Ka BOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOM, Read & Weep

[35remington]

You do know more now than you did before, do you not? All these things are relevant to the discussion, and if they are not known, different viewpoints are plausible. Once they are known, certain hypothesis are clearly impossible.

How is it hard to believe that more information does not give you a better grasp of the probability of a given action happening, especially when due consideration is given to the forces involved? A barrel does not come out of battery if it is in battery to begin with until the bullet leaves and the pressure to cause a blowup is gone. A better understanding of what "in battery" means in terms of the forces involved was needed.

I gotta go to bed.

Let me offer a challenge: Next time you see/hear/read of an event like this happening, take a really close look at the case. Or ask the interested parties to do so, reinserting the case into the chamber if it is possible to do so.

Dollars to doughnuts you'll find the case goes all the way in, and the blowout is over the unsupported part of the chamber.

Whistle me up when you see anything different when the gun was claimed to be fired with a pull of the trigger. I won't hold my breath until that happens because it won't.

[303Guy]

I'm with 35remington. I don't have and never have had a Glock (I did hold one once and didn't really like the 'feel' and definitely didn't like the look - it's not exactly beautiful). In fact, I don't have any handguns at all, but I did have some once. So I'm no expert but I do have more than a basic understanding of the mechanics of things. Now a broken part might make a pistol fire out of battery (I don't really see how though). I know of at least one 1911 that AD'ed when the 'worked' safety was disengaged after pulling the trigger (some dumb *** turned the safety into a virtual trigger 'for speed of operation' in a fast draw. Safeties must draw the hammer back off the seer).

The way I see it. There may be one or two very rare 'firing out of battery' events all told but Glock blow-ups seem to be way too common to attribute the blow-ups to firing out of battery.

[mdi]

It's interesting to me how some people will hear something that sounds right to them, take it as gospel truth, and defend it with religious fervor if challenged. I've seen it multiple times when it comes to the "never shoot lead in a Glock" thing.

Some people get borderline violent about it. In a casual discussion about pistols I once told a guy that if you do it right (diameter, hardness, lube, cleaning, etc) it was perfectly safe to shoot lead in Glock barrels. The key of course is know what you're doing and do it right.

You would think I had told him that the earth is flat and his mother was a pig! He got downright condescending and insulting as he started lecturing me that "everyone" knows how dangerous that is, the almighty, all-knowing Gaston Glock says don't, and I must be borderline retarded to even think about it. Nowadays I'm a little sensitive on the subject so I try to just bite my tongue when people put their ignorance on display.

A few years ago I was given a bandoleer of old 30-06 AP rounds for my M1. I was talking to an acquaintance about guns and mentioned the ammo. He told me with an air of authority that I should NOT shoot it in any rifle that I wanted to stay accurate.

He had been told sometime in the past that steel-core ammo will strip out your rifling and ruin your rifle within a few shots.

I didn't know the guy very well, and I'm too nice to just tell him that was the biggest bunch of absolute BS I'd heard in my life, so I just smiled and thanked him for the warning. I try to do that about the Glock thing now too.

There are some people out there that, for some psychological reason, must be an "expert". They may know a little on the subject, but something in their little pea brains tells them they are absolutely, positively correct, and everyone else is an idiot. "Manly/Macho" things are where this situation is most often seen (sports, guns, hunting, cars, etc.). Sometimes I can get caught up in the "discussion" and try to tell the "expert" he's full of beans, but it's like wrestling with a pig, you get all muddy and the pig loves it. I know I don't know everything, and I am always willing to learn, but I much prefer reliable sources...

BTW, I shot a box of ammo through a Glock a few years ago (45 ACP). Wasn't impressed either way...

[W.R.Buchanan]

OK I will insert my .02 here again. First,,,35 Rem's description of what is happening with a Glocks firing cycle is exactly right.

Another point to add to his blurb is that once the barrel hood goes below the slide the firing pin safety is no longer engaged. The little ramp on the trigger bar does this and it only reaches the safety plunger when the slide is closed, or nearly so,,, as the slide opens the ramp releases the plunger. As soon as the point of the ramp is off the plungers top surface the plunger blocks the firing pin and the gun can't fire.

If you want to see a Glock not go into complete battery or more properly sticky battery just wash all of the lubricant out of the gun and try it. Usually the slide will only go all the way home when pulled all the way back and released, and even then it is iffy. I have experienced this first hand and the simple cure for the day was a shot of WD40 on the slide ways . Now the gun is dosed with Frog Lube and these problems don't arise.

