“door to door” collections will result in a lot of dead folks.
I see a lot more problems with the idea of any door to door collection of guns than just the second amendment.
Illegal search and seizure (without probable cause, warrant), and confiscation of private property for starters, as well as the unpopularity of door to door searches that would be required from everyone since a lot/most of people would just claim they lost their weapons in that tragic rowboat accident.