You do not have a semi-automatic assault rifle.
Call it whatever you want. I’ve owned my FAL and two mini-14s for many years and run a lot of ammo through them all. If you want to define “assault” as full auto rock and roll...fine. I understand it and cen accept it. But, I will still call my FAL by that name, that definition notwithstanding.
Unfortunately, NY State, in passing its on "Assault Weapons" law, latched on to the false Federal definition (created by Feinstein et al. in 1994) as to what constitutes an "assault weapon" (a weapon manufactured after Sep. 1994 and having more than 2 "evil" features, as far as rifles are concerned), so technically, if this guy had a non-compliant rifle, he possessed an illegal "assault weapon", even if it was only a semi-auto rifle.
“You do not have a semi-automatic assault rifle.”
Having witnessed the rapid breakdown of a normal society with my own eyes, I would say that every law-abiding citizen should have at least one semi-auto weapon and plenty of ammo on hand.