Author Topic: Barrel rupture  (Read 8893 times)

Offline D. Taylor Sapergia

  • Member 3
  • Hero Member
  • *
  • Posts: 12552
Re: Barrel rupture
« Reply #25 on: November 09, 2019, 08:18:49 PM »
Bob:  in defense of Hall Sharon, the barrel's manufacturer, this rupture was caused by a second patched ball sitting a few inches above the first charge of pwder and patched ball.  The charge was likely in the neighbourhood of 80 gr. FFg and the second patched ball simply slipped back up the bore a few inches.   As you can see, the barrel failed right at the chamber area.  The plug itself remained in the standing breech tang.  Shane was standing at the far right hand end of the line of shooters and it sounded like a stick of dynamite going off.  We were having a team stake shoot, so loading fast and hard was the method.  We don't do that shoot anymore.
D. Taylor Sapergia
www.sapergia.blogspot.com

Art is not an object.  It is the excitement inspired by the object.

Offline MuskratMike

  • Hero Member
  • *****
  • Posts: 2197
Re: Barrel rupture
« Reply #26 on: November 09, 2019, 09:30:09 PM »
No Marc, you are exactly right. That is why I have rifles from .40 to .54. Moderate powder proper ball and patch size and the ability to hit "exactly" where you aim is the true key to success.
The "Muskrat" has spoken.
"Muskrat" Mike McGuire
Keep your eyes on the skyline, your flint sharp and powder dry.

Offline Mike from OK

  • Hero Member
  • *****
  • Posts: 1083
Re: Barrel rupture
« Reply #27 on: November 09, 2019, 10:00:38 PM »
"The powder makers/sellers may like the idea of big loads but common sense must be
a factor as well."

Common sense seems mighty uncommon these days.  Even here on ALR we get questions like, "Can I shoot 120 grains of 3f in a .45?"  I just shake my head. 

My opinion is that with traditional muzzleloaders we have no business shooting at long ranges with open sights and rainbow trajectories.  If hunting is involved, why would someone shoot something that lives and breathes at relatively long ranges?  My ethics must be different than these folks.  Large charges for "flatter trajectory" have no place in my book. 

The other reason I hear is more powder for more power in a given bore.  My answer to that is, if you need a harder hitting load, you need a bigger bore.  Many animals have been taken cleanly with moderate volumes of powder. 

Getting close enough to place a ball in the right spot is of course key. 

With moderate loads and pressures, I believe most modern barrels will easily outlast us if loaded correctly.

My apologies if my rant here has offended. 

God Bless,   Marc

Sound logic Marc.

I love my life and limbs. And I love my guns. I have no desire to damage/destroy any of those.

Mike


Offline Mike Brooks

  • Hero Member
  • *****
  • Posts: 13263
    • Mike Brooks Gunmaker
Re: Barrel rupture
« Reply #28 on: November 09, 2019, 10:43:18 PM »
Gadzooks! Was that a modern steel Barrel? I can't believe how it split in straight lines like that.

That barrel's maker should be published.Too many barrels are around now that were
made from extra easy to machine steels that were never intended for the stresses of
what goes on when a sudden,abrupt internal pressure occurs. I know barrel makers
get defensive about this but IF they have confidence in their products they wouldn't
have to be.
One other thing to look at is the idea of extreme powder charges.The guns I have seen
with original powder measures or flasks do not indicate extreme charges of any kind.
The powder makers/sellers may like the idea of big loads but common sense must be
a factor as well.
Bob Roller
Mine was a 1" X.50 Douglas. Flint ignition.
NEW WEBSITE! www.mikebrooksflintlocks.com
Say, any of you boys smithies? Or, if not smithies per se, were you otherwise trained in the metallurgic arts before straitened circumstances forced you into a life of aimless wanderin'?

