Potash

The Potash (pot - ash) mod uses real-world science to let the player craft gunpowder. It adds a new block and item called Potash, this is a real-world thing that is used to make real-world gunpowder. The in-game steps mirror the real-world steps by putting charcoal in a brewing stand and brewing it into a water bucket to get Ashy Water, after that place the Ashy Water then leave it and wait (about 10 seconds) for the water to "evaporate" leaving you with the Potash block. You can then use Potash to make gunpowder by combining it with charcoal, and bonemeal again very similar to the real world.

More is on its way for this mod, the realistic craftable gunpowder is just the beginning.

This is a Forge mod