Quote:
Originally Posted by Mr_Draco
False.
Per ATF laws AR-15 lowers MUST be registered with the ATF at the time it is purchased from a FFL holder. A AR-15 lower must be treated identically to a rifle or handgun in this regard.
The only exception to this is if you purchase a blank lower that did not go through the final machining process of the manufacturer. They look like this. 
After you complete the lower you do not have to register it as long as it remains under your ownership. If the gun passes down to a son (like after you pass away), or is intended to be traded or sold then you are required to put a serial number on it and register the lower. |
There is no national registry for any firearms other than NFA examples. Some states require certain firearms to be registered but it's generally pistols.