The federal assault weapons and high capacity magazine ban is designed to alter the constitution and therefore should be put forth as a constitutional amendment. This would result in the ban becoming more difficult to pass, but it would be permanent and no state could contest it without proposing a new amendment.
Article V of the constitution requires that ammendments be passed by:
1) two thirds of the Senate
2) two thirds of the House of Representatives
3) three quarters of the state legislatures.
If any of these are NOT met then the attempt to amend the constitution would fail.
I do not support criminals with guns, but I do support my right to bear arms. If it is going to be taken away I want it done correctly as intended by our founding fathers.