Another point here referring to the OP's original topic is that these types of failures usually occur on the first shot when the slide is racked and not allowed to function normally. IE the shooter doesn't release the slide from the rearmost position. Like in watching the gun strip a round while chambering to chamber check. I do this and it is a bad habit I need to break. There is a loaded chamber indicator on the extractor that will tell you if anything is in the hole.

When I had MY ND this is what caused it. I released the slide from about half way closed and then pushed on the back of the slide with my thumb while my finger slipped into the trigger guard and fired the gun into the ground. This was entirely my fault and the gun was in fact in battery when it occurred, the extra action of pushing the slide down is what caused the ND. Changes have been made to prevent this from happening again.

The pictures of the cartridge that was blown out that I posted earlier in this thread were NOT caused by and out of battery condition. It was caused by a poorly designed case with insufficient web height to reinforce the unsupported area of the case during firing.

Now all .40 S&W cases have a much higher web and that has pretty much cured that problem. However idiots loading cases that have been fired many times, not debulged or just plain bad, with hot loads still can experience KABOOM.

Somebody earlier mentioned "Stacking Tolerances." With out sounding too harsh, there is not too much Stacking of Tolerances that can take place in gun building.

Stacking of Tolerances refers to the thing that happens on a machined part when dimensions with different datum's are allowed to proliferate.

Simply put one hole is located from the end of the part and the subsequent holes in a line are all located based on the previous holes locations. if the tolerance is say +/-.010 and the moves are all on the plus side of the tolerance, then by the time you've gotten to the fifth or sixth hole you can be as much as .05-.06 off in your hole position. However per the drawing you are still good to go. This is usually caused by an incompetent engineer incorrectly dimensioning the drawing.


However If you have ever actually seen a drawing for a gun part (I actually have the drawings for the M14 receiver which are 7 pages long) EVERY SINGLE DIMENSION has it's own tolerance and it's own datum, SPECIFICALLY so that tolerance stacking cannot occur.

When I dimension a drawing typically I call out all dimensions from one edge of the part for both axis'. That way the farthest any given feature can vary is the actual "drawing tolerance" which in my case is generally +/- .005. This way stacked tolerances cannot occur. Every feature stands by itself and is not contingent on any other feature.

All competent engineers and machinists do this normally. I'm sure Glock does too.

Randy

[KYCaster]

OK, I obviously didn't understand the meanings of the terms "out of battery" and "tolerance stacking". Now that I've been educated in the semantics of the discussion, I'll rephrase my statement so it may make sense to everyone.

Because of the generous tolerances Glock uses in the manufacture of their guns, a situation can occur where the unsupported area of the chamber falls forward of the point where the cartridge brass is capable of containing the pressure.

The result is the "classic Glock kaboom", resulting in pressure vented into the mag well, usually causing damage to the frame, extracter, trigger mechanism and magazine, but normally not causing any serious injury to the shooter; not to be confused with a catastrophic failure of the chamber/barrel/slide caused by excessive pressure.

Does that make more sense?

Jerry

[35remington]

Yep, KY.

I understand, however, that the way Glock make chambers now is different (to what extent I do not know for sure as I have not made chamber casts of dozens of early and late model Glocks) and some levels of kB's are.......supposedly.........caused by overworked and overflexed brass that has been reloaded and reused when it should not be. The unsupported chamber warning was/is very common in the handloading literature. I do not know to what extent it was the actual problem and to what extent it was overactive imagination.

My presumption is the great hulabaloo over lack of case support was to ensure that the usual amount of "hot rodding" did not take place wherein guys figure the loading recommendations are conservative and "bump the load up" to give everything a little more pep. The warnings seemed to be intended to get the idea across that the more accustomed to levels of safety redundancy were not present with such chambers/barrels.

Throw in pickup range brass with uncertain heritage and you've supposedly got problems. Supposedly. I cannot resolve that issue here in any way.....I'm just addressing the chance the pistol will fire out of battery with a pull of the trigger, which is zero. I know expressing it that way will irritate some people, but it's relatively easy to engineer a part to ensure that something will never happen, especially when the possibility of parts failure is irrelevant in ensuring that said event never happens. As mentioned, every part on the gun can fail and it still won't fire out of battery.

[Shiloh]

Also he said the gun had not been cleaned for about 2000 rds.


Who shoots 2000 rounds of cast lead boolits without cleaning??

At what point between round #1 and round #2000 did the accuracy completely fall off from the leading??

