After the SS Grandcamp exploded, causing the Texas City Disaster, it has been all but impossible to find 34-0-0 in the Houston/Galveston area.
There is still bug repellent, Bar-b-que fuel and a meat preservative.
Or the old fall back position of (a certain common potassium chemical) boiled with table sugar!
BOOKS you may want while reading ain’t illegal yet!
Foxfire 5. Iron making, gunsmithing (and gunpowder making). Edited by Elliot Wigginton
A History of Greek Fire and Gunpowder. Johns Hopkins
3001 Questions and answers by A A Harding (Fur Fish and Game magazine publications.