What will happen is a slow incrementalism intended to leach the firearms out of the most armed citizenry anywhere. It is happening: environmental restrictions against lead ammunition, zoning regulations intended to make possession of firearms in urban and suburban areas impossible, attempts to stretch terrorism laws to cover domestic disarmament. That's what we have to watch for, IMHO.
The Liberator was meant to be an assassination weapon. Close range, high-value or engagement-critical, targets.
I remember reading that the last lead production mine was shut down under Obama. If so, by denying ammunition the government will eventually render firearms useless.