doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Repair of Double Rifle Barrel Bulge

Ld
Thanks for revealing that you indeed have more than a little understanding of metallurgy. I think you'll figure this out. There was an effort here to get real data on vintage barrel steels, but it somehow evaporated when our resource for the tensile testing and other lab testing suddenly vanished. I had made a tensile fixture for 12g shotgun barrel coupons and sent it to him along with some example barrel material. Others sent samples as well..

Thanks
The Alex Henry was most often seen with the 2 7/16 inch case.
Is this one that case or the more common 2 1/2 inch case?
There were nitro loadings for the BPE, but I suppose you will be
staying with the black powder loads?
Will you be using paper patched, or cast bullets?
Velocity is from 1025 fps to 1700 for most known loads.
With the bullet diameter around .366 any good 9.3mm bullet should work.
The longer heavier bullet might be able to span the bulge and maintain accuracy
Good luck
Sure hope the bulge is on the muzzle end
Mike

Mike,

I have a couple of original .360 moulds and I hope to use one of them. I do not know the case length of the rifle yet. I am hoping to get more information from the owner. I E-mailed him over a week ago now and have not had a reply.

Chuck,

I spent 32 years analyzing steel at a major steel
company's research center. A gentleman from British Steel gave me a nail that came from a Roman fort in England. Analysis of it showed that about 50% of it was inclusion material. Scary!
In the 1970s inclusions were found in the majority of metallographic cross section fields. Now, the 4140 steel that you referenced would typically show very very few inclusions. We have come along way with steel cleanliness, but I have no experience with inclusion content in the 1800s. It would be a very interesting study.

LD,
I recall being invloved in a few "inclusion investigations" over the years in aerospace. One that sticks out is tungsten inclusions in titanium lockbolts. It was coming from TIG welds done by low skill Russian shipyard welders that built Russian titanium subs and were later salvaged and the scrap sent to the U.S.. Each time the welder stopped the welder and incorrectly "dipped" the tungsten tip in the puddle as it solidified, they had to break off a small piece of tungsten. The vac-arc-remelt process and ingot trimming wasn't getting rid of it.

I think steels of the turn of the century and earlier will be very dirty on average. But there may be some really clean stuff in these specialized applications like guns.

Chuck,

You may well be right concerning expensive rifle barrels. One of the theories about the Titanic disaster is that cheap rivets were substituted for more expensive ones in the hull. These rivets failed when struck by the iceberg. Metallographic cross section of some rivets saved with a piece of the hull showed an abnormal amount of inclusions.

I thought one of the reasons for the various damascus and laminated patterns was to minimize the effects of the flaws in each individual strand of metal.

Thanks Chuck H for taking the time and showing the ductility figures.