Good on you, Oz. I lose a few relatives every year to gunshot wounds. I used to be the back-up for our medic "back in the day"* HMC Ho picked me because he saw I was reading a scifi novel. (Starship Troopers.) "I'll take him because he can READ. You goons..."*
I picked a dude who admitted to having never fired a HMG. Nothing for him to unlearn. Tabula rasa is a good route to a good gunner.
*When we first met as a group we had a ◊◊◊◊◊◊◊◊ session (I mean "familiarization meeting" of course) where the guys stated their "extracricular quilifications" One chap was a genius at ad hoc repairs. Introduced so at that meeting by the LT. Our corpsman was first to pick as we all considered his job most important. ("Keep my ass alive, hell yell, Ho, pick carefully!" Also because I didn't puke at the sight of blood. Yeah, them boys weren't all that familiar with family-level combat. Must have been nice.)