[Fido969]

something very simple like smokeless black powder, a low-order explosive ... but enough to do the job in a big crowd."

Smokeless powder and black powder are two different things.

I was surprised at what I thought was a limited amount of smoke at the explosion, I know you can make a bomb out of black powder, can you make a bomb out of smokeless powder?

[E. Pluribus Unum]

I was surprised at what I thought was a limited amount of smoke at the explosion, I know you can make a bomb out of black powder, can you make a bomb out of smokeless powder? The "bomb" was the pressure cooker, and anything that would burn and build up pressure fast would work to turn it into a bomb.

[Hardraade]

Standard gunpowder is smokeless, and all it takes for a pipe bomb is a pipe, a blasting cap and a fuse.

Blackpowder (the real kind) is highly dangerous, explodes at a tiny spark or if you look at it sideways and basically requires just a bit of fuse.

People have blown themselves up just screwing the top on a pipe with that stuff.