What are the definitive specs for in out of battery for a glock, regarding oob firing

[Dixie Gunsmithing]

Unclenick, I figured that might be what was happening with lead ammo, where the fouling caused a rise in chamber pressure. I've never seen anyone state that, though.

Usually, when I see questions about reloading and used brass, with a case rupture in pistols, there only a few things that can cause that, and a barrel unlocking from the slide is not one of them, unless it was a catastrophic failure that they were speaking of. With a delay built into all locking pistols, the bullet should have been long gone, and the pressure dropped to nil, before the barrels locking lug comes out of the slides recess, and before the breech face ever starts to part from the rear of the cartridge for extraction.

 

[briandg]

I am back from a very long range session with a rifle. Some observations

First in the first hundreds of rounds our of that ammo can nothing showed high pressure, and as I've said, I'm ruling out simple over pressure. Not a single one of the ones I left at the range showed any abnormalities, either. No bellies, no primer flattening, nothing unusual that I could see. It's incomprehensible that I could have dropped an excessive charge. Btw, I need to go back and edit, it wasn't aa nine, nine is the ammo. The powder was aa two, still not the ideal powder, but recommended. I'm going to look at power pistol for that load, as I already have a jug.

The rest of it comes back to the actual blowout. The case still slides into the chamber with just a little force. The tear started on the side, where the case is better supported, and peeled to the right, along the chamber mouth. This isn't at all what I've seen on all of the information available. They blow in the belly, not in the web. I'm convinced at this point that it was bad brass, with some possible aggravating circumstances. I'm going to try to get some pics taken and posted, but it's hard getting details.

The rifle was disappointing. It's a .243 700, moa capable, but I replaced the scope with a hunting scope, nd the cross hairs completely blocked the target. Got a couple at 1.5 and others at two or so

 

[45_auto]

I had laid up a target, returned to my shooting point, and fired a round. I forgot to put on my ears and eyes. Three rounds later, ka pop.

I have a checklist I follow for things like this, but one day found myself at my destination without my pistol.

Can any of you guys imagine staring at your range bag for five minutes minutes, trying to determine whether you have everything, then going over the checklist, and finding out later that you left home the ammo for the second pistol? Oh, yes, the list said "ammo" nd there are .38 rounds but no rifle ammo, nor a spotting scope.

It's incomprehensible that I could have dropped an excessive charge.

You forget your safety glasses and ear protection (despite firing four rounds), you forget your pistol, pistol ammo, rifle ammo and spotting scope despite having a checklist, but it's incomprehensible to you that one of the most common mistakes in reloading could happen to you?

Have you ever considered reloading with a friend?

Doesn't seem like there's much point in continuing this discussion, sounds like you have it all figured out - good luck!

 

[James K]

Those are fine drawings of the 9mm cases we are used to. But I have seen imported 9mm and .45 ACP cases which are basically the old balloon head, with deep spaces between the primer pocket (which is sitting well above the solid base) and the side of the case. Those case heads are adequate for normal pressures, but are significantly weaker than the solid heads we are used to seeing and which are depicted in the drawings.

AFAIK, no American maker currently uses that kind of case construction, but it is used when expense is a factor, i.e., in cheap ammo.

Jim

 

[Dixie Gunsmithing]

Jim, I've seen that myself. Google photos has some good cut-away views of the 9mm imports, and they have a groove in the bottom, making them much thinner, thus it is by the manufacturer, and what material they use, and how they draw the case. Combine that with the Glocks chamber design, what ever that may be, and one might see a blow out after a few rounds of reloads. Of course, one might see it too, in other pistols just the same.

I don't know how true to scale the CAD drawing was, but at least one US manufacturer, Hornady, shows the case being about the same thickness all the way down, unlike the Israeli ammo in the drawing above, that has a tapered sidewall. I think pretty much all US manufactured ammo has a tapered sidewall.

Copyright (C) 2016 Horandy.

Photos Copyright by Sabine Pearlman

I'm not sure who the daddy of the one below is, as it is on Printrest. However, it shows an awful thin base, if the drawing is correct.

 

[briandg]

45, this ammo was loaded twenty years ago. Keep in mind that a process like reloading is mechanical. It has nothing to do with finding your keys or your cell phone. There is no connection between the two things.

I think I've pretty certainly determined, at least for myself, that this was not at all related to a reloading issue. A pop out like that isn't what happens from pressure, there are many, many examples of a pressure failure, and this one isn't even remotely similar.

Of course I put my protection on after being reminded, and I was covered when the pop happened.

James, the balloon head was in use a lot longer than a person would expect. There were people who loved the old balloon heads, because every round that was fired swagger the primer pocket a little tighter. No loose primer pockets, and extra powder space.

No, I don't agree. This is the way it was. This is an explanation for the lack of .45 colt rifles, when the world was flooded with .45 large format, and dozens of .44 rounds. The .45 colt was treated like a black powder round long after it went smokeless.

 

[Jim Watson]

this ammo was loaded twenty years ago.

Now there's an interesting little tidbit.
Most of us think ammo ought to be stable for 20 years, but our buddy Slamfire says maybe not.

