In the full version of New World, it pays to keep your trusty musket loaded with cartridges and an inventory full of bullets. But to keep your bullet reserves high, you need a steady supply of Gunpowder, and for that, you need the raw material Saltpeter.
Like many useful items, Saltpeter is a mined resource in New World, meaning that you'll need a least a flint pickaxe to harvest it once you've tracked some down.
Depending on where you spawn into New Word, you will probably have to go out of your way to collect Saltpeter. Thankfully though, you get a good amount for every resource node you harvest - so it doesn't take too long to grind.
Where to find Saltpeter to make bullet cartridges in New World
In New World, Saltpeter spawns inside caves.
If you spawned near Monarch's Bluffs, there are two small caves to the south of the Hamlet you can loot for Saltpeter: Bayhowl Burrow and Hurtfang Hole.
Bayhowl Burrow Saltpeter
To get to Bayhowl Burrow, look to the southwest of Monarch's Bluff Hamlet. Then look for a rocky den that wolves spawn around, and inside you can find a Saltpeter node.
Hurtfang Hole Saltpeter
Hurtfang Hole is found to the southeast of Monarch's Bluff's Hamlet. Again, look for a rocky outcrop towards the north of the area where wolves spawn and you can find Saltpeter Nodes inside.
Or if you spawned into Windsward, there are two of these kinds of areas in easy reach in the early parts of your adventure. Namely: Torrentdawn Cave and Dankfur Hollow.
Torrentdawn Cave Saltpeter
When you first landed on Aeternum in Fury Bay, you were sent to defeat a Corrupted Chaplain in a cave.
Around the sides of the cave where you fought the mini-boss, you'll find some outcrops of Saltpeter.
You can find and return to Torrentdawn Cave with a short run back south from Windsward Village.
Dankfur Hollow Saltpeter
Probably a move convenient source of Saltpeter though, is Dankfur Hollow.
This cave system is found a little south of Windsward Village. Climb to the top of the hill and you should find an entrance to the inside area of the cave, where you can find some resource nodes to harvest.
How to turn Saltpeter into Gunpowder and make bullet cartridges in New World
Once you've got your Saltpeter in hand, return to a large settlement to turn it into Gunpowder. You can then use that to craft bullet cartridges to use as musket ammo.
Using Windsward Village as an example, on the southeastern side of the built-up area you can find a Workshop. This is where you craft new ranged weapons, as well as ammunition.
Scroll down first to Engineering components to craft Gunpowder, then back to the top for Iron Cartridges. You will also need some iron ignots for the casing and cloth for wadding.
If you're looking to make your own armor too, here's how to pad it out with cloth made from hemp fibers.
Or if you're the type who likes to brew their own potions, here's where to find petal cap in New World.
You'll also need RNG on your side when gathering - here's how you can farm the rare Fae Iron resource in New World.