Blow up puzzler

Using reloads?

If using reloads, were the cases trimmed to the correct length? Overlength cases can be bad news for pressure. I've had several customers with blow outs using reloads. When asked about case length/trimming, one fellow didn't know what I was asking him about.

Just a thought. Hope you get to the bottom of this mystery. Joe
 
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I blew the action apart on a lever action marlin 45/70 years back. Trying to get the max and not measuring individually w/ fast powder. He needs to back off a bit.
 
Where safety is concern

There is no substitude for a bolt with a nose. I solely blame the brass. Someone I know was spotlighting and his Sako .243W came appart.The barrel was found the next day 20metres away, the magazine floorplate was rolled, the scope hit the roof of the inside of the 4WD cabin and he also had few minor burns, splinters and scratches in his face and forearms. Very lucky indeed.

Shoot well
Peter
 
Brass Q?

Is he using the same brass over and over again?
If he is over sizing the shoulder back each time them stretching it when firing maybe that could lead to case thinnning/stretching failure, maybe.:confused:
 
I have to wonder about the bullets. Some newer reloaders think that XX grain, XX cal. bullets are all the same even different styles of the same weight from the same manufacture and even between different manufactures. There can be a great deal of differences like bearing length, jacket hardness, ogive etc. A blunter ogive will cause jam into the lands at the same overall length as a longer ogive that gave some jump. Bearing length has a dramatic effect on pressures as does the hardness of the jacket. I have had customers present rifles and handguns following an episode of “over pressure” or “hot load” and upon discussion it was determined that the cause was; they ran out of the bullets they used to developed their “near maximum” load with and wanted to finish reloading their empty cases so they acquired different bullets and finished up. The reloads were mixed together and away they went to go shooting. You know the rest of the story even without Paul Harvey. Upon examining the remaining reloads it was apparent the shape of the bullets was different. Pulling the bullets and weighing the powder revealed the same weight of charges and the cases were of the same manufacturer although the lots were unknown. I surmised that it must have been the bullets even though I did not check case volume or length.

Individual results may vary,
Nic.
 
I think Gunsmither is probably on to the problem with a long case neck. Measure the overall case length and I would bet that some of them are to long. I load a lot of 223 and they grow a lot with max loads. My lapua cases need triming after 1 reload some times with just neck sizing.
 
Might be picking nits here but it sounds like an overload as others have said. The guy says he measures each load. Maybe. Does he use a powder measure? Probably got one light load and the next was an overload. He might just confess!
 
I'm lost :)

I'd jump in with Kobe on this one, the powder bridged due probably to low humidity and the guy sent part of one charge into the next case. Twice. BUT......BLC-2 is BALL powder. . . . ???? can't really bridge can it?

I can't get behind any of the seating depth/rounds getting heat soaked/different ogive stuff nor even the alligatored bore because none of these are this catastrophic IME. Rounds setting out in the sun yes, rounds worked up in the shop and then left on the pickup dash for an hour yes, but these rounds were normal except for two. And there's absolutely no way that a round can gain enough chamber heat to do it. A case separation at the web from over sizing is 'way too far forward to be it, and an entirely different rupture pattern.

A neck that'd grown so long that it crimped on the bullet could do it, he'd have to be levering the bolt down perty hard not to notice it.



Is there any chance that this guy left his rounds setting on the wood stove maybe or otherwise somehow annealed the caseheads? If the bag of brass was setting too close to the fire.......... I mean it's a STREEEETCH but I'm with you Dennis, it looks like catastrophic casehead failure. It's obviously not a clearance issue from the photo of the thin web of extruded brass.....



Dennis I'm kinda' leaning toward your theory.............too bad you can't check the brass for hardness after she's blown eh?


I hope you get this one figgered....



al
 
SooStan,


You're missing something in your reloading process or your chamber's buggered. It's physically impossible for brass to grow from just neck-sizing. The mechanism simply does not exist when you neck-size only.


al
 
You might ask how he is cleaning his brass. I've seen too much polish in the tumbling media (too wet) cause just enough ground walnut or whatever to stick inside the case, reducing volume---major overpressure even with a consistent powder charge.
 
Dennis

Virtually every blow up posibility was mentioned here so lets see if the rifle will come back to you again.

Shoot well
Peter
 
PPP MMM said:
Virtually every blow up posibility was mentioned here so lets see if the rifle will come back to you again.

Shoot well
Peter
Click to expand...

Well as far as I am concerned everything except the hardness of the brass is eliminated... hopefully he doesn't blow another one... I told him I would not use any of the Winchester brass he has... but he has a lot of new brass and I am sure he is going to use it... he will be in touch one way or another... I'll update this post if I hear anything...
 