My guns develop functioning problems with a LOT fewer rounds than that. They are filthy from the lube or ALOX residue combined with powder residue. Never had issues with lead boolits in a 9mm Glock. The .40 was a different story. KaBoomed two before I went with an afermarket barrel.

Shiloh

[MBTcustom]

Shiloh STOP.

You are making way too much sense.

[dubber123]

Also he said the gun had not been cleaned for about 2000 rds.


Who shoots 2000 rounds of cast lead boolits without cleaning??

At what point between round #1 and round #2000 did the accuracy completely fall off from the leading??

My guns develop functioning problems with a LOT fewer rounds than that. They are filthy from the lube or ALOX residue combined with powder residue. Never had issues with lead boolits in a 9mm Glock. The .40 was a different story. KaBoomed two before I went with an afermarket barrel.

Shiloh

I tried it once. I read an article where Ross Seyfried claimed to only clean his 1911's every 10,000 rounds, just adding enough oil to "keep the gunk fluid" I believe was how he put it. My Springfield made it to 7,000+ rounds without a failure, LEE 228 RN with my lube, and either Bullseye or Green Dot powder to produce 850 fps. When it failed, it was a failure to chamber due to lead buildup in the chamber. I scraped it out quickly and it went almost another 4,000 rounds before it did it again. It was more of a stunt than anything, but it proved a lot to the shooters at the club about lead boolits and leading. I have since fully cleaned it, with the exception of the bore, which is still clean and shiny. The best way to cure leading is don't let it start in the first place.

[10x]

I may be wrong but I don't think that damage to that gun is due to shooting led bullets, seems to me there is an error some place else that nobody wants to admit. I would think (well it don't matter what I think ) just glad nobody got hurt. I mean if it blew the case apart where it was unsupported maybe a case failure, really hot round I don't know. But if you shoot long enough things like this may happen just like driving in a car you never know when you are going to get in a crash.

This is a pressure event causing a parts failure.
It is possibly a design fault of the gun maybe?
The gun looks as if it were fired with a very high pressure round before the cartridge was completely seated in the chamber.
I suspect operator error in reloading rather than a problem with cast bullets...

[303Guy]

Have a look here.

http://www.google.co.nz/search?q=Ima...w=1680&bih=891

Plenty blown Glocks and unsupported cases!

http://img403.imageshack.us/img403/5...swchambers.jpg

[303Guy]

I read that the reason for the unsupported case design is reliability. Well, I had a Star DKL in 380 ACP which would feed empty cases from the mag with either slow cycling of the slide of dropping it forward. It never once hung on me (not that I fired it that much). But it had a fully supporting chamber.

[W.R.Buchanan]

303guy: your pics are excellent and tell the story very well. The only change I would make to the drawing of the cartridge is that the web of the cases is actually has a radius in the corners instead of being square. and that web radius is what is preventing the cartridge case from failing.

The picture of the early G23 barrel versus the later ones is a good example of the changes Glock has made over the years to minimize the unsupported area of the case..

I find that the Cases are usually at fault before gun problems. That .45 acp case appeared to be an overload. However it was a factory load (notice the red primer seal) Maybe a +p loading, Notice the flat primer which doesn't occur in normally loaded .45's as there isn't enough pressure to do it. Another give away is that the vast majority of KB's are with .40 S&W's versions and not .45's. first one of those I have seen pics of. But after looking closer the web between the chamber and the unlocking lug below the barrel is awfully thin. My gun's chamber is a lot heavier there.

One thing that must be emphasized here is that this problem of unsupported chambers is not only with Glocks. First Glock chambers are not any bigger and in some case smaller than other guns. I had a Para 16-40 LDA .40 S&W, the gun was a 1911 style gun and the chamber was about .004 bigger(.438) in dia. than my Glocks chamber and unsupported area was about 20% larger. I also have a Storm Lake barrel for my G35 and the only difference between it and the stock one is the type of rifling and the chamber is about .428 in dia. versus .434 for the stock barrel. The unsupported area is about the same size. I might add that this barrel isn't even remotely reliable, thus it doesn't get used.

As a point of dimensions; an unfired .40 S&W case measures about .421-422 in dia. before it is fired. If fired in a chamber that is .434 it will expand to .434 and then shrink down to around .433-2. This amounts to about .005-.007 expansion per side on the case. That is not very much but it is visible as a bulge . By not removing the bulge the case is already to it's limit and there is no cushioning effect, so the likelyhood of failure is higher especially if the case happens to index into the same position in the chamber as it had previously been fired in. Then a combination of the already weakened area and no expansion to cushion the pressure spike can result in a blow out. Obviously the weaker the case head the more likely the event is to happen.