Offline hanshi

  • Hero Member
  • *****
  • Posts: 5314
  • My passion is longrifles!
    • martialartsusa.com
Re: Barrel rupture
« Reply #29 on: November 10, 2019, 12:49:14 AM »
Could be...just could be that since the hunter AND horse never showed up, two possibilities occur to me.  1.  He ran afoul of a band of Indians.  or  2.  His gun did blow up but he was aiming at a bear at the time.  Either way, he got "et".
!Jozai Senjo! "always present on the battlefield"
Young guys should hang out with old guys; old guys know stuff.

Anonymous

  • Guest
Re: Barrel rupture
« Reply #30 on: November 10, 2019, 02:23:29 AM »
Arrived at a public range a few years back with everyone running like they were filming a Benny Hill fire drill.  There was dust and smoke in the air. Someone had moments before blown a gun up.

Pretty impressive and frightening to see a blown barrel up close and and still smoldering. Major difference between what I saw then and Taylor’s photographs was the barrel was blown up from the muzzle end. Apparently guy pulling the trigger was using one of those laser bore sighters (the kind you stick in the muzzle and the laser projects on the target so you can line up your sights on it) and decided to touch one off to see how close it shot without removing the laser device from the bore.  The shooter claimed he had no idea what happened until someone pointed out the remains of the bore sighter in the debris field....

All it takes is a single moment of distraction to set the chain of events into motion. 

Offline JohnnyFM

  • Sr. Member
  • ****
  • Posts: 352
Re: Barrel rupture
« Reply #31 on: November 10, 2019, 04:40:56 AM »
My memory of the Osborne journal entry was pretty much a conjecture that "perhaps his percussion tube burst".  I think they were in the Yellowstone country.

You got me to thinking so I went and looked it up... Yellowstone country is correct.

"July 31st:

...The next day we concluded to stop at this place for the lost man and four men went in search of him, and returned at night without any tidings of him whatever. It was then agreed that his gun had bursted and killed him or his horse had fallen over some tremendous precipice."

Mike

Hmmm... sounds like Blackfoot...

Offline Daryl

  • Hero Member
  • *****
  • Posts: 15079
Re: Barrel rupture
« Reply #32 on: November 10, 2019, 08:42:34 PM »
No! They was Crow, da--it.
Daryl

"a gun without hammers is like a spaniel without ears" King George V

Offline Mike from OK

  • Hero Member
  • *****
  • Posts: 1083
Re: Barrel rupture
« Reply #33 on: November 10, 2019, 10:03:21 PM »

Offline Bob Roller

  • Hero Member
  • *****
  • Posts: 9350
Re: Barrel rupture
« Reply #34 on: November 11, 2019, 05:07:35 PM »
Bob:  in defense of Hall Sharon, the barrel's manufacturer, this rupture was caused by a second patched ball sitting a few inches above the first charge of pwder and patched ball.  The charge was likely in the neighbourhood of 80 gr. FFg and the second patched ball simply slipped back up the bore a few inches.   As you can see, the barrel failed right at the chamber area.  The plug itself remained in the standing breech tang.  Shane was standing at the far right hand end of the line of shooters and it sounded like a stick of dynamite going off.  We were having a team stake shoot, so loading fast and hard was the method.  We don't do that shoot anymore.

I don't think the barrels of Jim McLemore made from Gun Barrel certified 4150 would
have let go. I talked with Jim last week and it appears he may be getting ready to start up
again with new barrels made from 4150.I think this is the same material as a 50BMG is made
from.He was stalled for several years because of his wife's illness and three years after her
passing away,he told me he was getting the shop ready again.I hope he does.

Bob Roller

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: Barrel rupture
« Reply #35 on: November 14, 2019, 12:00:44 AM »
We all take great pains to avoid this. And with modern materials it is a rare occurrence... usually requiring an engineered/contrived scenario or a serious case of ignorance/wrecklessness.

But how common was it in earlier times when barrels were fashioned by hand?

In Osborne Russell's 'Journal of a Trapper' a member of their party goes missing. He was never found, presumed dead, and Russell noted that one of the possible misfortunes that befell him was that his gun barrel ruptured and killed him.

