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Posted By: gunut Perazzi blow up - 05/26/08 02:10 PM
Did any of you see the pics and story in the gunsmithing section of shotgunworld.....scary/impressive...man..
Posted By: Drew Hause Re: Perazzi blow up - 05/26/08 03:03 PM
Here's the thread
http://www.shotgunworld.com/bbs/viewtopic.php?t=145333
Posted By: gunut Re: Perazzi blow up - 05/26/08 03:25 PM
Thanks ....some of us old coots dont know how to do that...and dang it we dont care to learn how....
Posted By: JayCee Re: Perazzi blow up - 05/26/08 03:31 PM
Scary stuff indeed! The owner of the gun should get several lotto tickets.
The pressure must have been enormous.

JC
Posted By: Anonymous Re: Perazzi blow up - 05/26/08 03:40 PM
All that damage with a very light load! I didn't know modern smokeless powders could be made to detonate.
Posted By: GregSY Re: Perazzi blow up - 05/26/08 04:30 PM
I think it serves to illustrate that 1) it is unlikely a gun will blow up and 2) if it does, it is unlikely you'll get hurt.
Posted By: Salopian Re: Perazzi blow up - 05/27/08 06:32 AM
Gregsy, without wishing to appear rude, arrogant, and to admonish you that is a very cavalier attitude.
Gentlemen could I please ask someone over there to carry out some research into just what you guys are doing wrong over there?
I have travelled the World and shot in most of the Countries and Continents and I do have to say that blowing up guns seems to be an exclusively American party trick.
If it is of any use in your research may I relate an incident to you?
A friend bought a new Remington Auto from Hull Cartridge Co who used to be the importers.This gun had many problems and broke many parts around the breech and bolt area and mechanismn.Hull were concerned about this and after the 'enth number of guarantee repairs asked him to bring his usual brand of shell with him which happened to be Winchester Blues.
On testing a box of 25, EVERY cartridge was over pressure by a considerable amount, in Hull Cartridge's opinion.Gun was repaired, cartridge brand was changed (not to a Hull brand) and that gun never had another malfunction.
Does anyone know of a gun blowing up using Factory Ammo? Using European loaded Ammo?
We really do need to explain this, before someone gets seriously hurt.
Although I do know personally a few people who are bearing the scars or missing the thumbs or fingers from such incidents.
I do not think the thread on 'shotgunworld' is conveying the seriousness of these incidents. It is not incredulous, it is down right scary.
Posted By: Mike Bailey Re: Perazzi blow up - 05/27/08 10:34 AM
I agree Salopian, I cannot believe a Perazzi blew up with a normal factory load. They are renowned for being almost bullet proof. Something wrong in that shell.
Posted By: smlekid Re: Perazzi blow up - 05/27/08 10:39 AM
Salopian you make some very interesting points I no longer use ammunition loaded to SAAMI specs through my guns I much prefer the lower pressure CIP loads and my own low pressure reloads
I don't see the sense in using loads that devolep 10000-11000 PSI when I can be using loads around 8000 PSI for the same velocity
Posted By: GregSY Re: Perazzi blow up - 05/27/08 11:47 AM
I have that viewpoint as I have read on this BB and others a fair number of rifle and shotgun blowups and I have yet to read of one where the shooter was seriously hurt. I'm sure there are instances, but statistically they seem to be in the minority.

What I read a lot of is 'Oh My God, I could have been killed!" which is not the same as Oh My God I was killed." If that makes me cavalier then I don't care.
Posted By: KY Jon Re: Perazzi blow up - 05/27/08 12:27 PM
I have seen exactly one gun let go with factory loads. It was a K-80. The owner never reloaded and was extremely good about keeping his almost new gun in factory original shape. Much debate and hand wringing at the time never concluded the real cause. But he did get a new barrel and for end stock put on the gun by the maker. Not that they assumed any fault. Just to make him happy.

