So... barrel steel discussion here?

[Joe S]

Jerry

Here is Eric’s question:

Has anyone with a metallurgical background conducted a study, or is aware of a study, which examines what may be happening with a barrel of such material over time and use?  Not speculation; any kind of study which has really scientifically looked at the effect of repetitive pressure and 'typical' shooting use upon the structure of the steel?

I believe he has got an answer, and the answer is no, none of us here are aware of such a study.  It probably does not exist.  Studies of this type are expensive.  Big gun barrel manufacturers who can afford to do them don’t look at 12L14, and the small folks can’t afford the study.  12L14 is not used as a pressure vessel at all, at least as far as I can tell. 

[T*O*F]

the small folks can’t afford the study

My son is a civil engineer.  When he was at Tulane, while they still had an engineering program, they did materials testing in the lab there.  His specialty is  bridges, so that testing was relevant.

Perhaps, someone could find an engineering student who's also interested in muzzleloading to take on such a project as a masters or doctorate subject.

[tpr-tru]

Eric,  have you read the report of Don Getz when he and John Bivins did "blow up" tests (for lack of better terms) on barrels.   I think it is posted on this forum.

[bob in the woods]

Somewhere, it is posted, but I can't lay my hands on it. I remember that Don took a section [ 10 or 12 in ]  of barrel and breached both ends after filling it with powder [black powder] . There was a touch hole in the centre of the barrel section which they lit via a fuse. The barrel held.  I think the words were "  I can't believe all that fire /pressure came out of that touch hole, but it did "  or something like that. 

[Gaeckle]

I don't think of this topic as an argument. I try to learn all I can from any source even at my age. The simple topics become boring to me but topics like this are interesting.  In my opinion anybody with a minimal amount of knowledge knows that mild steels are not ideal. But that is really not the object of Eric's original question. He never got an answer. But most of us learned something. Ideal is perfect. Perfect includes the perfect shooter. I'm going to keep studying this subject for a while.

Absolutely not an arguement in any way, but rather, by all means a very well balanced discussion. Lots of imput.

[davec2]

Original question from Eric:

Has anyone with a metallurgical background conducted a study, or is aware of a study, which examines what may be happening with a barrel of such material over time and use?  Not speculation; any kind of study which has really scientifically looked at the effect of repetitive pressure and 'typical' shooting use upon the structure of the steel?  I would be interested to know this.

My direct answer: Not likely.

Additional thoughts:  I am a rocket propulsion engineer.  I work with excellent material specialists and stress analysts.  The hardware we design, build, and test is some of the most demanding on the planet....very hot.....very high pressure...and, as Dr. Werner Von Braun once said, "In the space business, a reliability of 99.999% means total disaster."  Specifically in response to Eric, I am not sure how you would even design a representative experiment that would cover all of the variables (number of shots, rapidity of the cycle, clean bore, lightly rusted bore, overall aging between firing cycles.....) you get the picture.  Not an easy (or inexpensive) test to design and do, and the interpretation of results would be open to even more speculative conversation.

That being said, anything mechanical can fail under certain or unknown circumstances, even if being used as designed.  If being used beyond design limits (i.e. short started ball, shooting out your ram rod, etc.), all bets are off.  For me the question is, "how likely is the failure of a 12L14 barrel under normal circumstances ?"

Some statistics about other things I do routinely that I think are relevant: 

I have several steps around my house.  From the CDC:

12,000 stair accidents result in death every year in the US and over 1,000,000 injuries ranging from minor to critical.

I am older now.....I go to the doctor a lot..........From the Journal of Patient Safety:

Somewhere north of 250,000 deaths a year are directly attributable to medical mistakes.

I still drive...and in Los Angeles no less !.....From the National Safety Council:

38,300 people were killed and 4.4 million injured on U.S. roads in 2015.

I have done a lot of what I will call "adventurous" things in my life...many years in the US Navy  (floating around in salt water in a big iron box filled with explosives, gun powder, missiles, gun projectiles, 300,000 gallons of fuel, and 440 volt electrical systems), scuba diving, mountain climbing, small aircraft flying, handling high explosives, handling rocket propellants, etc., etc. 

If a barrel made out of 12L14 frightens you, by all means don't shoot one.

