doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Damascus barrels and pressures

Compressed steel tubes in conjuction w/ the new fangled smokeless powder was a just a fad and giving pattern welded tubes, water pattern or Damascus tubes a bad name was to sell the steel maker's product; therefore, it was all about economics. The Brits couldn't compete on a global scale w/ other countries tube suppliers who had a cheaper wages. Also, the cost was directly related to the quantity of natural resources a country had and also the distance and type of transport to the source, furnace and forge. Leo Figiel in "On Damascus Steel" notes that after the pattern welded(helical or spiral wound) tube was perfected by the Turks, Persians, Afghanis, Indians(India) and the Italian Cominazzi family, the tubes could be totally filled w/ powder and ignited unlike as before on previous tube types, where they could only fill it 1/4 of the length.

Kind Regards,

Raimey
rse

I have the Bodinson article too. It's short, but very informative:


"Shotshells: Black Powder vs. Smokeless - Brief Article
Guns Magazine, March, 2000 by Holt Bodinson
Despite widespread warnings to the contrary, it was not uncommon in my youth to see hunters using smokeless shells in their Damascus barreled shotguns. I've always wondered exactly what the pressure difference was between the two propellants. Well, here's some interesting Winchester test data from the 1960s.

The first set of results was based on the objective of achieving the same muzzle velocity between a smokeless and black powder shotshell. Notice the resulting difference in pressures and the greater efficiency of the smokeless powder load.

3 Dr.Eq. 1 1/8 oz. #7 1/2 3 Dr.Eq. 1 1/8 oz. #7 1/2
Winchester Trap Load Black Powder Shotshell
21.0 grs WC-450-LS 82.0 grs Dupont FFFg
1,202 fps 1,205 fps
9,600 psi 4,900 psi
The objective of the second set of data was to determine what charge of each powder was necessary to achieve a peak chamber pressure of 6,900 psi. Notice the incredible difference in powder charges.

2 1/2 Dr.Eq. 1 1/8 oz. #7 1/2 4 Dr.Eq. 1 1/8 oz. #7 1/2
Smokeless Handload Black Powder Handload
16.0 grs. WC-450-LS 109 grs. Dupont FFFg
6,900 psi 6,900 psi
Many of the old Damascus guns are beautiful indeed -- really pieces of gun art. Most can be returned to the field with great effect. Fortunately black powder shotgun shells are readily available from a variety of sources today so be sure to use them.

COPYRIGHT 2000 Publishers' Development Corporation
COPYRIGHT 2000 Gale Group


There are instances of shooters sending their new-fangled guns back to the makers to be retrofitted with damascus tubes, and there are guns which had faux damascus patterns applied, evidently to make them look like a superior product to steel.
RG

I shoot a couple of damascus guns and have never had a problem, i use 2 1/2 inch shells. I have only seen 1 burst barrel in my 30+ years of shogunning and it was a remington 870 circa 1990's

For the first 25-30 years of hunting ducks in the fishing village where I grew up, all the older gunners used nothing but what they considered the "best" of shells: premium-priced, high-brass 12 gauge CIL (Canadian Industries Limited) Imperials---"Blue Imperials" they called them because of their royal blue colour. They made no distinction of the guns they used them in, twist, damascus or fluid steel. As far as I know, they still don't.

In 1966, Ithaca was still at it warning about shooting the
"Dangerous" Booby Trap Damascus and twist-laminated shotguns.
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Stallones,

Thanks for posting that one. A fascinating document. So they assumed any time a damascus barrel burst it was some how defective. Could not have to do with extreme pressures, obstructions...


Pete

In place of specialised loads,why cant one use "gagemates,"
one or two gauge down, and shoot standard factory?
This must tone down the pressure to that 6kpsi range,no?

They might have a point about those old Ithacas.

It is interesting to note I have a twist bbl'd Lefever H on which a "Flaw" could be seen with the unaided eye. At 14"s from the breech on the left bbl tha appearence was that it had been struck on a sharp cornered object & dented in. It had then apparently been fired, resulting in a crack about ¼" long following a weld seam. One side of the crack was still dented in & the other side had lifted leaving an opening one could look through to the opposite side of the bore. This gun had been bought very cheaply as a parts gun & the bores were "Baddly Pitted". I subsequently put my expanding dent plug under the break & raised the part which was dented in & hammered down the raised flap, till one had to look very closely to see the crack. It was then placed in the "Firestone Proof Chamber" & several factory 3¼de-1 1/8oz loads fired with no visable results. Then several more 3 3/4-1¼oz factory "High Brass Express" loads fired with identical results. Finally several more handloaded shells using a lower velocity loading of 1 3/8oz shot were fired. It still sets in my rack today & one now has to use a magnifier to even find this crack. Now I realize some of those "Hidden Flaws" which cannot be seen may be miles worse than was this one with daylight shining all the way through, seems sorta doubtful though, doesn't it?? Also this flaw was not in the High pressure chamber area, "BUT" for how many years were we told that was where the dangerous area for a damascus/twist bbl bursting was, right out there where your forward hand was. I didn't then & am not going to now, because I Know for a Fact this bbl is cracked, but all those shots I fired through it "Could" have been fired from a normal shooting position & I would still have both hands & all of my fingers.

And we all know, Miller, where the cognoscenti said the highest pressures were: right above your left hand!