^^ No clue. I had other business with the local branch and just had a casual conversation. The 479.102 regards making marks that are not engraved with the size and depth requirements generally met. It has nothing to do with where you place adequately sized markings of adequate depth. Adequate markings can be done with a vibroengraver, and the easy way to make your hand-engraved markings not stand out like a sore thumb is to place them under the handguard of an AR.
The truth is that if it's permanently identifiable as to the maker, you've done your job, so I wouldn't obsess over it.
Note that the (understaffed and very busy) BATFE has lots of other things to worry about other than the engraving on your personal NFA project. Really. And nobody knows what the penalty "might" be, even in the most extreme case of them getting a case of the ass for you. Further noting that getting this on their plate would be only the result of buffoonery on your part well beyond the norm. I defy anyone to present an actual case of criminal prosecution for the style, placement, or type of markings placed on a legally made SBR. Anyone? Deafening silence is the answer.
So:
The bottom line is that *nobody* really is in the business of actually nit-picking these rules (which is what they are, not codified in any law), and if you can show a good faith effort to have complied you're not likely to be hassled even in the extremely unlikely case that anyone in authority even bothered to look. Thinking that the US`Attorney General would literally make a federal case out of the fact that your markings are under the handguard versus on the barrel ahead of the handguard is really pretty magical thinking. And to begin that, someone would need to refer a case to them for prosecution to begin with. Who in the world would do that? And why? Trust me, if they get to that, they already have 100 other things they are indicting you for. And if any law enforcement agency referred a case to the AG for simply marking your SBR under the handguard as opposed to being on the barrel ahead of the handguard (breaking what law?), the AG would laugh them out of the office, as there's no way to win a case like that in court. Trust old Willie: You're not that important to them. No federal prosecutor is going to seek an indictment (good luck with the grand jury even bothering to hand up an indictment for that), and then go to a jury trial over your SBR's markings being under the handguard, and nobody else has the jurisdiction to even worry about it. Your local state AG doesn't have the jurisdiction... so "Good Luck" to a local-yokel cop trying to make a case. As we used to say in NJ when I lived there: "Fuhgedaboutit"... and sleep well.
Now: If you were an 07 FFL with a Class 3 SOT manufacturing hundreds of machineguns for resale to police and military forces, and you were being given site inspections by the BATFE for compliance, and you were wanting to somehow hide your makers markings under the handguard (and why would you at that point?), you would be wise to seek a BATFE opinion. As an individual making a SBR on a Form 1? <yawn>... nobody truly cares where you engrave it, and there's no real mechanism to "punish" you.
Make a good faith effort and relax.
The above paragraphs are written with the concept of engraving on the barrel under the handguard, which I do for the simple reason that my hand engraved markings done with my Sears & Roebuck vibro-engraver look like crap and I want to hide them. For engraving the barrel ahead of the handguard it's much clearer: Moving to that, there is absolutely no reason not to mark the barrel (or upper) and not the receiver. There are literally *millions* of rifles and pistols with the manufacturers marks on the slide or the barrel, not the frame, and it's well accepted that this is just fine. Go to uour gunsafe, grab any semi-auto pistol you have, and where are the markings? On the slide? "Colt Patent Firearms, Hartford CT" on the slide is on what I just looked at. Grab your bolt action rifle. Bet there are makers markings and their address on the barrel, not the receiver. Your AR isn't any different. YOU are only making the AR a NFA item when the barrel assembly is installed. Mark that component and, well.... fuhgedaboutit.. Don't deface a lower that will live on as a non-NFA lower for decades after you're done playing with it.
It always seems that when we discuss NFA stuff someone comes up with "But there's a $10,000 fine and 10 years in jail for <insert the offense here>. To which, in the case of "where should I mark my SBR" I say "Uhh.... <yawn again>... No".
Willie
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