GUNS DON'T KILL PEOPLE, OR DO THEY?

[F.U.]

If guns change hands legally then there is a record of it.

Yes there is technically a record of it, but that record is stored in the gunshop where the transfer was made. The ATF never sees that record. The background check that is done through NICS is wiped clean at the end of every day. Or at least it is suppose to be. Plus all they do is check to see if that person can legally own a firearm, not what the firearm is.
So really no there is no real record of who owns what.