I would stay away from online schools...
Is he wanting to do this for a hobby or career?
There is a school in Colorado Trinidad I have always heard about.
But getting a apprentice with a good gunsmith would be a good option too.
I have thought about it before...
*need to be a machinists* the best always are...
Water
soy milk
yogurt
2 red bell peppers
leftover pasta
door full of condiments
not much,, I go to the store and get what I need for that meal. If not, I want to eat everything I bought.