The x-raying is just to determine whether or not a receiver is a reweld, since sellers have tried to pass off rewelds as uncut originals. X-raying is definitely called-for if you are looking for, and paying mucho $$$ for, an uncut original.

Many 07/02s rewelded scrapped receivers, but you are correct, Norrell and Stemple probably did the majority of them. John Norrell's in particular were so good that during an ATF audit one year back then, the field inspector confiscated a bunch of them, claiming that they were uncut originals that John had illegally registered as rewelds. Tech Branch ran them through an x-ray machine and returned them to Norrell.

BTW, back then, receivers were usually just cut once, and you could buy the halves by the 55-gal barrel. That's what Norrell and Stemple did, then they sifted through looking for a long front half and a long rear. When they did, they trimmed them to match and welded them up. But none of the M16 rewelds are from a single machine gun –– all have a front from one and a rear from another, because of this method. You also can find rewelds with an H&R magwell and a Colt rear section.

I wouldn't pay $12.5k for a reweld, when you can get an uncut RR conversion for that much. Rewelds are not as common, but they generally run $1-1.5k less than an RR conversion.

HTH.

With all due respect ... I've personally inspected a coupla dozen rewelds, and their paperwork, and from that sampling, I'd say at least 70% of the rewelds today are accompanied by Form 4's or Form 3's that list the manufacturer rollmarked on the magwell as the maker of record. While I'm sure Norrell and Stemple transferred the rewelds they F2'd with their names, very, very few were last transferred listing the name of the person who welded the pieces together and filed the F1/F2.

This is partially because prior to 1986, ATF did not require that the markings be in plain sight or of any specified depth ... so markings were hidden, or engraved with a vibrapen to create markings that would wash away with a refinish. That was legal back then. More important, in the early days many buyers and owners viewed rewelds as "reactivated" Colts or H&R's, even when they knew someone else had welded them together from scap. Hey, even today, there are folks who think they can Form 1 an SBR and not engrave their own markings ... can you imagine what went on in the days before Al Gore invented the internet? So Joe Blow bought a reweld from Norrell or Stemple in the late '70s/early '80s, and when they went to sell it years later, they just filled out the F4 as "Colt" or "H&R." No biggie at the time.

Absent markings, the only way you will know is by filing an FOIA ... but from my experience, every time I see a U.S. Property-marked M16, I assume it is a reweld until I see an FOIA or other documentation proving otherwise, because the vast majority of U.S. Property-marked M16s are indeed rewelds.

Norrell and Stemple were very careful to match the filler rod to the receiver material. The alloy milspec for the receiver forging was well-known, even back then.

I was fortunate enough to have a long phone conversation with John Norrell, years ago, discussing how he did his rewelds. I learned a lot. BTW, he brought up the subject of strength, and while IIRC he had never seen one of his rewelds come back broken, he said they are not and never can be completely as strong as an original, uncut, unwelded receiver, because while you can match the material, you can never make the weld exactly match the strength of the surrounding, uncut receiver sections: The weld will always either be weaker –– and thus vulnerable to re-breaking –– or stronger than the surrounding metal, and thus transfer any stresses to the unbroken sections. Instead of a continuous, universally strong metal, you have weak/strong/weak.

Now, the receiver of Stoner's AR design is an operationally unstressed component: When the gun is fired, all stresses are on the barrel/bolt locking lugs at the moment of ignition, or on the receiver extension (buffer tube) during cycling. The forces upon the fire-control group are significantly less, and certainly not capable of breaking a receiver wall, etc.

Handling and maintenance, OTOH, do stress the lower. Broken front takedown pin holes are not uncommon, mostly from the gun being banged or dropped while the upper is pivoted forward; the lower receiver's rear hoop, where the receiver extension screws in, is a weak point that breaks when the rifle is flexed lengthwise (any time pressure is placed on the center of the rifle while the muzzle and buttstock cannot move). In these situations, a demilled-and-then-rewelded receiver certainly is less strong.

Fortunately, today transferable M16s are generally treated more carefully, because they cost so much!

Here's a flex break –– trust me, you do not want to see this on your $10k gun: