Superfine BP ?

[OB One]

I found this almost full can of Dupont superfine black rifle powder. The label says it is suitable for muskets, pistols, and shotguns.
I'm out of powder except for this can and a 1 lb can full of 777. What might you say this superfine is equivalent to, 2f or 3 f?

 

[Whitworth]

My old DuPont can marked like yours has FFFg on it, my brother has one marked FFg so it looks like grain size is indicated. I believe the "Superfine" refers to quality, not granulation. YMMV

 

[ord sgt]

Since it is stated "for muskets, pistols and shotguns", you have what I believe is FFg equivalent. It should be a coarser grain than FFFg.
Just be 100% sure that you have black powder, and not smokeless powder.

 

[SDSmlf]

DuPont and then GO used to label their powder ‘SUPERFINE’. The granulation will also be noted. The mention of using 4F as ‘suitable for muskets, pistols, and shotguns’ as listed on the container by the manufacturer will cause some folk’s hair to spontaneously combust, though others and myself have used it as intended for decades without issue, you just have to adjust your powder charge when changing granulations for consistent performance.

 

[necchi]

I believe the "Superfine" refers to quality, not granulation. YMMV

Your right, "Superfine" was really just a marketing gimmick,, a "label" on the can of Dupont powder,, aka: the good stuff.
There should be other markings on the can to denote granulation,,
p.s. SDSmlf beat me too it,