Lots of ways to accomplish that over time.
Offer wives thinking of divorce a bounty to let cops seize hubby's guns while he's at work, then arrest him as he arrives home. Offer kids a bounty to turn in their parents next time they're mad at them(or a get out of jail option the next time they're arrested for drugs or driving drunk) . If there's ever a fire at your place, and somebody finds a gun in the burnt house afterwards, you are arrested.
Incoming state level GVRO laws aka Red Flag are intended to do exactly that. Angry spouse or liberal neighbor whines to nearest po-po, “He threatened me, he has guns, and I’m afraid for my life”.
Po-po goes to (liberal) judge, a GVRO is issued, and with no notice or input from said gun owner, the po-po show up at his doorstep & it’s over. Forget about ever getting them back.
I hope your angle about po-po offering bounties to denounce gun owners doesn’t become law. But it could. Scary.
Leave it to you to drag evil divorcing womyn into the argument, lol!