Personally, I will keep shooting all of mine because I put being killed or injured by flying 12L14 fragments from one of my barrels right up there statistically with winning the Lottery or being hit by a meteor.  I just can't worry about possibilities that remote...I would never walk down my front steps to get in the car and go to the doctor........

[boman]

.I would never walk down my front steps to get in the car and go to the doctor...

Now that's just plain funny, especially coming from a for real "rocket scientist"

[galudwig]

.I would never walk down my front steps to get in the car and go to the doctor...

Now that's just plain funny, especially coming from a for real "rocket scientist"

I guess after all it did take a rocket scientist to answer the question... 

[Eric Kettenburg]

.I would never walk down my front steps to get in the car and go to the doctor...

Now that's just plain funny, especially coming from a for real "rocket scientist"

I guess after all it did take a rocket scientist to answer the question... 

Best response yet!

[Dphariss]

Eric,  have you read the report of Don Getz when he and John Bivins did "blow up" tests (for lack of better terms) on barrels.   I think it is posted on this forum.

"Testing" 12l14 is irrelevant since it possible to test a number of barrels and not find a bad one. As I stated the iron barrels used in trade guns were often riddled with flaws and did not necessarily fail.  Better to look at the early TC Hawken "problems" where they got sued several times and had to use the "handloader" defense to escape and in one case falsely "proved" that smokeless powder was used (it was shown some time later that Goex blackpowder would give the same chemical test color but the plaintiffs lawyers did not do the test so...). What I consider to be the final word on this is this letter sent to John Baird when he was editor of the Buckskin Report and was published.

There is more here. http://s72.photobucket.com/user/DPhariss/library/Barrel%20steel?sort=3&sc=1&multi=1&addtype=local&media=image&page=1 should work.  I did not bother the scan in the discourse from Cunningham on the subject but it was the same thing you will find here so it would be redundant.
I would like people who have sent me reports to the PM on this sight back before it was revamped a few years back since ti foolishly did not download them them and they were lost in the upgrade.
As we might expect the 12l14 users of the time used the exact same arguments to "refute" the letter that are sued by 12L14 users today.  Just remember that its possible to shoot tennis balls with a PVC pipe with BP if the charges are light and the people doing it stupid enough.  Here is a question. If you were flying someplace in a light aircraft, Cessna 180 maybe,  perhaps out over the AK Range where severe turbulence is common. Would you want the control cables made of aircraft grade, approved cables or something the cable maker specifically says not to use in that application? Just curious.

Dan

[galudwig]

the small folks can’t afford the study

My son is a civil engineer.  When he was at Tulane, while they still had an engineering program, they did materials testing in the lab there.  His specialty is  bridges, so that testing was relevant.

Perhaps, someone could find an engineering student who's also interested in muzzleloading to take on such a project as a masters or doctorate subject.

In terms of a study along the lines of what Eric is asking for, it would seem most relevant to seek out shooters that can document claims of having shot 10-20,000 rounds from a 12L14 barrel and offer to buy them back so that an engineering student can look at them. I'm sure that if a mounting a new barrel (of their choice) to their rifle was also offered in addition to buying back the "used" one, there would be takers interested in furthering the cause. Heck, I bet the Marsh Family from KY could even supply sample barrels. For as much shooting as they do and after years of dominating offhand matches at Friendship, I'm sure they have gone through plenty of 12L14 barrels.

Someone else here mentioned they didn't know how to simulate that many rounds fired through a new barrel. Using "real" barrels that have been heavily used for years would seem to give the most accurate representation of the affects of pressure over time.

[Dphariss]

Jerry

Here is Eric’s question:

Has anyone with a metallurgical background conducted a study, or is aware of a study, which examines what may be happening with a barrel of such material over time and use?  Not speculation; any kind of study which has really scientifically looked at the effect of repetitive pressure and 'typical' shooting use upon the structure of the steel?

I believe he has got an answer, and the answer is no, none of us here are aware of such a study.  It probably does not exist.  Studies of this type are expensive.  Big gun barrel manufacturers who can afford to do them don’t look at 12L14, and the small folks can’t afford the study.  12L14 is not used as a pressure vessel at all, at least as far as I can tell.