I found it interesting that Russell mentioned barrel rupture as a possible misfortune. Was it common enough that it would be one of the main suspected causes for a person to lose their life in spite of all the other dangers a trapper in the Rockies would face?

Mike

The "quality" of the wrought iron barrels at that period in time depended on where the wrought iron barrel skelp came from.  Centering mainly on what type of iron ore was used to produce the pig iron then converted into wrought iron flat stock.
There was an incident at Harper's Ferry where a manager thought he could save some money.  Harper's Ferry had been buying hammer forged barrels out of Lancaster County PA.  Then switched to a cheaper source out of Bedford County PA.  The results of the switch ended up being a scandal. The Bedford County barrels had a high failure rate in proof testing.  Cost the man his job.

In a book on iron furnaces I ran into one that explained why barrels made near Reading, PA showed up on Hawken rifles made in St. Louis when there was an iron mine and furnace only 65 miles from St. Louis.  All had to do with the type of iron ore being smelted.  Her in Berks County, Lebanon County and Lancaster County PA most of the iron furnaces operated at first on bog iron ore and then magnatite iron ore.  High in iron content.  With Bedford they had to make due with hematite iron ore.  Not as rich in iron.  The same was true in the mine and furnace near St. Louis.  Hematite iron ore.  Hematite ore runs around 32 to 35% iron.  Magnatite is up around 60 to 70% iron.  Wrought iron made from the magnatite ore had a lot less inclusions of minerals not kicked out in the furnace smelting.  And not worked out in one of the numerous little forges scattered through the woods around the smelting furnaces.

Bill K.   

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: Barrel rupture
« Reply #36 on: November 14, 2019, 12:20:53 AM »
Whilst on a roll here.

Part of what constituted the "quality" of a barrel at that time was how it was forged.  Big difference in one that had been formed by hand hammering versus one made on a trip hammer.  That had to do with how uniform was the force of each hammer blow on the tube being formed.  There is an area outside of Reading, PA now known as Mohnton.  In the early 1800s there were 7 barrel forging shops along a stream in Mohnton.  All using water wheel driven trip hammers. Three or 4 workers to a shop.  Big forge where several barrels were being heated at the same time.  Just switching back and forth between skelps to insure the proper heating of the skelp. Constant hammering. Working from dawn until dusk. They could produce a dozen or more barrels a ay.  Which were then passed on to boring mills scattered around the area.

John Baird's book on Hawken rifles shows one made in the 1830s with a barrel stamped H REEDs Reading.  The stamp would actually be H Deeds.  Henry Deeds ran a barrel boring mill on ground close to what is now the Daniel Boone State Park near Reading.  This Henry Deeds was married into the Pannabecker  family who owned and operated a barrel forging mill in Mohnton.  The wrought iron skelp used to make that barrel most likely came out of Joanna Furnace near Mohnton.   After drilling the barrel was sold as 1 of a job lot of a dozen barrels to Hawken in St. Louis.  Carried by wagon into Reading, PA.  Place on a canal barge that went from Reading over to the Susquehanna River.  Then over to the Ohio River by way of another canal and then down the Ohio River and then on to St. Louis. 

Bill K. 

Offline Dennis Glazener

  • Administrator
  • Hero Member
  • *
  • Posts: 19359
    • GillespieRifles
Re: Barrel rupture
« Reply #37 on: November 14, 2019, 02:00:04 AM »
Bill,
Thanks for some  history of iron and barrel making. This has always been of interest to me. Would love for someone to give similiar history of iron/barrel making in the southern states.
Dennis
"I never considered a difference of opinion in politics, in religion, in philosophy, as cause for withdrawing from a friend" - Thomas Jefferson

Offline coupe

  • Starting Member
  • *
  • Posts: 32
Re: Barrel rupture
« Reply #38 on: November 14, 2019, 02:14:50 AM »
I have seen one bbl. rupture years ago, a dumb*** I knew lodged a ball half way down a flintlock due to refusing to clean between shots cause he knew so much more than everyone else. Any way not willing to pull the ball, he fired the rock lock and opened the barrel, didn't get hurt but scared the bejeepers out of the rest of us. Another reason why I have since swabbed after each shot...and enjoy the better accuracy from my rifle. 

