are not Brahui, Brahui are Baluch