Double Gun journal
 

What Year was the Sherman Bell article in Double Gun. Thanks Thomas

There were more than one. Refer to the hard cover books that identify articles by author for the first 14 years, if all else fails.

Thomas,

This is what I wrote down a few years ago when I was reloading NfB in a double rifle. The list may not have all his “Finding Out For Myself” articles.

DGJ vol 10 issue 2: Finding out for myself


DGJ vol 15 issue 1: Finding out for myself—Express Rifle Pressure Variables (Sherman Bell); beginning of series (BP load, NfB load, duplex load)

DGJ vol 15 issue 4: Finding out for myself—Express Rifle Variables Black Powder (Sherman Bell)

DGJ vol 16 issue 3: Finding out for myself—Express Rifle Pressure Variables, NfB (Sherman Bell); 4198 and other powders

DGJ vol 19 issue 3: Finding out for myself—Bulk(y) Powder in Express Rifles (Sherman Bell); Trail Boss experiment

DGJ vol 22issue 2: Finding out for myself—Express Rifle Case Fillers (Sherman Bell)


Ken

Thanks Ken. I now get to dig out my double gun Journals and find them. Thomas

Here is a list of Sherman Bell's Finding Out for Myself articles by date:

Summer 1999 Finding Out for Myself 12 gauge Pressure Testing
Winter 1999 Finding Out for Myself Black Powder vs Smokeless Pressure Tests
Autumn 2000 Finding Out for Myself III The Forgotten Tens (Lead Shot)
Spring 2001 Finding Out for Myself IV The Forgotten Tens (Bismuth Shot)
Winter 2001 Finding Out for Myself V Long Shells In Short Chambers
Summer 2002 Finding Out for Myself VI Smokeless vs Black
Spring 2003 Addendum Finding Out for Myself Parts III & IV
Updated the list Spring 2004 Finding Out for Myself VII Express Rifle Pressure Variables
Winter 2004 Finding Out for Myself VIII Black Powder Rifle Tests
Autumn 2005 Finding Out for Myself IX Fluid Steel, Stronger Than Damascus?
Autumn 2005 Finding Out for Myself Part X Black Powder vs Nitro (Rifle) Pressure Testing
Autumn 2006 Finding Out for Myself Part XI Wall-Hanger Rendezvous- “The Proof” is In The Shooting
Winter 2006 Finding Out for Myself Part XII Wall-Hanger Rendezvous & The Slow Powder Myth
Spring 2007 Finding Out for Myself Part XIII Wall-Hanger Rendezvous-Special Tests
Summer 2008 Finding Out for Myself Part XIV Wall Hanger Rendezvous- Damascus, Remington & Parker
Autumn 2008 Finding Out for Myself Part XV Bulk(y) Powder In Express Rifles
Autumn 2009 Finding Out for Myself Part XVI The Last Rendezvous-Bottom-Of-The-Barrel Wall Hangers
Summer 2011 Finding Out for Myself Part XVII Express Rifle Case Fillers

What a great list, thanks.

Thanks Ken. That will help a lot. Thomas

Thanks Jim what a great reference list. Thomas

Ken's got 'em.
These are the Destructive Test articles

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

I don't have Ken's Autumn 2005 Finding Out for Myself IX Fluid Steel, Stronger Than Damascus? listed. Is that the Parker VH test?

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.

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”

Thanks Drew .I bet a few others will be interested in this info that has been posted on this question. Thomas

Drew,
Yes it was a Parker # 90917 # 2 frame V-Grade hammerless
Jim

I don't have Ken's Autumn 2005 Finding Out for Myself IX Fluid Steel, Stronger Than Damascus? listed. Is that the Parker VH test?

Yes Jim.

This was posted on a public forum by Ron Graham in 2007 but is no longer on the internet.
http://www.familyfriendsfirearms.com...p/t-55364.html
He later provided a detailed metallurgical failure analysis (copyrighted) to the PGCA BOD


I am doing a failure analysis of a pair of Parker barrels - one set damascus, and the other set homogenous. These barrels were in a study by Sherman Bell and Tom Armbrust, published in Double Gun Journal. They subjected each barrel to increasingly heavier loads and they both failed at about 30,000 psi. Modern ammo gets up perhaps 12,000 psi, at most. That said, most folks that shoot these old gals use shells loaded to the 7,500 psi range.

During the failure analysis I noticed that the fracture length for the Vulcan homogenous barrels was substantially longer than for the damascus barrels. A close examination of the fracture surface showed progressive, low cycle fatigue marks on the damascus barrel. The crack advanced slightly with each increasingly higher pressured load. On the Vulcan barrels, both sides failed by a brittle fracture mechanism. By this, I mean the barrels let go in one fell swoop. Even though both sets of barrels failed at 30,000 psi, the behavior of the damascus barrels was superior to the Vulcan barrels, owing to the fact that the Vulcan barrels failed in a brittle fracture mode. A ductile fracture trumps a brittle fracture every time.

One of the (myths) with damascus is that it will fail at the welds where the original rods were forge-welded together. When I looked at this particular set of damascus barrels using a metallographically prepared sample, and up to 1,000X optical magnification, I saw NO EVIDENCE of weld joint failure, slag in the weld joints, porosity in the weld joints, etc.

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.

The damascus barrel let go by a mechanism known as low cycle fatigue. Each succeeding round had higher and higher pressure. After several rounds, a crack started at the extractor screw hole. Each successive round caused the crack to open up just a bit further, until finally the overpressure could not be contained and the (barrel) failed in a ductile fashion. Ductile failures in steel look like a taffy pull at about 1500 to 3000X magnification using scanning electron microscopy. There is a cup and cone appearance with a lot of micro-voids present. This appearance is a dead-set giveaway to a ductile fracture.

The "fluid steel" barrel failed by brittle rupture. The fracture surface is more or less smooth, but has some "rivulets" in it that point back towards the initiation point, which was the screw hole, again. The fracture surface was about 3X as long as for the damascus barrels. In other words, the same 30,000 psi final internal load created a lot more fracture surface in the homogenous barrel than in the damascus barrel. This indicates that, for an equivalent-length fracture, it took less energy to open up the homogeneous barrel than for the damascus barrel. The words in the Sherman Bell article were that the fluid steel, Vulcan, barrel failed much more abruptly and (violently) than the damascus barrel.

So the verbal description of the failures during firing and the visual observations of the fracture surfaces are in accord with each other. Both barrels ripped lengthwise for some distance and then the rupture terminated in a circumferential crack. In the case of the damascus barrels the crack spiraled around with the weld pattern, but it was not on a weld, rather it was on one of the in-between areas. After the damascus pattern is formed by wrapping rods together and forging them into a strip (known as "skelp") the skelp is wrapped around a mandrel, spiral paper-tube fashion, and is forge welded together. These spiral welds remained tight and the parent metal is what failed. This may seem pretty amazing, but in many, many instances the actual steel welded structure is stronger than parent metal.


At that time Graham had received about 30 pattern welded barrels and was planning metallurgical testing. I communicated with him in 2015 and he was still planning to publish an article in the DGJ which to my knowledge was not done. I also have no knowledge as to the fate of all those donated barrels :(