Author Topic: Proof Marking  (Read 17337 times)

Offline JTR

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Re: Proof Marking
« Reply #25 on: March 16, 2010, 04:04:40 PM »
Why should we look down upon them  because they come from India .

You answered your own question.   

Simply because they come from India. :o

John
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Daryl

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Re: Proof Marking
« Reply #26 on: March 16, 2010, 04:49:47 PM »
Again, this is the slippery slope that I am talking about.  I'm afraid that "pushing this subject" might have consequences for our past time that you can't imagine.

Good point!  I guess I was going on about them due to their being very poorly made and priced way to high for what you get.

Mike - they are sold/advertised as being shooting guns with 'live' ammo - ala guy has to do is to drill a vent. Dan is right - the barrels are seamless tubing.  The adds go into great detail about what wonderfully strong steel they are.  Perhaps this is all just a bug in my butt & I should let it go.

Offline Captchee

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Re: Proof Marking
« Reply #27 on: March 16, 2010, 05:30:39 PM »
I have never had anyone tell me they didn't want historically correct proof stamps on any of the English fowlers or Carolina guns I make. In fact I get guys sending me barrels to stamp all the time for their own projects.
 Since when is it illegal to fake Damascus? That's a new one on me. ???

 i dont mike and wont . as i said .. i dont think its right . once the customer has the rifle . they can obviosly do as they like .

 tonight when i get a chance ill find that law for you . if i recall correctly it put on the books in 1920-30 ??. some where around there .

 in the main time here is a link to one of the best sources i know on Damascus.
 at one time  they sent me the writings concerning this . ill see if i can find them  later  or get someone to point me to where they may be found on the net
 
http://damascus-barrels.com/index.html


as to the indian guns mike . yep thats exsactly whats happening . they are being drilled and made firable here


as to  seemless tubing ?????
 im kinda up in the air about this . if its the right tubing , it should be far stronger then any original  type of forged barrel i would think .
« Last Edit: March 16, 2010, 05:39:52 PM by Captchee »

Daryl

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Re: Proof Marking
« Reply #28 on: March 16, 2010, 05:55:22 PM »
They are seamelss tubing - for sure - and very thin.  The only saving grace is the low pressure generated by the large bores with normal light charges used in them.  Strength as in elasticity, hoop strength, brittleness - I don't know.

As to faux Damascus - they were made in Engand as well as Belgium.  I wasn't aware of a law against the making of them.  As late as the 1920's Damascus barrels were highly regarded form the best makers - perhaps the law had something to do with making a barrel look like Damascus and selling it as such - that could have been the gist of the law.

Offline Captchee

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Re: Proof Marking
« Reply #29 on: March 16, 2010, 11:53:49 PM »

 Good afternoon .
 I would agree Daryl. I think this may however be an issue with quality control  by the importer . Reason I say this is I have seen some of these imports with very thick barrel walls . Others with thin walls .
 But I wonder if we can honestly say if they are of tubing or not . Myself I think they probably are . However as can be seen on many smokeless barrels , the walls can be very thin  with quality steel . But in other cases  rather thick
 I think the only way one would know for sure what theses barrels are made of is to send one off to be analyzed.

 Again I cant help but  thing  if the right  tubing was being used , the steel should be far superior to  original iron barrels.  be they forged or other .
Personally I wish someone would do a factual study of what   is actually be used .
So far the only  study I have read was  the one concerning a failure that recently happened  under  re-enactment loads .
 For me  that  analysis was rather open ended  with the statement of the steel being of industry standards ??????
 Sure would have been nice to hear who’s standards that was .

 As to the  Faux/ sham Damascus.  Its been a while since I was studying the making of these barrels .
 If I recall correctly the  issue started in the later part of the 19th century
 Now again im speaking for memory of  what I read concerning this .
 But I want to  say the issue stemmed from  basically what  you and I have been speaking of here .   In so many words , cheep knock offs  .
 This created an issue that was giving the  better quality makers  a bad name .
 This was added by  cheaper steels being  etched with a Faux  pattern. Yet stamped with  markings  that suggested better quality then they were .
 Thus the un learned became  subject to being basically doped. Some of the  faux patterns were aberrantly that good  .
As I said though , when I return home ill see if I can post some reading on the subject .

