In NY they will do this very gradually.
Whenever you are stopped for anything by the police, they will check to see if you bought an “assault weapon”, and try to enforce the SAFE act.
Whenever you do anything related to taxes or vehicle registration, they will check.
Any interaction with the state will result in a check regarding “assault weapons”.
They will probably do things like deny vehicle registrations until you turn in your illegal weapons, or satisfy them about your weapons.
It will be a very gradual process, not an all at once move.
“It will be a very gradual process, not an all at once move.”
I met an investor who sold is business and moved out of New York. He said, “I’m not giving up my guns.” So, he moved his sizable fortune to Florida where he’s busy buying property here instead of there.
They gave a year to sell, destroy or register the weapons. Now they did make the sale/transfer within NY immediately prohibited.
However, pretty simple solution to that really...
“No, officer I no longer possess the weapon, I sold it out of my car truck to a Vermonter when I was at my buddies camp in Vermont. The leaves were turn, it was beautiful that weekend. Have you been to Vermont.”
-or-
“Hey, I left it at my buddies camp in PA.”
Point being it’s not illegal for a New York State resident to transfer and/or possess an “assault weapon” outside of New York and the enforcement arm within New York has no jurisdiction in any of these places. (In other words “piss off”.)