The saddest part is that the powder from fireworks isn’t the preferred explosive for a pressure cooker bomb. One of the counter terrorism experts I saw on the news yesterday said that match heads are proffered.
They burn more slowly but build up considerably more pressure and make a much bigger boom.
When I was a kid we used to pack matchheads into a BB gun CO2 container light a fuse and get the he!! away.
Amazing how big the explosion was.
That's what the AQ Chef recommends. He also gives helpful hints, such as to avoid "having any of the substance on the treads [sic] of the pipe so that it won’t ignite when closing the pipe" (might cause a work accident). He mostly describes pipes, although he does give passing mention to pressure cookers, fire extinguishers, and propane canisters as other suitable bomb casings. And he also lists gunpowder and "the powder from fireworks" as suitable "inflammable substances".
The AQ Chef is believed to be the late New Mexico-born Mooselimb cleric Anwar Al-Awlaki (killed by a Hellfire missile launched by a guy sitting in an office chair).