 With all do respect to mike and the others here who may  not have a problem with stamping of proof marks .  What they do or do not do is entirely up to them .

 But  myself I  cant help but feel  that the stamping of even these 200 year old marking  we  could inadvertently   be  making a statement of  some level of proof or quality .
 Now that being said . I have very little doubt that the materials used today , far exceed the quality of the original barrels.

 I think though we may  be forgetting that these marks are not decorations . Even though that is our intent today . They were not  some company or organizations name.
 But more a  type of certification  .

 Also I would like to say .  Im not  wanting to seem like im arguing any point here .
 On my end , this is just a discussion . Nothing less , nothing more .   

Offline Captchee

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Re: Proof Marking
« Reply #30 on: March 17, 2010, 04:13:53 AM »

mike .
 finding the information in my library is like  finding a needle in a hay stack .  so i posted a request for the info over on the double gun forum .
 now this link is prior  to  the laws being enacted . but it shows the issues that were building .
 its a rather good read IMO  and give something to think about

 now  you will notice that at this time the US  was basically standing on a buyer be wear stance .
 Kinda like today LOL . But I remember reading  where  we also changed our laws in the 1920-30
 I just gotta find it

http://docs.google.com/Doc?id=dfg2hmx7_302dwsjk9cs

Daryl

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Re: Proof Marking
« Reply #31 on: March 17, 2010, 06:00:22 AM »

    But I wonder if we can honestly say if they are of tubing or not.  
 .  

They are advertised as being made of tubing & even give the tensile strength - the number I cannot remember - which is strange hmmmmmmm - nope- gone.  Tensile strength is only one factor of suitability in barrel steel, of course. Now, I can remember correctly if it was tensile strength or shear strength- probably tensile.
« Last Edit: March 17, 2010, 06:01:19 AM by Daryl »

cal.43

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Re: Proof Marking
« Reply #32 on: March 17, 2010, 12:56:02 PM »
back to topic,
there´s a prooflaw for gunparts in Germany since the 19 century. If the barrel has a vent or drum it have to be proofed. Without or as blank it´s only a iron tube. So no problems with parts etc.
Since Winnenden there might be problems with customs officers and your client has to explain a few things and have to know the gunlaws, because most Custom officers often have no clue . The proof can be made by the proofhouses here in Germany.

Daryl

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Re: Proof Marking
« Reply #33 on: March 17, 2010, 04:39:51 PM »
cal43 - do you know the proof's for different muzzlelaoding guns?  In 1850 England, they were pretty much a joke for large bored guns.

josephprivott

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Re: Proof Marking
« Reply #34 on: March 18, 2010, 01:01:12 AM »
I don't suppose there's a way for you to block the touchhole where an inspector would be satisfied that it wouldn't fire? (I would be pretty mad if an inspector took a dental tool to my property and started fishing around).
Maybe some kind of pin fixed with an organic mastic like cutler's cement (well cleaned-up after so it's less obvious) that the buyer could knock out with a nail punch?

Daryl

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Re: Proof Marking
« Reply #35 on: March 18, 2010, 04:27:50 AM »
If a gun is drilled and tapped for a vent, and a 'blind' vent ie: with no hole, is screwed in, the gun will not function and should therefore not be a firearm.  Simply drilling and pulling the blind vent then replacing it with a real vent - or, make a vent, properly cupped inside, but not drilled through, then all one would have to do is to drill a 1/16" hole in the middle - done.

cal.43

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Re: Proof Marking
« Reply #36 on: March 18, 2010, 10:01:09 AM »
cal43 - do you know the proof's for different muzzlelaoding guns?  In 1850 England, they were pretty much a joke for large bored guns.
Thats not the question, every gun prior a fix date here has to be proofed  and the loads are writen in the prooflaw and the clerks don´t ask for sence.

