I would also point out that there is no Article I, Section 8 power authorizing the general government to ban any firearm (or infringe the right to keep and bear arms in any way).
The anti-Federalists were afraid that the Bill of Rights would be misunderstood as prohibiting actions which the general government has no power to do. And that by repealing the BoR (or any of its articles), this would be understood as "authorzing" the government to infringe our rights.
Repealing the 2nd Amendment doesn't authorize the government to ban firearms. The only thing that protects our right to keep and bear arms is our willingness to use them, if any tyrant should try to disarm us.