Offline Mike from OK

  • Hero Member
  • *****
  • Posts: 1083
Re: Barrel rupture
« Reply #39 on: November 14, 2019, 03:28:35 AM »
Whilst on a roll here.

Part of what constituted the "quality" of a barrel at that time was how it was forged.  Big difference in one that had been formed by hand hammering versus one made on a trip hammer.  That had to do with how uniform was the force of each hammer blow on the tube being formed.  There is an area outside of Reading, PA now known as Mohnton.  In the early 1800s there were 7 barrel forging shops along a stream in Mohnton.  All using water wheel driven trip hammers. Three or 4 workers to a shop.  Big forge where several barrels were being heated at the same time.  Just switching back and forth between skelps to insure the proper heating of the skelp. Constant hammering. Working from dawn until dusk. They could produce a dozen or more barrels a ay.  Which were then passed on to boring mills scattered around the area.

John Baird's book on Hawken rifles shows one made in the 1830s with a barrel stamped H REEDs Reading.  The stamp would actually be H Deeds.  Henry Deeds ran a barrel boring mill on ground close to what is now the Daniel Boone State Park near Reading.  This Henry Deeds was married into the Pannabecker  family who owned and operated a barrel forging mill in Mohnton.  The wrought iron skelp used to make that barrel most likely came out of Joanna Furnace near Mohnton.   After drilling the barrel was sold as 1 of a job lot of a dozen barrels to Hawken in St. Louis.  Carried by wagon into Reading, PA.  Place on a canal barge that went from Reading over to the Susquehanna River.  Then over to the Ohio River by way of another canal and then down the Ohio River and then on to St. Louis. 

Bill K.

Thanks Bill, fascinating stuff for sure. And interesting to me because I've been to some of the places you mentioned... I worked on the pumping stations on the Mariner East pipeline a few years back. My first stop was just south of Huntingdon (between Mt. Union and Shirleysburg) and my second stop on that job was near Beckersville just outside of Reading. I believe I actually did my laundry in Mohnton one Sunday afternoon.

I absolutely loved Pennsylvania. It was beautiful and I knew I was walking the same ground as some of the folks from my favorite period in history.

Mike

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: Barrel rupture
« Reply #40 on: November 15, 2019, 12:06:31 AM »
Whilst on a roll here.

Part of what constituted the "quality" of a barrel at that time was how it was forged.  Big difference in one that had been formed by hand hammering versus one made on a trip hammer.  That had to do with how uniform was the force of each hammer blow on the tube being formed.  There is an area outside of Reading, PA now known as Mohnton.  In the early 1800s there were 7 barrel forging shops along a stream in Mohnton.  All using water wheel driven trip hammers. Three or 4 workers to a shop.  Big forge where several barrels were being heated at the same time.  Just switching back and forth between skelps to insure the proper heating of the skelp. Constant hammering. Working from dawn until dusk. They could produce a dozen or more barrels a ay.  Which were then passed on to boring mills scattered around the area.

John Baird's book on Hawken rifles shows one made in the 1830s with a barrel stamped H REEDs Reading.  The stamp would actually be H Deeds.  Henry Deeds ran a barrel boring mill on ground close to what is now the Daniel Boone State Park near Reading.  This Henry Deeds was married into the Pannabecker  family who owned and operated a barrel forging mill in Mohnton.  The wrought iron skelp used to make that barrel most likely came out of Joanna Furnace near Mohnton.   After drilling the barrel was sold as 1 of a job lot of a dozen barrels to Hawken in St. Louis.  Carried by wagon into Reading, PA.  Place on a canal barge that went from Reading over to the Susquehanna River.  Then over to the Ohio River by way of another canal and then down the Ohio River and then on to St. Louis. 