Offline Dphariss

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Re: Proof Marking
« Reply #37 on: March 19, 2010, 06:50:39 PM »

    But I wonder if we can honestly say if they are of tubing or not.  
 .  

They are advertised as being made of tubing & even give the tensile strength - the number I cannot remember - which is strange hmmmmmmm - nope- gone.  Tensile strength is only one factor of suitability in barrel steel, of course. Now, I can remember correctly if it was tensile strength or shear strength- probably tensile.

Yeah they were actually BRAGGING about the tubing at one time.
Would have to search the sites to see if this has changed, not worth it.
If its gone I assume they found out that tubing was a really stupid choice for gun barrels. But that does not mean they stopped using it.
To expound somewhat... Sorry about the "modern" content.
The strength of the steel is only valid IF the material used has the PROPER CHARACTERISTICS. Modern steels are generally designed for some specific purpose and this may well make them unsuitable for other uses to some greater to lesser extent regardless of how strong they might seem.
The problems Remington had a few years back and the problems with some modern stainless steels used for barrels prove that STRENGTH is irrelevant since most modern steels have the NUMBERS.
BUT the material must tough, not brittle, it must have good "hoop strength", resistance to internal pressure, and in the case of thin wall barrels, like shotguns especially, it must not work harden. Also note that a steel that is very tough in one application can be very brittle and weak in a gun barrel. Brittleness in a gun barrel means it can break at a pressure far below its paper strength numbers. Firearms barrels must not be shock sensitive since the loading its applied at a rapid rate. The pressure rise is steep. Rapid loading WEAKENS the material regardless of its "tensile" or "yield", brittle or shock sensitive steels are prone to failure. So its possible to burst a barrel at a pressure level well under the paper numbers. The faster the pressures rise the easier it is to break the material. This is how it is possible to "cut" steel with an HE like C-4. The pressure rise is so rapid (burn rate in excess of 20000 fps) that the steel simply breaks. While its impossible for BP to detonate under the right conditions smokeless powder can it would seem.
There are a whole range of reasons why for carbon steel barrels 4140/4150 is the best choice. But even this must be HIGH QUALITY STEEL. Making high quality steel encompasses the entire process from materials used to the final rolling. Thus gun barrel and better steels are made in specific batches just for the quality level needed. So to get the mill to make a run of high quality steel the order must constitute enough steel to constitute a batch for the given mill. Gun barrel steels must be HOT ROLLED. Cold rolled steels are intentionally made brittle in the final processes of manufacture so they machine easily, they often contain various metals to lubricate the cut. These tend to form inclusions in the steel. Being brittle by design no matter the quality they are not suitable for barrels. The quality level indicates the level of inclusions and flaws allowable in a bar. Bars of high quality steel are stamped with the quality level. The ones I have seen were stamped GB for "Gun Barrel". Also small lots of GB quality steel are very difficult to obtain and some big name "modern" custom barrel makers must pool orders to get steel or find someone with some in stock they will sell (good luck).

As an aside GB quality 1137 even in cartridge guns like 45-70 or 45-120 will withstand massive overloads of the faster grades of IMR powder with no apparent ill effects but its it not considered adequate for cartridge gun barrels by some experienced in the field. In some cases the people holding the loans will not allow it. Thus carbon steel breech loader barrels are made of one of the two 41xx alloys mentioned at least SFAIK. Many standard pressure 38 special, 38 S&W, 45 ACP barrels were made of mild steel and in the case of 45 ACP might still be in some cases. But load a +P or P++ in a soft barreled 38 special and there WILL be problems, often the thin forcing cone of the barrel and/or the cylinder is bulged or blown etc etc.

