This revolver Has: Mre d'Armes St Etienne engraved on it. On the barrel it has Mle 1892 and S 1901. There is also An L and a B both have circles around them. I would like to know the caliber and is ammo still available? There is fairly strong rifling but also quite a bit of pitting. Would it be foolish to try to fire it? What it's worth?