Bill K.

Thanks Bill, fascinating stuff for sure. And interesting to me because I've been to some of the places you mentioned... I worked on the pumping stations on the Mariner East pipeline a few years back. My first stop was just south of Huntingdon (between Mt. Union and Shirleysburg) and my second stop on that job was near Beckersville just outside of Reading. I believe I actually did my laundry in Mohnton one Sunday afternoon.

I absolutely loved Pennsylvania. It was beautiful and I knew I was walking the same ground as some of the folks from my favorite period in history.

Mike

Near Reading is the Hopewell Furnace National Historic Site.  A restored iron furnace and village.  It has been a few years since we visited the site.  The gift shop had a very large number of books for sale that covered metal working technology of that period both in the U.S. and Europe.  I spent a lot of money on the books but priceless information was found. 

Bill K.

Anonymous

  • Guest
Re: Barrel rupture
« Reply #41 on: November 15, 2019, 07:00:18 AM »
Bill,
Thanks for some  history of iron and barrel making. This has always been of interest to me. Would love for someone to give similiar history of iron/barrel making in the southern states.
Dennisl
Interesting thread and the comment about southern states got me thinking about a visit to Birmingham Alabama a while back. Big local iron history with a number of museums that I spent some time at. Remember no mention of guns or gun barrel manufacture (would have peaked my attention), although the area seems to have hit it’s iron producing stride mid to late 19th century into the 20th century. Probably too late to have been involved with much muzzleloader barrel production.

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: Barrel rupture
« Reply #42 on: November 16, 2019, 05:13:36 AM »
Bill,
Thanks for some  history of iron and barrel making. This has always been of interest to me. Would love for someone to give similiar history of iron/barrel making in the southern states.
Dennisl
Interesting thread and the comment about southern states got me thinking about a visit to Birmingham Alabama a while back. Big local iron history with a number of museums that I spent some time at. Remember no mention of guns or gun barrel manufacture (would have peaked my attention), although the area seems to have hit it’s iron producing stride mid to late 19th century into the 20th century. Probably too late to have been involved with much muzzleloading barrel production.

I have never seen anything related published about down South.  The Mohnton barrel makers continued into the Civil War and they made a lot of barrels during the Civil War.  Some of the early bp cartridge rifles had trip hammer forged barrels.  There was some debate that the wrought iron barrels did not flex when fired and were thus more accurate.  Adds from that period in time show where a prospective buyer had a choice between a steel barrel and a wrought iron barrel.  As the barrel business dropped off  some of the trip hammer forges switched over to making files.

Bill K.

Offline Waksupi

  • Sr. Member
  • ****
  • Posts: 339
  • Ric Carter, Somers, Montana
Re: Barrel rupture
« Reply #43 on: December 01, 2019, 11:26:21 PM »
Bob:  in defense of Hall Sharon, the barrel's manufacturer, this rupture was caused by a second patched ball sitting a few inches above the first charge of pwder and patched ball.  The charge was likely in the neighbourhood of 80 gr. FFg and the second patched ball simply slipped back up the bore a few inches.   As you can see, the barrel failed right at the chamber area.  The plug itself remained in the standing breech tang.  Shane was standing at the far right hand end of the line of shooters and it sounded like a stick of dynamite going off.  We were having a team stake shoot, so loading fast and hard was the method.  We don't do that shoot anymore.