The post that started this thread indicates part of the problem. It is very difficult to blow up a modern steel barrel with BP. It is near impossible to blow a modern rifle that operates at 55000-60000+ with a 4140 barrel without a bore obstruction. Some really significant abuse has to occur OR an UNDERLOAD condition with smokeless powder. Barrel steels other than 4140/4150 are not as reliable; there have been problems with stainless guns from several makers.
Yeah, its counter intuitive but UNDERLOADS of smokeless are a prime cause of blown modern guns. Especially 357 mag revolvers. It has to do with the ignition of the charge. Poorly ignited smokeless sometimes converts to an HE. This has occurred with reduced loads of powders like 4831 in large magnum cases, it has happened in straight cases with low density loading of IMR powders 3031 is the one I have had experiences with. Unique in rifle loads is very risky and low density loads in revolvers are poison. BTW its poison for field pieces too, been tested, a friend was told by a scientist at one of the Gov't testing ranges that they blew a 250 pound breech block 1/2 a mile with a reduced load of the normal powder.
Interestingly enough Dupont and Phil Sharpe both knew of this in the 1930s and Sharpe wrote it up. But we have to relearn things all the time it seems.

In the BP world we have no ignition related problems or true detonation. BP is so forgiving that almost anything, wrought iron, mild steel etc will contain the pressure. Unless it doesn't. Then there is a problem. But the nature of MLing immediately throws suspicion on the LOADER. Handloading exempts the maker from liability, but the moderns have something the ML maker need not contend with, factory loaded ammo. Thus the ML maker can, if they wish, use almost anything they want for barrel steel with impunity. They can take a barrel as was done in the initiating post and load it to ridiculous levels and it will survive. Thus the court system assumes the shooter is at fault. Back many years ago people had taken 1861 rifle musket barrels, skelp welded and rolled high quality wrought iron (superior to some modern steels for the purpose BTW) and loaded them completely full of powder and they held. This "proved" than a ML could not be blown up. So this overload thing is really meaningless. It will only detect gross flaws it does not mean the barrel will never fail though being made of the proper material of the proper grade reduces the chance of any *barrel* failure after proof . The 1861 (etc) Springfield’s were well proofed before accepted for service.

A major ML maker years ago, 1970s/80s, had a rash of blowups (a Finnish maker of "moderns" just had a similar problem that considering the other events I have read about is surely material related) through creative chemistry the maker's lawyers "proved" that smokeless was used. The chemical test of the fouling was absolute. It proved that nitro was present. Case closed. Except a friend of mine with a chemical bent did the same test with fouling from BP right from the can and got the SAME RESULT "smokeless present". The plaintiff’s lawyers dropped the ball. The blowups also stopped. It was thought that the barrel steel was changed and/or they had gotten a bad lot of steel. I think the barrel steel changed but do not know this as fact. I am sure the people buying the things did not suddenly become enlightened and quit making loading errors.
There is a large amount of smoke and mirrors involved in ML gun barrels, less so with the moderns. Sometimes makers like Remington get their feet put to the fire. They used a steel that was strong enough but this alloy work hardened and broke. People got hurt. Remington lost in court it was unfortunate all the way around.
There are people in the ML community that have been injured to a greater or lesser extent by barrel failures. Everyone assumes it’s the loaders fault, since "you can't blow up a properly loaded barrel".

The lab results from the blown up (with an unwadded blank charge) Indian made musket in the recent past was ludicrous. In reading it I lost all faith in the lab that did it. It was an OBVIOUS "we paid you to find what we want" finding that was an obvious case of prostitution by typewriter. It read like no other blow up report I have ever seen. No analysis of the material at all. No analysis of the fracture. Just that it was caused by a bore obstruction when no bore obstruction was possible. So it was the shooters fault. But it was paid for by the maker not the owner. So the ML community got white wash not facts.
Frightening imported ML firearms are nothing new. If you read W. Greener for 1835 he was complaining about the poor quality of export barrels/guns at that time. These were going to Africa, NA and probably elsewhere at the time. From the advent of increased interest in MLs from the late 50s on all sorts of junk has come in from various places. A gunsmith here in town back about 1975 had a guy bring him an import percussion gun because it would not fire reliably. The drum in this case is kind of snail shaped but still a drum screwed into the barrel. In examining the gun he turned the drum 1/4 turn and it FELL OUT of the barrel. Yet the guy had been shooting it. Scary part is there are STILL thousands of these out there with various name brands. They sold for 90-120 bucks IIRC. People bought/buy them for their kids  :o Then there were the things that had the 2 piece barrels in which the bore sometime was a little "off" at the joint. But they were capable of being fired. Probably some of these still out there as well. If I see some such I avoid them as I would a Rattlesnake.
But not all imports are junk. The better Italian made guns are really pretty good and I consider them safe to shoot and equal or perhaps superior to some American made factory or even custom guns.