If looking at blown up MLs is too distressing I guess we could look at the Remington shotgun lawsuit over maimed shooters where a steel that was not initially brittle but was prone to embrittlement in use, 1140M, was used for shotgun barrels and over time the barrels failed in high use applications (trap shooters) and Remington not only had to pay out for some gruesome damages they had to pay everyone that owned a shotgun in the serial number range (why no recall I have no idea). This steel was plenty strong enough for the use. Shotguns with modern ammunition ARE subject to barrel flexing do to the fast powders used and the pressure level (which is significantly higher than BP would produce for the same velocity).  So while the steel was strong enough and in the case of the burst shotguns stood up for thousands of rounds then eventually became brittle, work hardened and failed.  Cold rolled steels are ALL work hardened intentionally from the mill the brittleness makes them easier to machine. Free machining cold rolled steels are not only brittle but they are riddled with inclusions of lubricating metals. This cannot be "fixed" by normalizing since the inclusions may get WORSE if this is done. I will say that the last Douglas barrels I got back in the day dis show signs of being annealed. I know of one of these that was shot with a significant overload several times and the fired with a stuck ball and only bulged. There is a photo of this barrel with 1/2 the bulge machined away on the photobucket page. Typically the 12l14 barrel will not bulge it breaks since the brittleness will not allow it to flex so I suspect that this barrel was one made after the Douglas failures of the late 1960s and I an some others think they annealed the bars before the drilling process possibly at the mill. I THINK they had  them annealed because the last ones I used had a very hard oxide coating that would dull a file and was heck to remove. Don King told me he would "pickle" them to get it off.
People like to make excuses such as comparing shooting a barrel of a unsuitable alloy to the risk of falling on the stairs.  My question of course would be would you willingly use a stair that was very poorly designed and the same design/materials had been known to fail unexpectedly either immediately after construction or after years of use and people were maimed or killed as a result? If we look at the NUMBER of uses of stairs every year (day?) vs the number of serious injuries I suspect the risk is very small.  Probably a billion uses in the US every day if such a study could be done. I personally used stairs in my house at LEAST 10 or 14 times just yesterday. If we consider each STEP a "use" the numbers just in my state of about a million people go off the scale. I would also point out that in commercial buildings at least there is a code for stairs and their design and construction and materials are surely specified. Because faulty design/construction/materials have caused injuries.  So, by and large the accidents on the stairs are invariably due to mistakes by the user not the design or construction of the stair. How about drunk drivers? Chances are every time you drive any distance you will meet a vehicle driven by someone who is impaired by drink or dope. Many are pretty good at it and can get away with it for years, especially if they have an "understanding" local sheriff's dept. I suspect only a small percentage actually kill or maim other people? Does this make it OK? If we want to make comparisons lets compare my mech infantry unit in VN. We used to do a lot of "recon by fire", we had contacts with NVA and shot a lot of ammo. I have no idea how much I used personally but at the time i figured between the Mq6, the M60 and the 50 cal it would make a pickup load.  The 60 gunner across the road from me put out so much fire one day that the forend on his gun got hot so he used a flack vest as a "pot holder" and bonded the two together. In the time I was there we never had a barrel failure I know of with all that shooting and all that abuse. I did see a Browning locked up when the bolt forced the locking lug down so hard it deformed the receiver I suspected it was out of time slightly. Why no failures? Because the barrel steel was CAREFULLY designed and selected for that purpose. I have watched 50 cal Brownings shooting 100 round bursts in a quad mount. At night after the first 100 its possible to see the location of the bore in the barrel while standing to one side. They would typically shoot 2-4 such bursts of fire at a session just for interdiction or shooting over into North Vietnam just for fun. No failures. I have heard 50s cooking off and shooting on theitr own (its a closed bolt design) but the barrels never failed. Even shooting old ammo that produced cartridge case failures. But guns blowing up in the military is hard on morale so the military is careful about the materials used.
Btw has anyone here ever talked to a barrel maker who DIDN'T use 12L14 about it? Other than myself, probably not. Heh heh!
Dan

[Dphariss]

Somewhere, it is posted, but I can't lay my hands on it. I remember that Don took a section [ 10 or 12 in ]  of barrel and breached both ends after filling it with powder [black powder] . There was a touch hole in the centre of the barrel section which they lit via a fuse. The barrel held.  I think the words were "  I can't believe all that fire /pressure came out of that touch hole, but it did "  or something like that.

