Re: SBR transport across state lines?
....right on the money, Lazy 21, and furthermore I wouldn't trust that the clown on the phone at your local BATF office knows the law. Maybe a good idea is to get him to email you the law so you can see what it says. His interpretation of it based on his level of reading comprehension might be off.
Another way to find out what the law is is to look it up. Finding the United States Code Annotated is easy. USCA is the Federal statutory law written by Congress. It is THE law on federal matters.
Generally, the US Supreme Court and US Appeals Courts hear appeals and apply the facts of USDistrict court cases to statutory law in an effort to harmonize statutory law with facts - deciding whether Congress has written a statute that comports with the US Constitution, and in criminal cases, prosecuting those of us who a US Attorney has accused of offending a federal criminal statute, for example. Annotations are appellate court decisions, an effort to settle a disagreement about what the law means and how the trial court applied it. Decisions are stories, in a way, written by the SC and the AC's to guide us in applying that statute to those facts in future cases. We call it "case law" and "Jurisprudence" among other terms.
Try USCA, Firearms, Transportation, Interstate Transportation of, for example, and then maybe a case or two that explains what happened on the road that day.
Yet the best way to find out what the law is is to pay for it. Ask a lawyer to find out for you and pay him for doing the work. That will be cheaper than getting pulled over for speeding, having a rookie trooper just trying to do an extra good job, asking you every question he can think of, and you trying to abide by the law and trying to tell him everything you can think of which will include you have a weapon and your going across state lines to see Uncle Johnny and now he gets a silver star by his name for the charge under USCA - your trip may be delayed by weeks, or at least hours....and THEN you'll need that lawyer to find a lawyer in the state where you were arrested at which point that one will charge you out the butt because of the Federal charge and your not local......... This is sounding like a $15,000 mess if caught in terms of total economic inconvenience. The legal fee is probably 10k.
These are mere musings - Not legal advice although I am a lawyer. But it is simply a matter of "An ounce of prevention.........".
Another idea; mail the gun. Or mail the bolt. If it isn't a whole, functional firearm, is isn't a firearm under that law...used to be - but check current status of the law.
P.S. We lawyers are excellent at telling others how to take care of their business, but we're terrible at taking care of our own.