Dan
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Daryl

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Re: Proof Marking
« Reply #38 on: March 20, 2010, 03:24:14 AM »
TKS Dan - that is an eyeopener.  I was concerned about work hardening of the seamless tubing barrels myself.  Glad I sent it back.

Offline FL-Flintlock

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Re: Proof Marking
« Reply #39 on: March 20, 2010, 11:25:19 AM »
I really love when I'm not the one to blame for hijacking a thread.  LOL

When it comes to guns made in middle to far east, Forest Gump comes to mind ... They're like a box of chocolates, you never know what you're gonna get."  I lost the pic's of a "made in India" pistol a client brought me that failed to fire and it's a dang good thing too!  The drilled vent was fouled with a metal chip and I thought it best to un-breech & check things out, the breechplug took very little force with an 8" Crescent wrench to break free, matter of fact it flopped right out ... soft soldered in, poorly done at that and even if it would have been a good solder job, the joint was extremely loose fit with less than 0.150" protrusion of the plug into the barrel - yes, the barrel carried proof marks and yes it was purchased brand new via mail-order.  Pic's below are of another fine example of "made in India", they're self explanatory. 




I have followed the topic of imported guns for many years now sorting though the facts and discounting the fiction.  I have owned foreign-built guns, the best was a .50 flintlock rifle made by a small shop in Italy and the worst was a Pedersorry Kodiak, I thought the CVA Kentucky that started me in ML'ing was bad until I got the Pedersorry many years later - the CVA needed a lot of lock work but at least the barrel was good which is a lot more than I can say for that POS Pedersorry.  The most dangerous guns I've personally seen came from Afghanistan, India, Pakistan & China in that order.

Two things come into play with those guns on the "most dangerous" list and the first thing is "GREED" be it on the part of the mfg or on the part of those who purchased the cheap imported "display only" guns then drill the vent/nipple hole out and sell them for big money as "working models".  Yep, it sure does happen and more often than you may think.  One particular India mfg lists their muskets as: "Fully functional lock for authenticity ... Non-firing for display purposes only."  These "display only" guns cost between $40 & $170 depending upon the style leaving those who put their own personal greed above the safety of others with the opportunity to turn a $150 to $1000 profit by simply drilling a hole or replacing a dummy nipple with a functional one.  The second thing that comes into play is greed on behalf of those mfg's who are selling guns they know are unsafe as working models because they know they will never have to answer for the crimes.

Dan P. said a lot and I agree with most of it, not the least of which is as Dan said, rate of pressure rise but also one must consider the other all-important factors of a given material as well.  The major problem comes from the armchair, and sometimes office-based, engineers who do not understand all the parameters required to match a given material to the intended application.  Some years ago, I worked on a hydraulic unit that suffered repeated catastrophic hard line failures within a given number of cycles.  Try as I might, I could not seem to beat it through the heads of either the office-based nor the field engineers working for the mfg that the  hard alloy tubing they chose for the application could not withstand the constant stress being applied by the electric over hydraulic valves slamming open and closed.  What it boiled down to, and this is the same problem seen with the armchair engineers, is that people cannot seem to grasp the concept that a material has a long list of specifications for a reason and that reason is to allow one to choose the alloy proper for the intended application.

