Too, streamline things a bit, you'll need cutting tools like saws. slicing tools, like chisels and planes, and abrading tools like scrapers and rasps or files.
Griping tools like a vise, vise grips, clamps etc. will also be required.
Within each of these genreal catagories is a whole range of things you can equip yourself with. Each new effort will somehow require a new tool. Right now I'm having best luck working my GPR kit using a half-round 1/2-inch Buck Brothers carpenters gouge and No 7 and No 3 wood carving gouges. I know if I were to get more elaborate with the project, or start an altogether new project I'd probably get better results using something else. At Benning School for Boys, the standard answer to every question was "It depends on the situation." That's pretty much what you're going to arrive at when you try to decide what tools you're going to need for a particular effort.
Just buy some basic ones and go from there. If you have to stop a project to wait on a new, but correct tool to arrive, do it. You're number one tool is patience. You're number two tool is the ability to visualize the project in 3D and to extend your vision so as to see how one thing might lead to another. This will keep you out of trouble.
Add to your gunmaking library the book, "The Nature and Art of Workmanship," by David Pye. It's a good mind tool.