To follow up on the handgun -> FFL thing, could you run into trouble in the future for not doing so? Say for example, one of the handguns gets sold, lost, stolen, etc. or for whatever reason not in your possession. For the sake of this argument lets say sold and an ownership trace is run. Even without a paper trail let say the guy remembers who sold it to him (you) and you get contacted, but the last FFL record shows sold to your relative in TX. How do you explain having possession of the gun?
Well, we could generate all sorts of "what if" scenarios in which problems could arise. But yes, any investigation in which firearms are involved COULD result in legal problems. How much and what kind of legal problems depends on the situation.
Let's take a scenario like what you described and spin it a couple different ways.
Way 1:
Texas relative owned the handgun for 5 years and gave you the handgun last year. You took the handgun home to NC, where you have been a resident for the last decade. Let's say that you were pulled over for a traffic violation and you were carrying that handgun as your CCW. Through the course of the interaction the officer relieves you of your weapon and as he's processing the traffic violation, he runs a check on the handgun and it comes back as stolen. An investigation is commenced over the next several days and the firearm is traced back from you, to the point where you received the firearm from your family member a year earlier, and your family member accounts for it back to the point where he bought it five years previously at a pawn shop.
Nothing in the investigation leads the detectives conducting the investigation to believe there were any criminal ties to the original theft. However, during the course of the investigation, they discover the transaction between yourself and your Texas relative did NOT involve a transfer of the handgun through an FFL as required by federal law. Criminal charges could very well be forthcoming for this violation of federal law, with all the consequences that may entail.
Way 2:
Texas relative owned the handgun for 15 years and gave you the handgun last year. You took the handgun home to NC, where you have been a resident for the last 5 years. Prior to that, you lived in Texas, the same state as the relative you obtained the handgun from. Let's say that you were pulled over for a traffic violation and you were carrying that handgun as your CCW. Through the course of the interaction the officer relieves you of your weapon and as he's processing the traffic violation, he runs a check on the handgun and it comes back as stolen. An investigation is commenced over the next several days and the firearm is traced back from you, to the point where you received the firearm from your family member, and your family member accounts for it back to the point where he bought it five years previously at a pawn shop.
However, the date at which you took possession of the firearm was determined to be while you were still a resident of Texas. (There are ways this could be legitimately established...federal law is based on possession, not ownership. If, for example, you possessed the firearm by virtue of the fact that your relative let you have/use the firearm while you lived in Texas and the handgun had remained locked in a safe to which you were the sole possessor of the combination to BEFORE you left Texas. Any number of scenarios can result in your having legal possession of the firearm in question including, obviously, you actually being gifted the firearm before you left Texas.)
Nothing in the investigation leads the detectives conducting the investigation to believe there were any criminal ties to the original theft. In this case, you are not in violation of federal laws as discovered in the first way listed above.
One has to be very particular about these issues to make sure they're not on the wrong side of the law...and even so, law enforcement may STILL make charges because they're NOT attorneys and will let the DA decide if they need to battle this out in court.
I am originally born and raised in Indiana. I was an Indiana resident for most of the time I was in the Navy, only changing residency to SC much later in my 20 year career. I received a shotgun from Dad during the period in which I was still very much an Indiana resident, so that transaction did not have to go through an FFL. Now if Dad were still alive today, and I've been retired out of the Navy for nearly 2 decades and very much a SC resident for longer than that, then that transaction would have to go through an FFL dealer.
All of this revolves around "possession", "state residency", and what the federal laws say. If you are residents of the same state at the time of the transaction which establishes possession, then no problem. If you are NOT, then at least one FFL is required...two if there's a mix of long guns and handguns and you want to divide it up. (Long guns can go through an FFL in the state of the transaction, where you can then take possession of them. Handguns must go through an FFL in your home state in order to take possession of them.)
If a legal scenario crops up like you postulated, DO NOT talk to the police without consulting with an attorney on the matter. Even if totally legitimate within the eyes of the law, these matters can get convoluted very quickly and law enforcement isn't there to be on your side, looking for a way not to charge you with something. Get an attorney and let the attorney handle it.