Most gun failures, when it is not the guns fault for being rusted out or pitted to a weak point, are the reloaders fault. If your gun is weak any shell could cause a failure. Most guns are in solid shape and take that extra measure of pressure or extra measure of dumb to make them fail. Get a base wad stuck in the barrel and they might fail. Use the wrong powder and they might fail. Use the wrong bushing and they might fail. Almost all gun failures are induced by the shooter by his error in my opinion.
Posted By: eeb Re: Perazzi blow up - 05/27/08 12:59 PM
The poster on Shotgunworld indicated the gun was " a 25 year old over-under Perazzi that has shot hundreds of thousands of rounds", which begs the question, at what point do you retire a gun? Also his load data is not what I would call a mild one, but he did say he used a PW press which reminds me of that long thread here a couple years ago when the poster blew up a pristine Baker. He used a PW press, and Clays powder, but what happened to that P-gun was unreal, not just a blown out chamber but total destruction. It had to have been the perfect storm: overload, stuck wad, weakened chamber. WOW.
Posted By: Dick_dup1 Re: Perazzi blow up - 05/27/08 01:01 PM
Failure analysis cannot be conducted over the Internet by viewing pictures. It takes a trained Metalurgist, the neccessary equipment to first view the fracture surfaces under high magnification, then cutting of test specimens to verify the metalurgical properties of the material along with calculations and assistnace from both the gun and ammunition manufactures.
Since the shooter had mixed factory and reloads in his pocket, the highest probability is faulty reload. without conducintg a full scale failure analysis and knowing exactly what type of ammunition was involved it is not even useful to speculate, 'Pet Theories included.-Dick
Posted By: eightbore Re: Perazzi blow up - 05/27/08 01:43 PM
This blowup, like absolutely every other one reported on the internet from the time of Al Gore's birth, involves a shooter who has lost or discarded all evidence that would explain the accident. This is not meant as a criticism, just a statement of facts. Weird, huh?
Posted By: Rd Show Re: Perazzi blow up - 05/27/08 01:44 PM
Here is anouther one that blowed up with Rem. factory loads. There has been several court hearings over this and test by Rem. this happened at a local club. Bill the owner is in his eightys and not in good health so i haven't persude it receintly. He was not injured when the gun blew up. Rich [img][/img]
Posted By: Chuck H Re: Perazzi blow up - 05/27/08 01:47 PM
No matter the root cause of the failure, the photo evidence indicates the event involved extreme pressure at the chamber. I'm guessing the pressures were above where the Bell Parker blew.

Someone on the other bbs suggested the metal wasn't ductile enough. Sheeesh! Look at all the deformation and chamber swelling. Another suggested a pre-existing crack caused this. Then why all the deformation and that fracture face? Why the split reciever?

I agree with Dick that you can't conduct a failure analysis based on pics across the internet, but these things are evident in the pictures.
Posted By: Salopian Re: Perazzi blow up - 05/27/08 02:40 PM
Gentles,
I was never pointing the finger of blame at anyone, especially Gregsy.What I was trying to convey is that this problem of blowing up guns seems to have an exclusively American membership.Is that not good reason to look inward?If I can save one gun and one finger it will have all been worthwhile.I am not impressed when I visit your shooting grounds and men show me their scars and the piece of shrapnel that they keep in the glove box that did the damage.Impressed I am not.Horrified I am.
Posted By: NiklasP Re: Perazzi blow up - 05/27/08 03:25 PM
In discussions on this board of blown shotguns one often reads mention of factory ammo loaded to SAAMI vs CIP regs vs "low pressure" reloads. There is actually a 4th class of chamber pressures, what I will call "hot latino" loads. Here I include at least one Rio and one South American loaded Imperials, both in 67 mm 16 gauge hulls. In two instances, when submitted for measurement of chamber pressures and near-muizzle velocities, pressures were in 12000++ psi range and velocities about 1400 fps. How common are these high pressure loads?

At various times I have seen 12, 16 and 20 gauge Rio target ammo at attractive prices at trap and skeet clubs. Did all these Rio ammos also produce such high chamber pressures? Anyone have instrument pressures and velocities for Rio 12 and 20 gauge loads. They were sure popular. I also have reason to think (but not to conclude) that both Rio and South American Imperial shotshells are provided to foreign dove shooters enjoying those thousands-of-rounds-per-weekend shoots. Just how many of these "bullet proof", high dollar trap guns were subjected to unknown thousands of these hot latino loads?

