Repealing the Second is a necessary, but not sufficient, condition. It should be followed up by passing and enforcement of restrictive gun legislation. No grandfather clauses, you have 120 days to obtain a license or your guns will be seized.

American gun owners are like Arch Linux users: you know who they are because they'll tell you. They might clam up after the gun laws pass, but the FBI and ATF will still know where to conduct raids to nab a few high-profile targets.