Parker Blow Up

[Drew Hause]

So as to not create further confusion in another thread - this chamber rupture was discuss here in "Off Topics" 10-2017 (accessible only to PGCA members) and mostly here
http://www.doublegunshop.com/forums/...=491058&page=1

There was a great deal of discussion, some inane and some enlightened, by the usual suspects, and by a witness to the event. I contacted the owner of the gun last fall, and did so again today expressing my interest in evaluating the remains.

This was the postulated, but certainly not confirmed, initiator - the top rib extension screw drilled too deeply, possibly into the medial exterior chamber wall





None of us can make a definitive diagnosis without these questions answered, and a hands on examination

The critical information needed:
1. Exact chamber length
2. Exact chamber dimensions (for evidence of previous honing). The entrance to the chambers of c. 1900 12g U.S. doubles is usually .809” -.812”, tapering to .795” - .798”.
3. Exact bore dimensions (for evidence of previous honing)
4. Minimal wall thickness at the end of the chamber
5. Minimal wall thickness at the forcing cone
6. Minimal wall thickness around the burst edges
7. Does the burst barrel appear to have a “ring bulge”?
8. Can you confirm that the load was factory? Which Remington Nitro load? If not, what was the reload recipe and the expertise of the reloader?
9. Is there visual evidence of over-pressure on the remains of the shell? Extractor imprint on the brass? Cratered primer?
10. Did the shooter notice anything abnormal the previous shot through the burst barrel? Sound? Recoil?

[Southpaw]

Thanks Drew. Read the Double Guns article and examination. Toward end read about a proofing study done with Parker GH damascus and vulcan steel barrels. First I have read about proofing of Parker barrels to destruction. One of the GH barrels failed at 29,000 psi and the vulcan barrels at 29k and 31k psi. That is amazing and a pretty good margin of error.

Obviously reasonable care and inspection should occur when looking at barrels and checking for obstructions as a more forced habit. Still odds are more in our favor than I thought with some of these older gun barrels if that test is an axiom that holds true. Believe the old brittle American Walnut Stocks would split or fail before the barrel might fail.

[Drew Hause]

Here's the longer version Todd
A Parker GH with Damascus barrels and the Parker VH with Vulcan Steel barrels were the subjects of destructive studies in the Double Gun Journal Vol. 10, Issue 4, Winter, 1999, “Finding Out For Myself” Part II

A GH with Damascus Barrels was tested till destruction. The gun was described as a ‘Wall-Hanger’ having pitting throughout both barrels but none dangerously deep with several small dents near the muzzle.
The loads were started at 1,254 FPS and 11,900 PSI (400 PSI above the modern SAMMI maximum pressure for a 12 Ga.). The loads were increased in approximately 2,000-5,000 PSI increments. At the 25,000-27,600PSI range (approximately 6,000 above PSI the SAMMI Proof Pressure of 19,500 PSI), the brass shell heads started to show signs of overstress: head flattening, extrusion into the extractor slot and cracking. The chambers and barrels showed no signs of expansion or of over-pressure at these pressures. The left barrels’ chamber opened up at 29,400 PSI and the right barrels chamber opened at 31,620 PSI.
There were no signs of flaws in the newly exposed Damascus edges such as rust in the welds or inclusions even though the barrels were pitted. The failures started at the breech between the barrels, where the walls were thinned before assembly to narrow the breech width, and in which a horizontal hole is bored for the extractor guide pin, making this area considerably weaker than other areas of the breech.

and Vol. 16, Issue 2, Summer 2005, “Finding Out For Myself” Part IX

A ‘Vulcan Steel’ barreled Parker was tested to failure. The gun was similar to the Damascus barreled gun tested to failure in “Vol. 10, Issue 4, Winter, 1999, Part II”, above. Both were built on a No 2 frame so they likely had similar wall thicknesses (it wasn’t mentioned), they had close serial numbers and pitted barrels. (Both also had flaws that took them out of the collector category, so the loss of a irreplaceable gun would be lessened.)
Testing commenced with Proof pressures, which showed 1,485 Ft/Sec and 18,560 PSI in the test barrel. The pressures were raised in approximately 3,000 PSI increments. The first signs of stress occurred at 27,620 PSI and 1,734 Ft/Sec when the top rib extension raised up and the barrels started to come of the breech face. The next load, 29,620 PSI and 1,748 Ft/Sec, showed the first damage to the Barrels, stretching the chambers by .009” (that is it was enough pressure to exceed the elastic limit of the metal, repeated firing at this pressure would eventually lead to Fatigue Failure). This is the load that blew the left chamber of the Damascus barreled gun.
The next load at 31,620 PSI and 1,801 Ft/Sec blew both chambers of the Vulcan Steel barrels. It is the same load that blew the right chamber of the Damascus barrels.

