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What I thought of Dr. Drew�s work.

My answer might not have been as distilled as I would have liked, but in essence, I said �he did the work.�
Agree or disagree, Drew is the first person to put it all in one place in a digital format.

It is an old adage, that perfect is the enemy of good.
People forget that.

As I easily remember back to the time when it was before these issues were codified and stored for posterity, the difference in the side-by-side world after this compilation, is substantial.

I also said, that the work was imperfect, but was also more than certainly adequate, givien that before Drew�s interest, I had never seen any sort of compilation of this information. Certainly no orderly effort to collect and disseminate it.
Now, we can look up just about any type of laminate steel shotgun barrel and understand a great deal about its origins and makers.

Looking forward into our digital world, having all of that information collected in one place, and freely available, it is a blessing, whether we see it as a perfect compendium collected in a perfect way, or not.

It is what we have, and it�s leading the curious into the future by looking into the past.

With regard to the matter of barrel failure, which is primarily the reason for my posting this, the framework for analysis has been set.

The technology has always been there, it has just been up to the person with the blown barrel to decide whether or not they wanted to spend the money to find out why it blew. Failure analysis is a mature practice.
Lots of time and money has been spent in the industrial age trying to figure this stuff out, if not specifically on the realm of shot gun barrels.
Metallurgists have been looking at these questions for more than a century.

There just aren�t anymore rocks to turn over.

Stan, shotgun barrels are seamless pipe, understanding why pipes split, explode, blow out, rot through, bend, kink, whatever, has been a part of that industry since it was invented.
Manufacturers have always needed to know when their product failed.

People of been polishing, staining, and looking at fractures and broken pieces of tube, since the 1800s, because you can�t deliver natural gas to gaslit cities, unless you can be sure that the pipes arent going to blow up.

Reproducing error and chasing down origin isn�t a recent thing.
It is essential for progress.

Nice post CZ. I agree entirely.

But what the heck is Hausmann's. I've heard a half dozen mention it as if everyone knows, but somewhere, sometime, one has to learn these things for the first time. Is it a match, a gun show, an auction, or something else?

Some years back, in the late 1970s as I recall a Co-Worker was running a large tracer Lathe in front of the lathe I was working. He had a large tapered sting for mounting a model in a wind tunnel he was turning the taper on. It had an enlarged portion at the end, necked down to a smaller diameter then tapered Up toward the base. There was about a 6" bore through the sting. The enlarged end was in a steady rest with the large end chucked, carriage ahead of the steady rest to turn the taper. He had a large stream of Soluble Oil in water running on part as a coolant. Everything was running great until suddenly a stream of coolant began running out the end of the bore. This was a large piece with the wall several inches thick, but he had cut into a cavity which went all the way through to the bore. The part had to be scrapped, metal supplier replaced it at their expense including return shipment of the Bad part, but we lost all the labor we had in it.

I cannot prove it but highly suspect that over the years there have been more steel barrels burst due to internal flaws than Twist or Damascus.

Double gun get together event held last weekend in Pa.
http://hhhsc.net/?page_id=18

I must have read your comments more than a couple or few times, and I figure why not just ask. How do you reconcile the mature practice of particularly gun barrel failure analysis with time and money not specifically spent in the realm of gun barrels?

I'd think gun manufacturers and maybe ammo manufacturers have mountains of blowup data, but I haven't noticed where it is available for general review. What lab can be commissioned to do a definitive gun barrel blow up analysis, or is that even needed any more? Is the forgone conclusion perfection? I'm probably reading it wrong, but Doc Drews generously shared lab results seem to report material analysis not conclusions?

No argument CZ, I hope you don't mind that I'm just wondering about some of the thoughts.

On the matter of failure analysis, it started out as a "put up or shut up" remark actually. If a person won't do the work, don't hack on the man doing it.

Like I told the man in PA, Drew did the work.

I cut and polished enough samples in the met lab years ago to be more than happy to let someone else do that stuff now.
If a person doesn't come from manufacturing, I can see how some of it seems like magic.

Perazzi used to intentionally burst one of every fifty barrels (if I remember the number accurately) they build for shotguns, by hydraulic pressure, to see at what pressure they go, and where on the barrel the failure would be. One in fifty. I'd say they would have much blowup data.

Used to be a video you could watch of the procedure they used, with narrative. I wish I could find it again.

SRH

Thanks Kutter. Now I know.

Craig: the big money is in airplanes falling from the sky and oil pipeline blow-outs. One of the metallurgical engineers told me that any pipeline/deep water drilling weld can be traced back to the date, the welder, and the yard in Houston.

Several firms will provide a formal and forensic (law suit) firearm failure analysis, starting at about $1000 and not including fees for expert witness testimony

Entropy Engineering Corporation
http://www.entropyec.com/

H.P. White Laboratory, Inc. in Maryland and Cortland, New York
www.hpwhite.com

Dayton T. Brown
https://www.dtb.com/testing-overview

I've read a few - some extremely detailed & documented, and some mostly just an expert opinion.

This is the appellate case related to the Savage 10ML II (designed for use with Smokeless Powder) with Crucible 416R Chromium Stainless Steel barrels. Expert witnesses alleged that a catastrophic barrel failure was the result of both a design flaw and a metallurgical flaw; manganese sulfide inclusions in the 416R
https://cases.justia.com/federal/appellate-courts/ca6/12-1475/12-1475-2013-08-09.pdf?ts=1411028258