Dennis,
If I was him, I would go through the entire lot of brass and measure the distance to the web. It certainly looks as if that particular case was too thin. I measured a bunch of Winchester 223 brass and the distance from the base to the face of the web was from .186 to .190. If the bolt face recess is .150 deep and the clearance is .005 ahead of the nose, you would still have about .030 in the barrel. You would likely lose about .010 of that to the bevel so you are down to .020. If the bevel is a little excessive and you have brass which is only .175 at the web, the occasional piece of brass may lack support. With a fairly stiff load, it could fail.
As many may recall, this was the problem with the use of Remington actions for the PPC back in the 70's. The Sako brass was thinner in the web and the amount of protrusion necessitated by the depth of the Remington bolt face left too much of the case unsupported. This was one reason for the change to other extractor systems; the bolt face recess depth could be decreased to .125 or even a little less. Cartridge protrusion was reduced. In either case, one had to be careful not to go overboard when breaking the edge at the chamber mouth. Regards, Bill
 
Bill Leeper said:
Dennis,
If I was him, I would go through the entire lot of brass and measure the distance to the web. It certainly looks as if that particular case was too thin. I measured a bunch of Winchester 223 brass and the distance from the base to the face of the web was from .186 to .190. If the bolt face recess is .150 deep and the clearance is .005 ahead of the nose, you would still have about .030 in the barrel. You would likely lose about .010 of that to the bevel so you are down to .020. If the bevel is a little excessive and you have brass which is only .175 at the web, the occasional piece of brass may lack support. With a fairly stiff load, it could fail.
As many may recall, this was the problem with the use of Remington actions for the PPC back in the 70's. The Sako brass was thinner in the web and the amount of protrusion necessitated by the depth of the Remington bolt face left too much of the case unsupported. This was one reason for the change to other extractor systems; the bolt face recess depth could be decreased to .125 or even a little less. Cartridge protrusion was reduced. In either case, one had to be careful not to go overboard when breaking the edge at the chamber mouth. Regards, Bill
Click to expand...

Actually I cut some of the fired brass and some of the new brass length wise and draw filed the edge and had a good look at it... the web seemed very normal and would be well within the chamber... mind you, that is on undamaged brass... who knows if there are more lurking?

Here is a picture typical of the brass I sectioned...

"B" would be at the edge of the chamber...
sectioned%20case.jpg
 
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alinwa said:
Roger that's some perty good thinkin' right thar! I'd never heard of that one.


al
Click to expand...

The pic's on the first page look exactly like a prairie dogger's .223 that blew last summer, I've got a swelled rim on SA 700 bolt from a .204Ruger that also had walnut media in stuck in the case (found after checking the remaining loaded ammo). I'd pull the bullets on the suspect loads and check everything out. Corn cob and walnut media weigh very little so it's hard to find the problem cases by weighing loaded round but if he's got a thousand loaded through his Dillon I give the weighing a try. Bench rest guys never have this problem!!
 
Don makes a good point.

I hope that this fellow has some shooting glasses by now! If he does not, I wouldn't trust his judgment or accounts of what has been done to what.
 
Once I pushed a load until it was too hot, in a .223. I had 20 rds this way. But, it was a nice day and the gophers were up so i shot them anyway. They blew the primers out and swaged to brass to the boltface. I pulled the bolt after each shot and knocked the brass off against a rock, I got 20/20 gophers. The only thing i had to do was replace the extractor. This was good brass, and had never given any problems at a couple of grains less with the same powder. My point is, there's something going on there besides a simple overload. Back in the day when we regulalry hotrodded our loads, it was routine to increase until you lost the primer then back off just enough so that you didn't. 70kpi was normal. The failure you describe was caused by something else and is running way over 70kpi.
 
One observation is the flash hole evenly enlarged. If the brass was not soft, would that be possible given the rest of the results?
 
17 Remington

Just had exactly the same thing happen to me yesterday with a 17 Remington, with 700 Remington action. Damaged the bolt face enough that the extractor (half moon spring is only half secure in the bolt face. Just had the barrel and action fitted a month or so ago and have fired more than 100 rounds through it of varios loads. Accuracy goo (sub 1/4 inch) and was half way through a 5 shot group of 22.6 grains of VVN135 with a 30 grain berger bullet. One thousandths of the lands. All cases trimmed and subsequent loads taken apart and re-weighed to verify goods load data. They were fine. The casings were loaded 10+times (FL sized). Have placed the prior round back into the action/bolt and started applying tape (all I have to ascertain what the head space may be) and I got a single piece of white medical tape onto the bolt face and was able to close the bolt with some pressure, but would not close with two thicknesses. Whadathink? No heat soak (45 degrees outside). Liuckily I was wearing glasses as the debris did come back in my face. Unhurt! New bolt or repair possible?
 
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