This was in an old DGW catalog and IIRC was in print for years. Things like this IGNORE the fact that the mill run steels and free machining steels have FLAWS and INCLUSIONS that are not present in every bar or every 12" section of any bar. Given that any part of any bar of 12L14 may not have any flaws and is used in testing and found to be sound does not mitigate the danger of the NEXT bar or piece of one.
BP in CLOSED BOMB testes (a strong closed vessel used in pressure testing) would produce 100000 psi. This is enough to burst many steels. BUT gun barrels are NOT closed bombs and a section of barrel with a vent is not either.  So its obvious that the pressure developed was less than that needed to burst that particular piece of steel.  There is a SOUND REASON that there are industry standards. Why the piping in oil refineries is ALL Nuclear grade steel (way over gun barrel quality). Why welders in the refinerys, pipeline industry, pile drivers unions and almost any place must be CERTIFIED. Why SPECIFIC alloys are specified. Why the military will instantly cancel barrel contracts if an inspector finds ONE PIECE of out of spec steel in the corner of the building.  Why the Italians like Uberti all use a gun barrel spec steel in the guns, ML or otherwise.  But in America we have the "cheaper is better" attitude in MLing. People will not pay for a barrel made of 4150 mil spec. First for small operators its hard to get since its only made in large lots like 100 tons. Its hard to cut and a cut rifled barrel will need lapping. Can't do that and still get some cheapskate ML shooter to pay 400+ for a barrel.  So short cuts are taken. Barrels made of a steel that is "not recommended for pressure vessel use" are easy to cut, cut really smooth the exteriors machine like butter too so there is no after work to do. they screw in a breech plug so the tang lines up with a flat and viola! A barrel is made. Of  course the breeching has oil/fouling traps and needed to be replaced or reworked. But if the new owner never checks who cares? Right? After all the makers really know their stuff right?

[Joe S.]

very nice counter argument, being in construction the steps part does ring the bell.So with that said are there builders here who refuse to use barrels made from steels less than ideal for muzzleloader barrels?I try to see both sides so I get the I won't be able to charge the extra amount for better steel and Extra labor costs involved.There must be a middle of the road but again are you just rolling the dice?

[WadePatton]

...
Btw has anyone here ever talked to a barrel maker who DIDN'T use 12L14 about it? Other than myself, probably not. Heh heh!
Dan

Of course I have.

Thanks for your input Dan.  Always appreciate your experience and straight talk.

[Eric Kettenburg]

So I guess in light of all this, and I appreciate that this has been maintained as a civil and largely factual based conversation (I hate seeing threads locked), would I be a troublemaker to bring up the super long fowler barrels made of 12L and threaded together in two pieces?

 

[rich pierce]

So I guess in light of all this, and I appreciate that this has been maintained as a civil and largely factual based conversation (I hate seeing threads locked), would I be a troublemaker to bring up the super long fowler barrels made of 12L and threaded together in two pieces?

 

Troublemaker or one who lives under a bridge?

[Joe S.]

LOL

[Eric Kettenburg]

Is that seriously how you see it?  Because I have to say - much of the information posted here is based upon metallurgical fact, and yet there seems to be an ample pushback, but with little factual evidence as refutation.  Plenty of anecdotal evidence.  We as consumers of these barrels and people who rely upon such barrels to make a living are relying upon the makers of blackpowder barrels to undertake the due diligence to ensure that the base material is sufficient for product safety, yet here we have the manufacture of such material very clearly stating such material is not suitable for gun barrels.  So in light of that, I'm also thinking of certain practices involved in the making of these barrels.  I know that the concept of threading two pieces together to yield a longer blank/finished product has been very controversial, certainly more controversial than the use of 12L itself.  Perhaps not in print, but I have personally been either party-to or present during very heated arguments relative to this practice.  Given the articles and factual information Mr. Kelly has put forth and given the additional information in this thread - Mr Phariss I don't agree with you all the time but your information is extremely valuable so thank you - I think it's a legitimate concern, especially given that I've used long barrels made in this manner and furthermore would like to continue using extremely long barrels for particular projects.  So what does such joint construction do to the structural integrity of the material? 

