In the 1700s gunsmiths used a boring bench, a rifling bench, and a pan borer which was made for gunsmiths.
Guns were simpler then, but the tools needed have not changed that much.
They were often using blacksmith tools.
They used metal files, vises, drills, and augers to work on the simple guns that were available at the time.
They also needed some woodworking tools and skills for the stocks.