Final Exploding Taurus Judge Thread With Probable Solution

[35remington]

Regardless of how the high pressure happened, that very high pressure was present you may regard as pretty much absolutely confirmed.

[jonp]

You double charged one round. That is all it takes.
You are not infallible.

Some rinky dinky problem like seating depth did not blow the top strap off of the frame. You had a gross over pressure event.

This might be where we end up. Gross pressure event without a doubt, i think but from a double charge or pressure spike due something else combined with gun design?
I have been unable, so far, to find a picture of a overpressure event causing cylinder destruction that did not also include brass destruction. The brass is dented inward not outward suggesting overpressure in front of the case not in it.

[dverna]

HP White Laboratories can pressure test your loads to determine how much a change in seating depth affected your loads. I think it will not show as much of a pressure difference as you may believe but it will answer that question definitively. They should also be able to test the double charge theory and render an opinion if a double charge would have caused the damage you sustained.

They will provide a quote so you can decide if it is worth it to you.

I suspect by now some of the most knowledgeable and experienced members on this site have responded either on this thread or by PM. It may be time obtain data to discount or support the opinions you have received.

One last item....have you contacted Taurus and have they made any suggestions?

[glockfan]

one thing is for sure : when playing with max loads,any kind of bullet set back is able to create an ''atificial''' double charge effect. in this case,i doubt the bullet went back into the case enough to create an ''artificial''' double charge,while anything is still possible.

[john.k]

My suggestion is that the cylinder failed firstly into the arbor hole ,thereby denting the case inward,and splitting the cylinder along the plane of weakness that caused the initial failure.There is a principle of crack propagagtion,whereby force applied into the cracking surface is many times the failure strength,and large ammounts of energy are applied into the propagating crack.This is the cause of catastrophic boiler explosions which turn 1/2" thick boiler plates inside out like they were origami.

[HangFireW8]

I have been unable, so far, to find a picture of a overpressure event causing cylinder destruction that did not also include brass destruction. The brass is dented inward not outward suggesting overpressure in front of the case not in it.

The headstamp and the inward dent are our biggest clues.

The headstamp mark could indicate a huge overpressure, but it could also indicate the base being driving backwards at high speed. High speed would require... clearance, room to move, time to pick up speed.

The inward dent... a little background. Bolt action rifles regularly take loads up to 62K MAP with zero problem. Yet when the brass uncorks near the head, it blows their receiver ring apart. Why is that? The vented gas actually has lower pressure because it's venting into a larger area. Yet the receiver ring shatters. Why? Because the pressure is applied across a larger area, that was not intended to take it. The receiver ring behind the breech and ahead of the locking lugs is actually rather thin, anyone who has tapped one for a scope has probably noticed this.

So getting back to the revolver, that inwardly dented brass case indicates gas was getting into places it shouldn't, because of a.) unknown event, and b.) the gasket (brass case) was compromised. We also have a revolver, which has failure (and pre-failure) modes that bolt actions and automatic handguns just don't have. So I think the answer is in there, somewhere.

[HangFireW8]

jonp, some questions: were the cylinders oiled, or dry? Likewise, were the cases still lubed from case lube or boolit lube, or dry and clean?

[35remington]

What is very obvious is the creased case did not come from the chamber that burst.

[NoZombies]

I don't mean to offend, and I appreciate the efforts you've gone to in trying to piece this together, but the type of failure you had was not from marginal overpressure, even if there was an issue with the metallurgy. This was a massive overpressure event, most likely caused by a double charge.

[Thundarstick]

Following these three threads, one thing I've missed being mentioned is the possibility of a detonation, where a partially blocked flash hole allows the bullet to be blown forward onto the cylinder/ throat, then the dispersed powder being ignited in a detonation.

[HABCAN]

I think the blown case is missing, GONE, and the one you show is an 'adjacent' one. I also think that it's a typical (??) Taurus structural metal failure. Further, I agree with 35Remington's posts. I may be wrong: I've just read the posts in this thread. I wasn't there.

[Bazoo]

I havent followed the other threads mentioned as I didnt come across them. Im glad you werent injured.

The simplest answer is normally the correct answer, and that points to a simple double charge. With the brass not acting as you would expect from a double charge... well, things happen. Imprinting of the headstamp is an indicator in the right direction.

