Ah William. Once again the blind hatred is making you appear the fool.
In the hope of learning something 2 of the barrels used by Sherman Bell, with the technical support of Tom Armbrust, and published in
The Double Gun Journal Vol. 10, Issue 4, Winter, 1999, Finding Out For Myself Part II and Vol. 16, Issue 2, Summer 2005, Finding Out For Myself Part IX were given to the pseudonymous Zircon, a metallurgical engineer, who posted Contribute Junk To Advance Barrel Strength Knowledge on two public internet forums in 2005 requesting vintage barrels for composition and strength testing. By 2006 he had accumulated almost 40 samples, both Fluid Steel and Pattern Welded. Part of the collection included the Damascus barrels from the Parker GH and the Vulcan Steel barrels from the Parker VH that had been the subjects of Bell's destructive testing.
Both guns were subjected to sequentially higher pressure loads at about 2,000 pounds/square inch (psi) increments. The GH testing started at 11,900 psi and one chamber ruptured at 29,620 psi. The VH started with a Proof Load of 18,560 psi. Both chambers bulged at 29,620 psi and ruptured at 31,620 psi.
A formal Failure Analysis was proved to the BOD of the PGCA, with photomicrographs and Energy Dispersive X-ray (EDX) Scanning Electron Micrographs, but to my knowledge it has not been published.
A partial report was placed on a Public Domain forum, and is worth reading
http://www.familyfriendsfirearms.com/forum/archive/index.php/t-55364.htmlThe mode of failure of the barrels is not necessarily applicable to our subject barrel since the failures were induced by higher and higher pressure loads, but the fluid steel barrel failed by abrupt brittle rupture, and the damascus barrel by low cycle fatigue with ultimate ductile fracture.
and what Larry said
"On the two old Parker barrels, there is a screw hole that comes up from the bottom and pins the extractors in place. Both barrels failed at that hole, because it takes a (segment) out of the side of the chamber and is the thinnest portion of the chambered area."
I communicated with Zircon in February 2008 regarding his Analysis, then again in 2015. He still had the barrel samples and intended to do composition and tensile strength testing, and also intended to submit his Failure Analysis on the Parker barrels for publication.
"Things that are plain to see" commonly are not what they appear to be, and we all "see" what we want to see.
BTW: have you purchased a wall thickness gauge yet? Looking forward to a bunch of end-of-the-chamber numbers for our knowledge base.
