The big thing these days seems to be building your own firearm. Can you do this?
Yes (most places in the U.S.), and its not particularly hard. But there are some caveats. My series on this, using the AR-15 as an example, has been submitted for publication, and I will update this with the links when available.
Part 3 (Lower parts): http://www.theprepperjournal.com/2017/04/27/building-firearm-part-3-ar-15-lower-parts/
Part 4 (Upper parts): http://www.theprepperjournal.com/2017/05/08/building-firearm-part-4-ar-15-upper-parts/
Part 5 (“Manufacturing” the receiver):
Part 6 (Assembly and Results):
My recommendation for your first build is to get a complete upper pre-built. I have written another article on how to build an upper for “advanced” builders, but don’t know where it will be published yet.