Thinking about going Damascus

[Drew Hause]

There has been original research measuring the tensile strength of a variety of pattern welded tubes, several contributed by PGCA members
https://docs.google.com/document/d/1...hfDxmrNAU/edit

There were possibly 40 pattern welded tubes donated to 'Zircon' without apparent follow through.

There ARE failure analyses, including Ron Graham's report of Sherman Bells ruptured GH Damascus barrels and VH Vulcan Steel barrels, and the PCGA has a copyrighted and unpublished formal metallurgical failure analysis of those barrels.
https://docs.google.com/document/d/1...K7G9IBs4g/edit

And no "orange lace" from mythical internal corrosion in these freshly cut tubes ready for tensile testing and composition analysis



And this from Mike George, Technical Editor, “ShootingUK”
http://www.shootinguk.co.uk/answers/...us-steel-13767
“In the USA there is one chap who is active on websites who believes that all Damascus steel barrels are so dangerous they should be destroyed.”
http://www.randywakeman.com/WhyYouSh...cusBarrels.htm
“But then you are likely to get piffle like this from a nation that does not have gun barrel proof legislation.”
(Piffle: “pseudo-scientific trivial nonsense, baloney”)

The Birmingham Proof House routinely proves pattern welded barrels. I have no information on the failure rate.

[Stepmac]

Originally Posted by Dean Romig

No Mike, there has been no (scientific) research confirming Twist or Damascus is/are inherantly unsafe to shoot. Anyone who states so is simply expressing an opinion or repeating the opinion of others. In the Double Gun Journal Sherman Bell conducted his own tests in order to discover 'burst' or 'rupture' pressures . No, his teste weren't ultra scientific but he used pressure sensing instruments and measured walls and exterrior measurements after each set of shots fired at increasing chamber pressures. Sure, some barrels ruptured or became deformed but these exceeded 31,000 psi.

Those Remington proof loads measured 18,000 psi which is way more than even the most powerful modern shotgun shells. Most are 12,000 psi. Lite loads are around 10,000 psi....I think. If I'm wrong I'm sure one of you shotshell gurus can correct me.





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I enjoyed Sherman Bell's articles in DGJ and read them over and over. He had a hard time to get damascus barrels to let go. He honed a set of L.C.Smith barrels to "paper thin" and loaded them with Remington proof shells and they still wouldn't explode. The only sure way to get damascus barrels to let go was to put an obstruction in the bore. Any shotgun barrel will explode if you do that.

[Stepmac]

Originally Posted by Dean Romig

No Mike, there has been no (scientific) research confirming Twist or Damascus is/are inherantly unsafe to shoot. Anyone who states so is simply expressing an opinion or repeating the opinion of others. In the Double Gun Journal Sherman Bell conducted his own tests in order to discover 'burst' or 'rupture' pressures . No, his teste weren't ultra scientific but he used pressure sensing instruments and measured walls and exterrior measurements after each set of shots fired at increasing chamber pressures. Sure, some barrels ruptured or became deformed but these exceeded 31,000 psi



.

I have about 20 years of Double Gun Journal magazines. Can someone tell me which issues include Bell's research? I haven't counted how many issues I have, but they take up about six feet on a shelf. Thanks in advance.

[Drew Hause]

The Double Gun & Single Shot Journal “Finding Out For Myself” series by Sherman Bell with technical assistance from Tom Armbrust
Vol 10, Issue 2, Summer 1999, Part 1, p. 9
Vol 10, Issue 4, Winter 1999, p. 21 - Destructive testing of Parker GH Damascus
Vol 16, Issue 2, Summer 2005 - Destructive testing of Parker VH Vulcan Steel
Vol 17, Issue 3, Autumn 2006, p. 12 - Destructive testing 8 Damascus doubles
Vol 17, Issue 4, Winter 2006, p. 28 - Destructive testing 7 Damascus
Vol 18, Issue 1, Spring 2007 -
Destructive testing on a Damascus barrel with thinned walls; calculated by O.D. - I.D. and not measured.
Destructive testing using various obstructions, including a 20g shell.
Destructive testing using a shell loaded with 3 1/4 Drams by volume or 56 grains of Unique (similar to “Infallible”) with 1 1/4 oz. shot. The chamber burst with the first shot.
The 3 1/4 Dram Equivalent load is 24 grains of “Infallible”.
Vol 19, Issue 2, Summer 2008, p. 18 - Destructive testing 1 Damascus, 6 Twist
Vol 20, Issue 3, Autumn 2009, p. 108 - Destructive testing 1 Damascus, 5 Twist “Bottom-Of-The-Barrel Wall-Hangers”


