All lost, and stolen guns must be reported to the federal and local government. This means everyone will have to fill out the theft/loss form, and not just FFLs. You only have 24 hours to comply. If you lose a gun on a hunting trip deep in the woods, and cant get back home to fill out the form in 24 hours, youre a felon and will spend 5 years in federal prison. And teaching someone to shoot on your own land is a felony, 5 years, if you hand them the gun. Not an exempted transfer.
Full Text of S. 374: Fix Gun Checks Act of 2013 - GovTrack.us
Full Text of S. 374: Fix Gun Checks Act of 2013 - GovTrack.us