The Metallurgic Failure Analysis of the two barrels was posted on a public internet forum by 'Zircon', and reproduced here
http://www.shotgunworld.com/bbs/view...34280&start=20

[Harry Collins]

Thanks Drew, The VH belongs to me and I've resurrected it with Damascus barrels that had belonged to my fathers first cousins,

[Drew Hause]

Vol. 19, Issue 2, Summer 2008, “Finding Out For Myself” Part XIV

Bell tested 2 10g Parkers; with 2 5/8” and 2 7/8” chambers, using 3 1/2” Proof loads at 19,840 PSI. Neither of barrels showed any dimensional changes even with the long shell in short chambers.

[birddogdoc]

Originally Posted by Drew Hause

Vol. 19, Issue 2, Summer 2008, “Finding Out For Myself” Part XIV

Bell tested 2 10g Parkers; with 2 5/8” and 2 7/8” chambers, using 3 1/2” Proof loads at 19,840 PSI. Neither of barrels showed any dimensional changes even with the long shell in short chambers.

That's crazy

[Drew Hause]

On the topic of crazy, in the Birmingham Proof House Trial reported in 1891, the five barrels tied in the 2nd Phase failed at 12.5 times the Definitive Proof load or 11.34 Drams with 2.82 oz. shot. That is in the range of 140,000 psi

The Trial is reviewed about 1/3 down here
https://docs.google.com/document/d/1...EK8OtPYVA/edit

[charlie cleveland]

these old composite barrel shotguns in good shape are as tuff as the fluid steel barrel guns...most 2 7/8 inch chambered 10 ga guns will not chamber the 3 1/2 inch 10 ga shell..but some will close shut with the 3 1/2 inch shell...out of 7 old 10 ga guns that i have only one will close shut with the long shell...this gun has a twist barrel in good shape i would not be afraid to say it would shoot these 3 1/2 inch shells with no problems ...the chambers may have been lengthed on this gun for it does measure 3 1/2 inch chambers...it s barrels are 30 inch but the barrel weight on the barrel is 7 lb 14 ounce the end of the barrels are twice as thick as any of my other guns...my dad hunted ducks for several years with a lefever with damascus barrels with no problems a lot of those heavy loads were shot in it...i m not saying to go use heavy loads in a composite barrel gun i m just saying if the barrels are in good shape there safe to use with loads designed for them..some of those old loads were pretty stiff in their day...thanks drew for all that you do....charlie

[Drew Hause]

On the theme of 10g and crazy

A post on the LCSCA Forum in Dec. 2014 regarding a 1906 No. 0 10g:
I was at a farm where a guy I have known for a couple years came out with this L.C. smith. He first shot the gun with Federal Premium Vital-Shok 3 1/2 Inch Magnum copper-plated 1100 fps 27 pellets No. 1 buck (27 pellets of #1 buck is about 2 1/2 oz.). I still have the box and 1 live shell. He fired one shell out of each barrel with no problems. I asked if I could shoot the gun...and fired 1 shell out of each barrel.
I have never seen a gun this old nevertheless shoot one. I thought it would be cool to hunt with it. I'm guessing from your comment not such a good idea.

and this
1917 Damascus 10g Ideal “Waterfowl Special” (NO SUCH THING) with 3 1/2” chamber (ALSO NO SUCH THING) 9-2015 thread on DoubleGunBBS
http://www.doublegunshop.com/forums/...=420838&page=1



The gun was offered for sale again in 2016 - “My brothers shotgun, he has had it approx 2 years. And fired it 50 plus times with factory smokeless 3.5” Magnums, shot a turkey with it this spring!”