Sheepdogs, the self appointed defenders of the general population? (Not to be confused with LEOs and the Military, who are paid and sworn to the job.)
AD = Accidental discharge.
Castle Doctrine = One's home is one's "castle". You come in unbidden, you are a legitimate target, with no frivolous legal repercussions. (Often referred to as the "Make my day!" Law. Facitiously, of course.)
GG = "Good Guys"! (Not to be confused with my usual "signature".)
RSO = Range Safety Officer
AG, A2A = "Anti Gunners", "Anti 2nd Ammendment"
Hopliphobes/Gunaphobes = Lit. Those afraid of guns/weapons. Sometimes feigned, sometimes legit. Always used with disdain for those affected.
Just a few to add to the lexiconography.
GG