I spent some time looking at French sites for info on Massardier. I can't find much without going into French genealogy sites and paying out some francs (Euros). The only reference which may be of relevance is the 24 Sep 1885 death notice of Marie Poulat, 48 years old, wife of Jean-Baptiste Massardier, "Armurier", rue Villeboeuf, 48, Saint-Etienne.
Looking at Jean Baptiste Massardier, he apparently had children by two other women;
-- 1878 death notice of Marie-Louise, 8 months old, daughter of Jean-Baptiste Massardier, armurier, rue du Vernay, 6, and of Antoinette Vuldy.
-- 1884, Jean, two years old, son of Jean-Baptiste Massardier, armurier, and of Marie Laval, rue de la Barre, 5, Saint-Etienne
There's nothing much to report from the two addresses, rue de Vernay or, rue de la Barre.
Massardier is a fairly common Stephanois name. There looks to be at least two. Here is another:
-- Jean-Baptiste Massardier, born 21 Aug 1833, Saint-Etienne, Loire, Rhone-Alps, Valbenoite. 1860 married Louise Gouilloux; - four children.
Strange that there's nothing at all on Passionlachasse.fr. Perhaps he only made a few guns?
As for Coirier, there is a Claude Jean Baptiste Coirier, Arquabusier (gun maker) who took out a patent in 1865 - but this was done in the Department of the Seine, however - maybe that's where all patents were registered?
