Ferdinand Claudin
célèbre famille d’armuriers du 38 boulevard des italiens à Paris.
Made around 1850 ?
There will be further marks inside the lock.
With this calibre, a "4 GAUGE", this is a big game hunting gun.
Two things surprise me Jean-Luc; your taste for such 'vulgar' pieces and how you manage to measure the bore with the pied a coulisse in that position ... like reading 16,9 mm

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