I was pondering. Is it possible you might have had some foreign object in the case which increased capacity or raised the pressure? Maybe an empty case of a smaller caliber such as 9mm or 40 s&w. Is it possible that you had a 40 casing in your 45colt casing and then sizing the colt, punched through the flash hole of the 40, then, punched a hole in the 40's primer, and then popped out the 45's primer as normal? Not likely But.. its an idea I had.

[HangFireW8]

On Request, using QuickLoad...

Holding a Lee 452-252-SWC at 1.545" COAL:
17.6gr Unique gives 77240 PSI.
13.05gr Unique gives 40108 PSI


Holding an 8.8gr Unique charge steady, and reducing the Lee 452-252-SWC seating depth:
1.545" COAL gives 18159 PSI
1.285" (flush with case mouth) gives 36540 PSI
1.260" (below case moth) gives 40657 PSI
1.1" gives 160633 PSI (This is most likely wrong, see below)

Forum member and noted overpressure expert clarkm has noted to me in personal communication that for gross overloads and beyond-edge cases, QL tends to overestimate pressures... but it remains correct in noting that the pressure is an overload.

[tomme boy]

People! READ Hangfires post in post #46 very carefully. You will have your answer.

That chamber had a defect before the trigger was pulled.

[dubber123]

Jon, did you get as chance to count the new batch of Starline brass to see if one was missing? Every single thing about your incident mirrors every other high pressure blow up I have seen, EXCEPT that piece of brass. If you come up a piece short, and I'm beginning to think you will, you have your answer. The piece of brass that was involved with the blow up is still circling the earth along with your top strap.

Thank you HangFireW8 for running Quickload. That's more pressure than I was expecting, almost enough to uncork a 44 mag Ruger SBH. Plenty I'm betting to do a Taurus in.

[HangFireW8]

You're welcome.

Now I'm re-reading my post #46 looking for the answer.

Jonp the ball is in your court, what's the word on brass count, location of the inward blown brass, also my questions on lubed chambers/cases?

[buckwheatpaul]

jonp you did a great job and I think you hit the nail on the head....just glad you were not hurt and your pictures and others suggestions plus your investigation should serve as a warning to watch your components and tools.......Paul

[dubber123]

The bullet(s) did not come out of the case and tie up the gun. The only other way they could have gone was in. All bullets are uniform but the other explanation is I could have seated one just that much deeper as a variance on seating depth which would have been enough to cause the explosion. Just as probably.
I'm discounting the double charge theory for the reasons above. Hand weigh, inspection under a light, moving each brass one at a time from the seating tray to the shell holder, placing each boolit into the casing. Just too many steps to miss one that was full almost to the brim. A double charge of Red Dot or Bullseye sure but not Unique

Jon, there just isn't a possibility of one getting driven into the case, it's just simply the opposite of how it works. It COULD have gotten pulled out, and given the length of the cylinder, you could probably stack two in front of the case mouth and still not tie up the gun.

There has been some mention of seating depth, but unless the brass was SIGNIFIGANTLY trimmed, your seating depth was fine, as you stated it was seated to a crimping groove which puts you in the safe ball park as far as seating depth with the boolit you were using.

[reddog81]

So getting back to the revolver, that inwardly dented brass case indicates gas was getting into places it shouldn't, because of a.) unknown event, and b.) the gasket (brass case) was compromised. We also have a revolver, which has failure (and pre-failure) modes that bolt actions and automatic handguns just don't have. So I think the answer is in there, somewhere.

Cylinder steel is stronger than brass. What part of the cylinder can't handle the pressure of a 45 Colt load? The cylinder in question blew through 3 chambers and took off the top strap.

I agree that the dented brass was probably from an adjacent charge hole. It's my understanding that the top strap was never found - I'm guessing the brass from the charge in question also went flying.

FWIW there's no way a .45 Colt bullet seated deeper into the case under recoil. Revolvers act like a bullet puller and the bullet loosens from the case if there's any movement. Additionally .035 is not going to have any substantial effect on a .45 Colt load. Look at the bearing surface length of various molds they routinely vary by more than .035.

[35remington]

The more complicated one makes an event in order to explain it, the less plausible it becomes.

For the reason that multiple implausible things happening simultaneously become more unlikely with every layer of complexity added.

The simple fact, which is the best fact, is that very high pressure was involved. Discard any theories that do not include that as a central premise. Then look for the least complicated reason high pressure would occur. Better analysis is the result.