MP;
I recall you having posted this before & is extremely good. I did question you before about the wt difference & know you said was by actual wt, but all else being equal one would expect a finer granulated powder to weigh more than a coarser one. Industry standard for a black powder measure is based on .115 CuIn per dram (27.34 grains). A CuIn of water weighs @ 253 grs, so the .115 CuIn would weigh 29.095 grs. This gives the dram of BP a density of 94%. A chart I copied off from somewhere many years ago, signed by Homer Powley, gave average bulk densities of a variety of smokeless powders as well as BP. It in fact listed 2FG Black as having a density of 94%, with 3Fg @ 98% & 4FG @ 100% so would seem the industry standard was based on 2FG. Black powder weights will of course vary a small amount from actual lot to lot. I cannot help but believe the lots you weighed varied in the man'f, perhaps a heavier wood for the charcoal etc, which caused the 2F to weigh more than the 3F rather than the granulation itself. Never-the-less this is still the best read I have ever seen upon black powder use IMO.
I’m retired now so I don’t have the time to redo the test but if anyone cares to undertake this and if you find that FFF weighs more than FF per same volume I’ll amend my notes.