The Remington Proof Loads used by Sherman Bell and Tom Armbrust were reported to be 18,560 psi.
Total 28 vintage doubles/54 Twist and Damascus barrels + 2 Vulcan (Fluid) Steel

[Stepmac]

Originally Posted by Drew Hause

The Double Gun & Single Shot Journal “Finding Out For Myself” series by Sherman Bell with technical assistance from Tom Armbrust
Vol 10, Issue 2, Summer 1999, Part 1, p. 9
Vol 10, Issue 4, Winter 1999, p. 21 - Destructive testing of Parker GH Damascus
Vol 16, Issue 2, Summer 2005 - Destructive testing of Parker VH Vulcan Steel
Vol 17, Issue 3, Autumn 2006, p. 12 - Destructive testing 8 Damascus doubles
Vol 17, Issue 4, Winter 2006, p. 28 - Destructive testing 7 Damascus
Vol 18, Issue 1, Spring 2007 -
Destructive testing on a Damascus barrel with thinned walls; calculated by O.D. - I.D. and not measured.
Destructive testing using various obstructions, including a 20g shell.
Destructive testing using a shell loaded with 3 1/4 Drams by volume or 56 grains of Unique (similar to “Infallible”) with 1 1/4 oz. shot. The chamber burst with the first shot.
The 3 1/4 Dram Equivalent load is 24 grains of “Infallible”.
Vol 19, Issue 2, Summer 2008, p. 18 - Destructive testing 1 Damascus, 6 Twist
Vol 20, Issue 3, Autumn 2009, p. 108 - Destructive testing 1 Damascus, 5 Twist “Bottom-Of-The-Barrel Wall-Hangers”


The Remington Proof Loads used by Sherman Bell and Tom Armbrust were reported to be 18,560 psi.
Total 28 vintage doubles/54 Twist and Damascus barrels + 2 Vulcan (Fluid) Steel

Thank you very, very much Drew!

[Stepmac]

Originally Posted by Drew Hause

The Double Gun & Single Shot Journal “Finding Out For Myself” series by Sherman Bell with technical assistance from Tom Armbrust
Vol 10, Issue 2, Summer 1999, Part 1, p. 9
Vol 10, Issue 4, Winter 1999, p. 21 - Destructive testing of Parker GH Damascus
Vol 16, Issue 2, Summer 2005 - Destructive testing of Parker VH Vulcan Steel
Vol 17, Issue 3, Autumn 2006, p. 12 - Destructive testing 8 Damascus doubles
Vol 17, Issue 4, Winter 2006, p. 28 - Destructive testing 7 Damascus
Vol 18, Issue 1, Spring 2007 -
Destructive testing on a Damascus barrel with thinned walls; calculated by O.D. - I.D. and not measured.
Destructive testing using various obstructions, including a 20g shell.
Destructive testing using a shell loaded with 3 1/4 Drams by volume or 56 grains of Unique (similar to “Infallible”) with 1 1/4 oz. shot. The chamber burst with the first shot.
The 3 1/4 Dram Equivalent load is 24 grains of “Infallible”.
Vol 19, Issue 2, Summer 2008, p. 18 - Destructive testing 1 Damascus, 6 Twist
Vol 20, Issue 3, Autumn 2009, p. 108 - Destructive testing 1 Damascus, 5 Twist “Bottom-Of-The-Barrel Wall-Hangers”


The Remington Proof Loads used by Sherman Bell and Tom Armbrust were reported to be 18,560 psi.
Total 28 vintage doubles/54 Twist and Damascus barrels + 2 Vulcan (Fluid) Steel

I looked for Vol 10 issue 2 or 4. I found Vol 10 issue 3. The ones I wanted are in the mix, but darned if I can find them. The magazines are in a closet and it's not very well lit. My wife says she'll help me put them in order...she is nice to me. She is also a good sport. When we met, nearly 50 years ago I introduced her to shotgun shooting. We have one of those spring loaded hand throwers. She held the gun (a 12 gauge Miroku O/U) perfectly and broke lots of clays.

