Usually grams. Here is a 20g; 1.68 grams "poudre" = 26 grains of a 33 grain bulk powder = 2 1/4 Dram Equivalent; 21 grams "plombs" = 3/4 oz. shot
A 12g Manufacture Liegeoise likely proved with Mullerite for a service load of 2.70 grams = 41.67 grains = 3 Dr. Eq. (42 grains) "E.C." No. 1 or "Schultze" with 36 grams = 1 1/4 oz. shot
BUT here is a 12g S. Bougnet for William Read with a Max. service load of 33
grains of "E.C." No. 3 = 3 Dram, with 1 1/8
oz. shot.
and a Demoulin Frères & Cie 16g in 28
grains = 2 1/2 Dr.Eq. and 7/8
oz.