Once one gets away from areas where shooters are native English speakers or Central Europeans, what is record of blown target shotguns and what are typical chamber pressures of factory ammos?

Niklas
Posted By: AmarilloMike Re: Perazzi blow up - 05/27/08 03:27 PM
Being an abesent minded kind of guy I am always worried I am going to swap powders. I am going to use a bulky powder receipe and accidentally load a dense powder. I have a Rex III low pressure sixteen gauge recipe and I use a MEC 33 powder bushing - if I remember correctly. My fear is my dumb ass is going to load Longshot by grabbing the wrong powder jar when I meant to load RexIII. When I load Longshot low pressure reloads I use a MEC 16 bushing.

Now I have a clearly marked jar for each powder but...

Best,

Mike
Posted By: Shotgunjones Re: Perazzi blow up - 05/27/08 05:23 PM
Hey guys... the discussion of SAAMI, CIP, reloads, etc is really not relevent to what we observe with these blowups. If Bell's tests showed anything, they show how tough even old guns are. The recent blow ups I've heard of involved some really fine modern guns, all proofed by either government agencies or the maker to at least 150% of normal pressure. It's likely that the guns will stand double, or greater, normal pressure before any signs of damage. They don't and shouldn't "blow up" with any reasonable load and most that are well past reasonable. I doubt that ANY quantity of correctly functioning modern smokeless shotgun powder that could fit in a shotshell would cause what we observe here. They usually survive even the dread 20/12 accident without the chamber failures we are seeing.

What we see is a detonation. The powder is not buring smoothly and progressively, it's releasing it's energy all at once. Like a grenade. The pressure spike is obviously enormous. This is an explosion to be sure... something is taking the shotshell out of it's normal operating range and turning it onto a bomb.

The story of the 101 on the Shotgunworld thread has my attention. Note the 'delay' before the gun detonated.

Have any experiments been conducted to simulate 'double ignition' of shotshells? The scenario I'm thinking of would be a faulty primer that burns in two phases. Phase one simply heats the powder charge up, phase two very shortly after ignites what is then a preheated charge. Is it this or something similar that causes detonation?

Perhaps someone with industry experience will comment.











Posted By: Chuck H Re: Perazzi blow up - 05/27/08 05:54 PM
Jonesy,
My reading on the subject of detonation suggested that it occurred in large capacity cases, like rifle cases, where the charge is small in volume and the powder lays lower than the flash hole when the gun is horizontal. This seems to suggest that the same phenomenae is not possible in a shotshell where the powder is compressed and all unfilled volume is eliminated by the wad being pushed down and the shot/crimp restraining the wad.

If there are other causes of detonation of properly made smokeless powders, I'm not familiar with them.

Nevertheless, it's not apparent to me that the gun had any deficiency in the Pgun blowup.
Posted By: AmarilloMike Re: Perazzi blow up - 05/27/08 08:42 PM
No pictures but here is another one on Shotgun World:

http://www.shotgunworld.com/bbs/viewtopic.php?t=145063
Posted By: Jakearoo Re: Perazzi blow up - 05/28/08 12:00 AM
Well, one thing is for sure. At least one person did something very wrong to get there. Could have been more than one. RCC
Posted By: Jimmy W Re: Perazzi blow up - 05/29/08 06:29 AM
Looking at the primer shows that it is a reload. If he had just shot a double, it's quite possible he didn't hear the shot to hear if there was any "strange noise", so there could have been a wad stuck in his barrel. He didn't know for sure if there was an obstruction because he didn't check his barrels after he shot. Bad mistake on his part. He also mentioned that he had just replaced the triggers, so he, (or someone) could have goofed something up causing the gun to double. Hundreds of thousands of rounds through a Perazzi isn't that much if he takes care of the gun. On the other hand, I have been lamblasted on here before for saying so, but I never cared that much for them or the steel they use. But that's an awful lot of distruction for a double charge. Even for a Perazzi. I'd guess he had an obstruction.
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