Via email from Ry is this web page on experiments with both black powder and smokeless powder where the experimenter fails to get ignition of gun powder with static electricity.
I wouldn’t count on static electricity not igniting the powder but if you were hoping to use it as an ignition source you probably would be disappointed.
I seem to recall that one of the final processes in making black powder is to coat the granules with graphite, which would give them a pretty good conductive shield. It would be interesting to try this with the output of a photoflash pack. And if some black powder were to turn up right next to an old-style flashbulb, I’m pretty sure it would go right up.