Mercenary,
You're aware that filling out the DOJ Form 4473 when buying a gun at a dealer does NOT officially* register it, right?
If you're aware of this, good for you- no offense intended. I ask this because many "how do I register my gun" threads are rooted in misunderstandings about the nature and purpose of the Form 4473. It is nominally intended for FFL record-keeping, NOT for any type of official registration.*
*YMMV depending on the tightness of your tinfoil hat. 