I remember when Blue Jacket, Jerry Cunningham and some others were doing destructive testing with Sharon barrels. I think the results were published in the old Buckskin Report many years ago. I seem to recall they loaded up to 1700 gr. powder, and 17 patched balls in a barrel, with no harm done.
They also took a paper towel tube, wrapped it in duct tape, put a wood plug in one end, and some sort of ball for a projectile. They loaded it with a horrendous amount of powder. No failure of the tube.   
The only way they could damage a barrel, was by separating the ball from the charge. I don't recall if they had any totally come apart, but do know they bulged several.
I personally have only seen bulged barrels, generally caused by the use of short starters. I don't use them. Fortunately I have never been around any that completely blew out. 
Ric Carter
Somers, Montana

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: Barrel rupture
« Reply #44 on: December 02, 2019, 03:48:00 AM »
Bob:  in defense of Hall Sharon, the barrel's manufacturer, this rupture was caused by a second patched ball sitting a few inches above the first charge of pwder and patched ball.  The charge was likely in the neighbourhood of 80 gr. FFg and the second patched ball simply slipped back up the bore a few inches.   As you can see, the barrel failed right at the chamber area.  The plug itself remained in the standing breech tang.  Shane was standing at the far right hand end of the line of shooters and it sounded like a stick of dynamite going off.  We were having a team stake shoot, so loading fast and hard was the method.  We don't do that shoot anymore.

I remember when Blue Jacket, Jerry Cunningham and some others were doing destructive testing with Sharon barrels. I think the results were published in the old Buckskin Report many years ago. I seem to recall they loaded up to 1700 gr. powder, and 17 patched balls in a barrel, with no harm done.
They also took a paper towel tube, wrapped it in duct tape, put a wood plug in one end, and some sort of ball for a projectile. They loaded it with a horrendous amount of powder. No failure of the tube.   
The only way they could damage a barrel, was by separating the ball from the charge. I don't recall if they had any totally come apart, but do know they bulged several.
I personally have only seen bulged barrels, generally caused by the use of short starters. I don't use them. Fortunately I have never been around any that completely blew out.

I used to have a pile of barrels here that came out of Dixons and had come apart in use.  All of the ones that were split or pieces were percussion ignition.  Never saw a flinter burst.  A few with rings where the short started ball was more than 4 or 5 inches off the charge when fired.  When you mention the old Buckskin Report articles on burst barrels I remember Sam Fadala and the copper pipe barrels he toyed with.  Both T/C and Lyman saw a number of burst barrels as a result of short start projectile firings.  And I remember the article in a chemical industry magazine that came to where I had worked.  T/C asked the university to prove that only smokeless powder could blow up one of their barrels.  I knew the article was a con job when I saw them switching back and forth between du Pont BP and Goex BP.  They would flush the failed barrel parts with acetone and then run the diphenolamine test on the flushings.  The idea being that BP was not soluble in acetone while smokless residue was.  Trouble is that Moosic made GOEX would always give a bright positive in this test because of the chemical decomposition in the Goex but not found in the older du Pont bp.  That formed part of my booklet on the Mossic plant I called The Critter Chronicles.  At the time the burst barrels were a great worry to the gun sellers nobody seemed to understand that what was going on in the short started barrel firings was the same thing that gives you what is called water hammer in liquid piping systems when you close a valve quickly. In the chemical plant we had guys blowing flanges off 4" stainless steel water charge pipes with the rapid valve closing.  There are times when bp is not as weak an explosive as commonly thought.

Bill K.

Offline bob in the woods

  • Hero Member
  • *****
  • Posts: 4535
Re: Barrel rupture
« Reply #45 on: December 02, 2019, 04:49:52 AM »
Thank you for that info , Bill.  I too believe that the goings on re a short started ball are similar to "water hammer"
I've seen 10 inch and even larger butterfly valves with banana like disc /shafts from water hammer.  I've also seen elbows [pipe] blown off.   That said, the vent in a flint barrel acts as a pressure relief , although not quickly enough to prevent bulging in some but not all cases.  One fellow at our club got away with many many " short starts"  until one day fate did not favour, and the barrel bulged .   I wonder if this was a case of fatigue in terms of the barrel material ?   

