Sorry I was not paying attention, but that sneak Raimey already added images to the proof marks thread
It was manufactured by
Manufacture Liegeoise d' Armes a Feu For a shop or dealer named Louis Rerle'
Despite the very odd 75mm chambers, the load indicated is 1.68 grams = 26 grains of a 33 grain bulk powder = 2 1/4 Dr. Eq. with 21 grams = 3/4 oz. shot, and that is what I would use.
And here it is
http://www.shotgunworld.com/bbs/viewtopic.php?f=5&t=182949 And since it is at least 110 years old, it deserves an evaluation by a doublegun specialist before use,
especially careful measurements of the wall thickness at the end of those long chambers and into the forcing cones.
