[Lurkinanloomin]

What they are really doing is making private sales and transfers illegal so that there will be a record of all transfers so they can build a registry.

Registration is a required step towards confiscation.

[Myrddin]

There is already a defacto registry in the Form 4473 records in "bound books" at each FFL. ATF can inspect anytime they wish. Recently, Form 4473 was revised to move the type, manufacturer, model number, caliber information off of page 3 to the top of page 1 of the 4473. An optical scan of just page 1 provides everything needed to efficiently "register" a firearm to a purchaser.

Private sales between individuals don't require an FFL to do paperwork on the "transfer" in many states. The net result is that the "defacto" registration validity rots over time as the paperwork trail evaporates.