[Ryu-Kazuki]

This is, intended to be an easy solution, and way to provide easier access to (certain) guns in the game, this way Gunners don't have to have a heart attack trying to find something decent to use before either getting an arena weapon or something.

Crafting Book: Guidebook to Guns

Guns in the book:

Handgun (1)
5 Ore
1 Gunpowder

Autopistol (2)
5 Ore
1 Gunpowder
1 Empty Mana Crystal

Shotgun (2)
10 Ore
1 Gunpowder
1 Geode

Rifle (2) (A basic, non-excel, rifle. It could probably just use the icon, or as a placeholder until it gets a better one. Increases crit by 10.)
10 Ore
1 Gunpowder
1 Tuning Crystal

Crafting Type: Metalwork

Constant Required Material: Gunpowder

Now, guns, can be powerful weapons, and their specialty is to bypass defense. They still won't be able to be upgraded at a blacksmith, but just acquired in an easier way than now. If guns become craftable, they should be limited to one positive quality. So basically, only one of, Sharp, Precise, Deadly, or Lightweight.

This suggestion is mainly, to make basic types of guns, easier to acquire for gunners. All the fancy stuff, go find in a dungeon.

[Trexmaster]

If you want them to be limited in how many qualities they could have, you could just make the difficulty higher. It'd make sense, I think, since making a gun is a world of difference than a sword.

All this really leaves though is excel rifles and magical novas to be found in dungeons gun-wise (curses non-withstanding).

I wouldn't call the Autopistol a basic type of gun.

[Ryu-Kazuki]

Those would be the difficulty without ore type applying. Meaning it still increases, and unlike other weapons you can't increase skull when crafting them. So a basic handgun at max would require 3 skill in the craft, and that's plenty for a basic weapon / starting craftsman.

Also you're forgetting Hold-Uppers, and Yin/Yangs.