I don't see it as trolling despite the fact that I often try to interject a bit of levity into pretty much any situation.  That's to be considered standard.  From me, anyway.

[Joe S]

super long fowler barrels made of 12L and threaded together in two pieces?

No worries Eric - as they say, God watches out for drunks and fools....


That issue aside, pressure drops off rapidly as you go down the barrel.  How far are the threads from the breech?  Another issue to consider is thread engagement.  Rule of thumb for engineers, five threads will give you the same strength as the original material.  There are caveats, but this is a good estimation.

[Eric Kettenburg]

Typically right at the junction of the octagonal section to the round section, so anywhere from @ 12" to 16".  Still a good bit of pressure.

[JCKelly]

Davec2

Seems to me you rocket guys had some failures in the 1960's because some heat treated alloy steel parts, maybe shells, don't know, failed in a brittle manner. Tensile strength just fine.
About that time someone developed the science (engineering?) of fracture toughness.

Barrels rarely blow because the metal has too low a tensile strength.

The metallurgy is tedious to describe. Good reading for an insomniac is my three-part series in 1985 Muzzle Blasts. You know how to get them.

Tensile strength is not the issue here. Just for fun, here is an excerpt from Nov 1985 article, which in turn came from ASTM Technical Publication No. 158 (1953),
page 48.

"Mr. Barnaby deplores: 'Recent cases have occurred of fracture in Bessemer bars...from some trifling blow or strain...they nearly all took place during the late severe weather at Chatham.' In the ensuing discussion of this paper Mr. Barnaby was roundly denounced by the assemblage (Dear Reader, I can personally assure you that human nature has remained unchanged over the century which separates N. Barnaby from J. Kelly). However, in the same discussion, one Mr. Kirk complains of the cracking of steel in a mysterious manner. In particular, he cites a steel plate that 'when cold, on being thrown down, split right up. Pieces cut from either side of the split stood all the Admiralty tests. Now given a material capable of standing without breaking an extension of 20 percent he wanted to know...how a plate...could split with a very slight extension...not to the extent of 1 percent.'
Mr. Kirk thereupon asked the steel makers for a remedy to this problem...His question was totally ignored by the members present. Today the problem is yet with us, and modern engineers and metallurgists are still striving to satisfy Mr. Kirk's request."

A century later, fracture mechanics expert Charles H. Maak related a similar experience. When a deliveryman accidentally dropped a bar of 1200 series steel onto concrete at about 32°F, it too broke apart. This is the same kind of steel that might be expected to elongate 15% or so in a tensile test.

To quote from a favorite TV series, "The information is out there. All you have to do is let it in"

[rich pierce]

Is that seriously how you see it?

I don't see it as trolling despite the fact that I often try to interject a bit of levity into pretty much any situation.  That's to be considered standard.  From me, anyway.

I was attempting some levity, Eric.  Everybody knows you're a serious researcher and student of the longrifle.

Maybe the threaded joint question could be raised in another thread.  It seems tangential to the materials question.  Maybe more accurately, overlapping but not congruent.

[rich pierce]

Back to barrel steels:  it seems to me much of the data and most or perhaps the critical incident(s) with 12L14 were with Douglas barrels which it seems may have accumulated additional stress from being drawn to octagonal shape. Perhaps most agree at least this was an additional variable.

I am thinking of barrel makers contemporary with Douglas barrels; GRRW, Sharon, and Paris come to mind. I seem to recall Sharon button rifled their smaller calibers then stress relieved the barrels.

How much does the processing (drawing to new shape vs stock removal) and stress relieving of 12L14 affect the properties important for integrity in use as a ML gun barrel?  Are we tending to lump all 12L14 barrels together here?

[Joe S]

Eric

I'd think that this could be done safely, but I would take it seriously.  Number of threads per inch matter, finish on the threads matter, and the torque spec matters.  Otherwise, there should be enough steel there to do this in a reasonable manner.  Talk this over with an engineer.  The calculations are straightforward, and whatever the engineer charges you is money well spent.

Rich - Sorry for the digression but I'm all done with this now.  This is a straightforward mechanical engineering problem, and doesn't need a whole thread of its own.