Forgotten Weapons's Ian has a candid writing on the reality of making love of firearms in to a career. It's one of the most realistic advice one can see on the subject. One can take the route of a machinist or keep firearms as a hoby while as working in unrelated field.
It's a bit long for average internet reading, but definitely worth to do so.
Link: http://www.forgottenweapons.com/how-to-become-a-professional-gun-nerd/
From: Forgotten Weapons
