its not about blackpowder but amazing "Making Aspirin into Picric Acid (TNP)" https://www.youtube.com/watch?v=BmAW7U4a89U

picrid acid was the first explosive that was insensitive enough to works in artillery grenades https://en.wikipedia.org/wiki/Picric_acid

until then grenades were filled with black powder.
also in WW 1 sometimes grenades were filled with blackpowder when no other was available. I know the turks used blackpowder grenades at gallipoli when no better was at hand.
various test with TNT/dynamit sometimes work sometimes explode in the barrel and pricid acid make the way for artillery grenades with high explosive stuff.

making such stuff from asprin pills is a funny way