[Dean Romig]

Thanks Drew. I knew you’d come on and set me (all of us) straight.
Always good to hear from your expertise.





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[6pt-Sika]

I have nothing against a person that doesn’t care to fire guns with Damascus or twist barrels that’s their prerogative , however on the other hand if I’m shooting them and someone doesn’t like it the best thing they can do is not stay around . I was shown an article from
The American Rifleman once that was written back in the late forties or early to mid fifties . If my memory serves P.O. Ackley wrote it . He took four Parker’s all with good bores , tight etc . Two were fluid steel and two were damascus . He started loading below factory standards trying same loads in all four working his way up to factory smokeless pressures . Then he started exceeding pressure velocity etc . He burst the two fluid steel barrels and went on with the two damascus guns until he thought he’d sprung the actions enough to make lock up not safe I think the article said . Anyway those guns I’m sure had far better bore condition barrels than a good many now .

[Drew Hause]

Thinking more about Mike's question, IMHO the Birmingham Proof House's frequent proving of pattern welded barrels does constitute an ongoing "experiment'; though without controlling for uniformity of wall thickness.

Great Britain joined the Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives standards in 1980 but the new Rules of Proof were not introduced until 1984. Lead Crushers were used until 1989.

The CIP transducer “Maximal Statistical Individual Pressure” is 850 BAR = 12,328 PSI for a “Maximal Average (Service) Pressure” of 740 BAR = 10,733 PSI, and “Mean Proof Pressure” of 960 BAR = 13,924 PSI.
900 BAR is for a “Maximal Average (Service) Pressure” of 780 BAR = 11,313 PSI and Proof pressure of 1020 BAR = 14,794 PSI.
High Performance (Magnum) MSIP is 1200 BAR = 17,405 PSI for a Service Pressure of 1050 BAR = 15,229 PSI, and Mean Proof Pressure of 1320 BAR = 19,145 PSI.

Damascus barrels reproved in 1992 at 1200 BAR (WHAT were they thinking?!? )



2006 British Rules of Proof changed the process slightly
https://www.gunproof.com/downloads/rules-proofing
Part IV, “The Proof Load”, Number 27, Part A
Calls for a load of 30% over mean service pressure at a point 17mm or 25mm (about 1”), and at a point 162mm (6.38”) from the breech face a load of 30% over mean service pressure (at that point as determined by the Proof House).
The powder used in proof loads is not specified.

AFAIK the Proof House has declined to reveal the powder used, or if this is one proof load shot or two proof load shots.

[Stepmac]

Originally Posted by CraigThompson

I have nothing against a person that doesn’t care to fire guns with Damascus or twist barrels that’s their prerogative , however on the other hand if I’m shooting them and someone doesn’t like it the best thing they can do is not stay around . I was shown an article from
The American Rifleman once that was written back in the late forties or early to mid fifties . If my memory serves P.O. Ackley wrote it . He took four Parker’s all with good bores , tight etc . Two were fluid steel and two were damascus . He started loading below factory standards trying same loads in all four working his way up to factory smokeless pressures . Then he started exceeding pressure velocity etc . He burst the two fluid steel barrels and went on with the two damascus guns until he thought he’d sprung the actions enough to make lock up not safe I think the article said . Anyway those guns I’m sure had far better bore condition barrels than a good many now .

Sherman Bell cheerfully over loaded damascus barrels trying to blow them up. He loaded a Parker GH to 30,000 psi and it kept on shooting. Now most modern loads are around 12,000 psi some more some less. RST I think is around 9,000 psi. 30,000 is WAY over what we normally run into. Bell even honed an LC Smith barrel to what he called "paper thin" and tried to get it to blow. It did not.