S. 374, the so-called "background check" bill would criminalize all kinds of innocent actions that don't currently count as a transfer. In fact, as a gunowner, unless you never let any living soul touch your guns and kept it locked in a container only you had access to, it would be almost impossible not to become a felon under this law.
Leave your spouse with your pistol for more than 7 days while you are out of town? You're a felon.
Loan a rifle to your buddy while you are hunting on public land? You're a felon.
Drive over to your buddy's house to show him your latest gun shop treasure from the consignment rack? Felon.
There are so any problems with the law as written, you couldn't cover them all in a law review article. This is about way more than just "background checks." Difficult to believe that a Senator who has been writing anti-gun legislation for 20 years did all that accidentally.