To paraphrase a line from the movie Crash,
"people will turn in whole guns because they didn't see it coming, and were not prepared. Some of these people, might be sitting on their couch, watching a live in the making documentary about gun seizures, when they get the knock on the door, and even still they won't be prepared."
When the police get there, it will be too late. The will not let you strip your gun in front of them just to have over the receiver. Most people don't even that the tools to strip a long gun nor the knowledge to strip their semis down to the bone.
I personally don't think the LIberals will ever successfully create the legislation to enact a ban, let alone spend the real money to enforce it. But if they do, I will be prepared.