The 9th Circus is the most liberal in the land. Hopefully the Supreme Court takes this case soon.
Even if they do, there are some old Supreme Court cases finding that Congress has the power to regulate guns if they, or any of their component parts, ever moved in interstate commerce. See Scarborough v. United States (1977) and Barrett v. United States (1976). Hard to say if today's SCOTUS would overrule those cases.