Offline RichG

  • Sr. Member
  • ****
  • Posts: 451
Re: Barrel rupture
« Reply #46 on: December 02, 2019, 05:58:29 AM »
If you study pressure tested data such as in the old lyman black powder manual the pressures with round ball loads are very low. Bullets are another story. As bores get larger the pressure are lower until you increase the charge to loads higher than most anyone would use. The larger bores have more area for the pressure to work on ,but the pressure are still extremely low. Most any barrel rupture I've ever heard about was because of mis-loading, smokeless powder , shallow dovetails etc.

Offline Daryl

  • Hero Member
  • *****
  • Posts: 15079
Re: Barrel rupture
« Reply #47 on: December 02, 2019, 09:21:40 PM »
RichG - I think you meant deep dovetails, as in thin metal remaining. That actually caused a bulge in a rifle I purchased once.
I was working up loads in it, an old Bauska .50 bl.  The load was at 85gr. 3F GOEX, testing on target at 50yards. After the third
shot with that load, the next went blip past the barrel wedge - felt the jump.  I pulled that load and went home, removed and
cleaned the barrel which displayed a bulge at the rather deep dovetail. I thought perhaps the pressure being lower at that location
would not cause problems. I was wrong. That 1/2 stock ended up with a .40 Goodoien barrel and is now owned by close local friend Len.
Daryl

"a gun without hammers is like a spaniel without ears" King George V

Offline Mad Monk

  • Hero Member
  • *****
  • Posts: 1033
Re: Barrel rupture
« Reply #48 on: December 03, 2019, 03:37:59 AM »
Thank you for that info , Bill.  I too believe that the goings on re a short started ball are similar to "water hammer"
I've seen 10 inch and even larger butterfly valves with banana like disc /shafts from water hammer.  I've also seen elbows [pipe] blown off.   That said, the vent in a flint barrel acts as a pressure relief , although not quickly enough to prevent bulging in some but not all cases.  One fellow at our club got away with many many " short starts"  until one day fate did not favour, and the barrel bulged .   I wonder if this was a case of fatigue in terms of the barrel material ?

When I was cutting barrels in half for Dixon I would start at the muzzle and saw right down through the breech plug.  One thing that caught my eye is that most short starters would seat the ball directly over a screw hole that held the under rib to the barrel.  After looking at that one I shortened my set f short starters.  That barrel I called the twice blown barrel.  Half stock percussion in .50 caliber.  Came over from New Jersey where the guy shot Pyrodex in it.  The first short start created a split in the metal centering on an under rib screw hole.  And I was shocked at how little metal there was between the base of the screw hole and the bore.  There was a lengthwise split centering on the screw hole that went about a 1/4 inch on either side.  Then a second short start with the ball in the exact same position as the first short started ball took the barrel in half lengthwise.  The amount of corrosion of the metal in the first small split showed there was some time between the two events.  But the first split was not real wide so the under rib hid it from sight.

A very interesting barrel in that the bore had been chrome plated by the barrel maker in Italy.  They had put out a bunch of these chrome plated bore barrels claiming it would end barrel rusting problems.  It was interesting under the microscope.  The electroplated chrome layers and split during the repeated firing of the barrel.  The chrome plating is very hard and very brittle.  So you had the base metal as regular mild steel that flexing during firing.  The chrome could not flex and just split up into tiny lozenges during firing.  Then each time you fired the gun some of the lozenges would blow out with the smoke from firing.  It gave shooting smoke that sparkled in the sun like you were shooting glitter in with the powder.  With the tiny splits in the 3 layers of chrome you still got powder residue rusting.  The swirling gases during the short start firing left their marks on the surface of the chrome in the bore. 

Bill K

Offline Daryl

  • Hero Member
  • *****
  • Posts: 15079
Re: Barrel rupture
« Reply #49 on: December 03, 2019, 09:47:57 PM »
Well, that's interesting, Bill. I remember hearing about those chrome lined barrels
& wondered how they worked, or didn't.
Daryl

"a gun without hammers is like a spaniel without ears" King George V