This answer is posted a half-dozen times in this thread. Do you really think they don't already have the data at hand to figure this out?
Have you ever bought .223 rounds with a credit card? How about a sight or a trigger or a grip online? Or even googled AR parts?
There is already a database query written that could generate a list of 95% of the people who own ARs in a couple of seconds. The government just hasn't decided to do anything with it yet. I think people already forgot what Ed Snowden revealed about our government.
This all sounds paranoid, but it doesn’t mean it’s not true. ;-).
Im old enough to remember when people freaked out because they thought cell phones *might* be able to be used as a locator for a person. Cell companies of course put our minds at ease...
Now we have apps and “find friends” and OnX maps that tell us where we are to the yard...and we pay 100$ a month for that...