My question was sincere. I'm quite sure that some share of the guns would be vol...

My question was sincere. I'm quite sure that some share of the guns would be voluntarily handed over. I was after a estimate on this share.

"Collecting all the guns in the US won't be an easy task."

Definitely not, but I would think that to be something an oppressive government would try to do. In that case, the police might not ask nicely.