They will probably amend it to contain an assault weapons ban (IE a Semi Automatic Weapons ban)-With a turn it in requirement, a Cop killer bullet ban, and requirement of serialization-microstamping of all ammo... And it will be illegal to keep the old ammo.
One lawsuit -- just one -- about goobermint confiscation of property without recompense (and eminent domain does NOT apply here), and they'll find out that some judges at least still respect the Constitution.