Spent some of my miss spent yoof making gunpowder with a friend of mine (he still is)
First year high school, serious case of boredom and Wow.....off to the hardware store, buy sulphur and saltpeter in 1 pound bags, grab all the charcoal out of the fireplace, mix it together, spread on a baking tray and dry it in his Nan's oven (luckily his Nan had an electric oven) and then use it to launch marbles out of various size pipes just to see how much damage they would do or how far they would go.
We spent quite a few weekends engaged in this activity
PS. Mum had a copper copper when we first came back to Melbourne in the sixties. Heated by a gas burner
And yes, she had a copper stick as well (ex broom handle)