It wouldn't make a difference if they did somehow manage to pass some gun grabbing bill
You'd have cops getting shot and killed en masse trying to take guns, if they even bother to try because they know that's a nightmare scenario
Imagine this, you're a cop, you've been told you need to start rounding up guns. You have to go the house of a legal gun owner who knows you're coming for their guns and you have to knock on their door and... do what? Search the house for their guns? Ask them to hand them over? It's literally unenforceable. The only thing it'd do, if anything, is ban sales, and honestly I hope they do, because then just like abortion you handicaps are going to learn what happens when you start acting a little too stupid for the average person to follow