In the 17th century, Joseon tried to produce gunpowder, but due to the lack of gunpowder production due to the rainy season, only small cannons could be used.
Europe used huge cannons, and how many gunpowder did Europe produce in a year in the 17th century?
While there will always be more to be said, I summarized the basic outlines of late medieval/ early modern gunpowder production and raw material trades before in: Where did the original raw materials for gunpowder (black power?) come from, together with the more excellent answer by /u/ParallelPain, including on saltpeter recipes from early modern Japan.