Wait, how to make gunpowder from what? Is that even possible? Well it turns out that making gunpowder out of urine—and a number of other ingredients—is possible, if in a complicated and roundabout way. In fact, it even kind of makes sense. After all, in a post-apocalyptic world where ammo is scarce, urine is one of the most nonrenewable resources at your disposable. Time to start saving up that brass…

Yet how does this work? Is pee inherently explosive? Well not exactly.

Consider it this way: gunpowder is made out of three quarters potassium nitrate, a sprinkling of charcoal, and a dash of sulfur. Charcoal and sulfur is relatively easy to obtain, but potassium nitrate? You’ll be hard pressed to find that in nature. That’s where the urine comes in, but it doesn’t turn into potassium nitrate overnight. Instead, urine can be used along with ash, straw, and manure into create a mixture the can eventually be filtered and ground. It’s a fairly time-consuming process, but the technique, also called the French method, is actually pretty well-known.

Brace yourself, you’re about to get a hefty dose of science.

Image screenshot of video by Cody'sLab on YouTube