doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com The Southern Chamber Burst Gun

Possibly the braze failed allowing the lateral wall to "tin can" open? Obviously the barrel flats are very thick.




A 10g Parker felt to have a base wad obstruction with an asymmetric 'ring bulge' related to the addition thickness of the brazed barrel flats

A detonation. Always use best quality ammo.

Give Ted a cigar for being the first to note how thin the chamber wall is.

Give 775 a cigar for expounding upon that observation with more detail about the very thin area under the rib, and the dark spot where the big rip probably started.

I wonder if the owner of these barrels realizes that the guy he sent them to for analysis of the rupture is absolutely unqualified to make a determination of cause for this blow-up. Seriously, this is someone who was arguing several weeks ago that chamber lengthening in vintage doubles could result in GREATER WALL THICKNESS at the end of the recut chambers. It took a couple days with drawings and detailed explanations of the obvious to convince him otherwise. I'm pretty sure just mentioning this little detail will be used as evidence that I have acid and hate in my soul. Should be good for a Scripture verse or two. Maybe even a picture of Guatemalan kids or a dead dog.

There is no evidence that a "Detonation" occurred here. Detonation in the chamber of a gun would simply shatter it into smithereens. Detonations occur in High Explosives, not ordinary Smokeless Propellants.

"Detonation" can occur when a smokeless propellant is used in a manner not suitable for the application. Detonation with smokeless is hard to "pin down", but usually occurs when a small charge of slow burning propellant is used in a case that allows a lot of empty space where the propellant is housed, like a centerfire rifle case ............. not likely with a shotshell.

SRH

It appears to me that pressure sufficient to cause this failure was applied to the full length of the chamber.

The entire right side of the chamber is bulged out and levered by the flats where a crease is evident.

This one has a different look to it than some others we've seen here.

re: detonation
Short version
Detonation of smokeless shotgun powder HAS been demonstrated experimentally
Detonation of smokeless shotgun powder in a shotshell have NOT been demonstrated
Long version
http://www.trapshooters.com/threads/smokeless-powder-ddt.245629/

IMHO this is the result of detonation. The remains of a Perazzi MX8

re: 20 in a 12 burst. This may have been one. Long aneurysmal bulge with burst and burst forward of the obstruction



re: expertise. It doesn't take a lot of brains or talent to record wall thickness numbers; just the equipment and practice therewith to establish repeatable numbers and the willingness to spend the time to do it right; and it does take time.

Correct- in most cases, and overloaded shell can be the culprit- RWTF

I recall reading about all those big magnum rifles which could be loaded with a compressed charge of a slow burning powder such as 1831 which was very popular in that era. Then it seems some folks wanted a reduced load so as this was then a surplus powder & available at extremely attractive they just cut back & loaded about a half charge. Most of the time everything went OK but on occasion, one would get a blown up gun. A lot of p[eop;e started hollering Detonation from all the exposure of the charge to the primer flash. Ballistics labs could not reproduce any high pressures at all & some went so far as to say this simply could not occur & had to be from some other cause rather than loading the light charge.

Rifles, however, continued to blow up. Investigation finally proved it was actually a failure of the slow burning powder to properly ignite with the primer force pushing the bullet into the bore & when the powder then caught the bullet itself acted as an obstruction. To the best of my knowledge, it was proven beyond doubt none of these bursts had been due to detonation.

Many feel that a lot of the early burst shotgun barrels when the switch to smokeless came in was from a similar cause. It took a while to realize the primers which were successfully used with black were simply not sufficiently hot to ignite smokeless resulting in an ignition lag. Damascus, of course,
became the ScapeGoat.

So yes under some conditions it is possible to get a "Detonation" with smokeless pro[pellant, but I would have virtually no concern of it happening inside a gun barrel. Plus like I said a detonation would not have just split the chamber, it would have made shrapnel out of it. With a true detonation, there is no such thing as a slow burn or fast burn, the entire charge simply GOES as one. It needs neither a projectile in front nor an overcharge to totally shatter the chamber. This is NOT the condition I am seeing in this gun.