AA#2 is a dense powder. An overload would be easy.
Weak brass is not unknown, although less often in 9mm than .40.
Bullet setback against the feed ramp will raise pressures.
Lead fouling in a Glock leade is a known source of trouble.

I don't think you will be able to pin down the exact cause with so little evidence, certainly not on the internet.

By the way, if you want to pull a light bullet, don't whack your inertia puller on a piece of wood on top of a bench. A concrete floor is much more effective. If I can't knock out a bullet with a few licks on the end grain of a bench brace, I step out of the shop and beat it on the garage floor.

 

[briandg]

Actually, aa 2 is one of the least dense powders. A double charge is very evident, even a one or three grain over charge is pretty evident. This is why I chose it over nearly every other powder, along with burn rate.

Aa2 is. 11.6 gr/cc,, while .231 is lower density at 10.8, and many of the slower powders go into the range of 15. I believe that high speed powders, designed for small charges, should be as bulky as possible.

Is it interesting to anyone that two of the cases are berdan primers?

There it goes again, it is not aa nine, it is as two. Edited.

 

[James K]

I know of no US makers who were using balloon head cases 20 years ago or even 60 years ago. That is why I was surprised to see them in recent foreign ammo. With the cost of copper, the reason is purely economical; the savings in brass per case may seem tiny, but when you are making, say, 50 million rounds, it can add up.

The primary reason for lack of .45 Colt rifles in the old days was that the tiny rim presented too many extraction problems. Colt made it that way for the SAA so they could get by with only a small increase in cylinder diameter from the 1860 and could use much of the existing Model 1851/60/61 tooling. Of course, rim diameter mattered little in the SAA, with its rod ejector, but in a rifle, it made a lot of difference.

Jim

 

[briandg]

I 've heard th a about the rim, and also just general warnings about it being an inferior case to use in anything but the revolver cylinder.

As far as I know, yes that design was discontinued decades ago, but stock floated around forever. Somewhere, someone has these things squirreled away in a back room at an old sporting goods store, or so garage.

I remember reading a letter to one of the magazine's, a guy found ammo somewhere, and wondered what was wrong with his brass.

Anything in particular that allowed the colt to be useful now?

 

[Jim Watson]

Anything in particular that allowed the colt to be useful now?

Solid head cases with larger crisply turned rims. The little relief groove probably helps with a rifle extractor, too.

 

[briandg]

You're right. That groove was completely unnecessary when used onlyon revolvers, and it adds a few thousandth inches that a thin extractor can reach into. Grooving a rimmed pistol case seems unnecessary, but yes, once you start looking at it as a mechanical ejection rim, it's a different matter. Even rimmed rifle rounds are sometimes grooved, or otherwise as. It might be...

 

[briandg]

Here are links to photos of the cases. Seven in two groups, and I hope that you can get to them.
http://www.snapfish.com/library/sha...GE2ZaNJS5KWdDABKg/AUS/27939193723070/SNAPFISH
http://www.snapfish.com/library/sha...GE2ZaNJS5KWdDABKg/AUS/27939194321070/SNAPFISH

 

[James K]

I am astonished that a blowout like that did not result in more damage to the gun. The case seems to me to be too thin at that point, though. Any chance of sectioning one and seeing what it looks like?

On the .45 Colt in rifles, Jim Watson is right on both counts - more squared off rims and that groove, which is used in manufacturing the ammo in modern machines. And, of course, lever action rifles are not often used today for serious purposes, so an occasional failure won't result in anyone being harmed.

Jim

 

[TMD]

I can be pretty certain that it was once fired brass because it was purchased as once fired in a bucket

More often then not once fired brass is brass that someone picked up off a range and there is no telling how many times its been reloaded in the past.

 

[briandg]

That is exactly what I have been trying to say all along, nothing about it made any sense. They shot felt no different from another, sounded right, no abnormal signs at all just this thing. Every other blowout I have ever seen has been an explosive blowout of a section, and this was obviously a complex thing. It looks to me as if the tube began to expand, a separation formed at the rim,over at eight, a vertical split at eight formed. The brass just peeled off lo like that all the way across, like an old sardine can. It would have kept on going, but there is a notch where it ends at nine O clock, because the extractor caught it.

I sectioned a shell that should be identical, it's in the second set. Where this thing came off, that metal was thick. And again, the tear started up where the chamber was fully supported.

It always comes back to the question of if the brass was going to fail, wouldn't it have happened at the thin part, up in the chamber cut out, instead of in a supported section o n, and then running along the bead? If you could actually see this in person, it would leave you scratching your head.

Im pretty certain that it was only run a few times, maybe this was the second or third. It certainly shows no signs of hard use.

I just can't help thinking that there was some weakness that formed as the brass was drawn, and as the expansion cycled, it started to peel away.

 

[briandg]

It appeared to be once fired commercial when I bought the brass that went into this ammo. Looking over it. It still looks like new.

There are the pictures, and I've explained all that I can explain.

 

[James K]

Maybe I missed it, but what is the make of that case? I can't tell from the pictures.

Jim

 

[briandg]

Ordinary federal.