This is a picture of DOM tubing with a very high ultimate and yield strength that, as is clearly evident, failed rather nastily from repeatedly applied shock loads generating a maximum pressure well below the alloy's rated yeild strength.



This pic is the same DOM tubing with the difference being that it was subjected to a post-forming normalization process - take note of the much less violent failure and also note that this failure could not be generated until the shock load pressure exceeded the alloy's tensile rating.



In the above, the difference in tensile strength between the two samples was approximately 50 ksi with the second being the lower strength.  However, the higher-strength sample failed with fragmentation at a pressure level well below its rated value because it's higher strength ratings reduced its elongation factor from about 17.5% to less than 11%.  One must also note that the elongation rate will fall considerably with pressure cycles in those materials capable of work hardening.  One must also note that most any alloy subjected to mechanical forming or machining must once again be run through a complete normalization process post-work or it can be loaded with induced stresses which can result in profound changes in the alloy's as-sold properties.
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Offline FL-Flintlock

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Re: Proof Marking
« Reply #40 on: March 20, 2010, 03:15:33 PM »
Continued...

Quote
Dan P.:  The post that started this thread indicates part of the problem. It is very difficult to blow up a modern steel barrel with BP. It is near impossible to blow a modern rifle that operates at 55000-60000+ with a 4140 barrel without a bore obstruction. Some really significant abuse has to occur OR an UNDERLOAD condition with smokeless powder. Barrel steels other than 4140/4150 are not as reliable; there have been problems with stainless guns from several makers.

Point of disagreement, sort-of, with those statements.  First, one must assume that the "modern barrel" is properly made with known good materials and second, under the right (or "wrong" depending on how you look at it) conditions, BP can generate pressures in excess of 80 ksi without a bore obstruction as was demonstrated when a modern .45-70 rifle exploded firing commercially loaded blank cartridges.  I don't recall all the details but the gun was checked then loaded with a single round by a qualified armorer for some type of demonstration, subsequent investigations determined the cause to be "unknown" but specifically ruled out a bore obstruction or operator error.  The only theory put forth by agreement of the investigators is that the gun and blank were both exposed to direct sunlight for several hours prior to the explosion.

The use of high-strength alloys are not an insurance policy to rely upon either as they are more prone to fragmentation, especially those with lower elongation ratings as seen in this pic...



When it comes to proof loads, I question the use of excessive loads because while a given assembly may withstand an excessive load, how can one be assured that the "proofing" did not induce stress/strain to a point that will result in a catastrophic failure at a later time with a "normal" load?  IIRC, the Euro standard for BP guns is 160% maximum powder charge with 125% maximum projectile mass.  Personally, I don't expose my assemblies to excessive proof loads just the same I wouldn't intentionally overload a crane/derrick in the name of "testing" when that unit is expected to work in the field.  Most all critical industrial devices are subject to testing prior to being put in service and/or at prescribed intervals during service.  At no time are these devices loaded beyond a "reasonable" testing limit ... take a wire rope or sling for overhead lifting for instance, although it's supposed to have a designed-in 5:1 safety factor, the device is not tested at 5 times it's rated capacity but rather at 1.5 times the maximum capacity.  The testing will reveal certain tell-tale signs of a problem(s) without creating a hidden problem.  Lastly, I think the last thing we need is another government agency mucking up the works and sucking up our money - just look at the mess OSHA has made of things concerning powder storage & handling ... afterall, it was the powder mfg's who are to thank for all the safety developments in packaging & shipping, now those efforts are being corrupted by legislative schmucks who do not have a clue what in the h*ll they are talking about, does anyone really think that's a good idea to wish upon yourself?

Mark
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Daryl

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Re: Proof Marking
« Reply #41 on: March 20, 2010, 04:32:36 PM »
I agree with this line of posting- and believe shooters need to kow this information.  I am going to lock this topic now so we don't get carried away into a political discussion that will not be tolerated.