The FC and FC-10 cases I mentioned earlier were responsible for many blow ups including the gun that fired the one I found at the range. I didn't fire that round luckily but I found about 10 more of those cases in the batch I picked up at the range that day. I don't believe that case was fired in a Glock Pistol either since it has a round striker make on the primer and Glocks have a rectangle one. Also the Santa Barbara CA Police Dept. is not allowed to carry Glocks, they carry Sig's.

About the only way you are going to get a completely supported chamber in a .40 S&W gun is to buy a S&W 610 which is a Revolver.

Was the nickel case a reload? cuz it was very close to blowing and that bulge was not caused by a bad barrel.

On another note: I just played with my G21 and the gun will not fire until the barrel is going up into battery and is at least half way up into the cutout in the slide. IN other terms if the slide has moved to the rear .100 or 2.5 mm the gun will not fire and you can feel when the trigger disconnects from the striker. If it is further closed then it will fire however the gun is still in battery meaning the locking block is at least half way up into the locking cutout in the slide. The barrel only drops .075-.080 between fully closed(in battery) and completely out of battery. Once the barrel has dropped .040 (about half way) the slide has moved .100+ and the trigger is no longer in contact with the striker. Also the firing pin safety is no longer depressed meaning the striker can not travel past the slide face.

It appears that this gun could not fire unless the slide is at least half way closed during the last half of phase of the cycle where the barrel is going into battery in the slide and the slide is within .100 of it's final position fore and aft. IN any event, the bolt face or slide face is still in its proper position for firing in relation to the chamber. IE closing the back of the chamber. Also in this case the firing pin safety is no longer depressed either as the trigger bar is in front of it.

This gun will only fire if the slide is nearly all the way home and I'm talking less than .020 back will stop it from going off. this action is prevented by either the trigger disconnecting or the firing pin safety.

I'd need three to four hands to take pics of all these different positions so you will have to read and reread the post to understand all the content. It's all there.

Randy

[Harter66]

The XD seems pretty well supported in 40.
Attachment 90632

[W.R.Buchanan]

Harter: The unsupported area where the feed ramp intersects the chamber is about the same size as the G23 pics above.

Here's another little tidbit guys. Most all of these guns have this same relationship and there are very few exceptions simply because it has to be like this in order to function reliably.

It ain't that big a deal. REALLY!

What really drives me nuts about this whole conversation is that even though Glock Pistols are used by more Agencies in the world than all other pistol types combined, they still suffer from this "stigma," which was perpetrated by some gun writer early on and as been amplified to ridiculous proportions.

If you look at the percentage% of failures with these guns you will probably see a lower percentage rate of failure than virtually every other auto pistol out there. The reason they are so maligned is because there are so many of them. Just like VW bugs were maligned in the past. Some people loved them and some hated them. However we didn't have the internet back then to spread the BS about how unsafe they really were, we relied on the evening news instead. The News hasn't changed in that regard, but it has been amplified greatly by the internet, and the speed which news travels now is much faster, so BS can travel just as fast.

Randy

[boatworks]

I had a S&W model 99, .40 cal kabooom on me......handloaded range brass with a bulge, the round didn't actually chamber but the firing pin hit it anyway. Blew the frame apart, S&W replaced it anyway. Great company.

[dnotarianni]

Every time I read about a Glock grenade I remember the article where Glock mentioned it only cost them $75 to build a gun. Everything else was markup and profit.

[jmort]

Love seeing the Glock fan-boys get wound-up.

[MtGun44]

KUDOS TO 303 Guy!!!!

Great pix. Well done. Folks don't believe there is an "unsupported area" until you prove it.

I have them put a case in the dismounted barrel and spray a short shot of paint at the case/feed ramp
area then pull the case. They are surprised at where the steel isn't.

Like I said - Over pressure, some ammo issue, VERY high probability of double charge.

People just want to believe in the "gun malfunction fairy" rather than they made bad ammo.

That said - I have seen a letter sent by the head of the Federal Police (yes they exist in the USA) to Glock
asking why so many Glock 40s were blowing up WITH FACTORY AMMO! Never saw an answer, but
apparently Glock has changed the guns.

NEVER EVER heard of even ONE case of a 9mm or .40 or .45 cal 1911 blown up with FACTORY AMMO.
Handloads - yes. Factory - nope. 35 years of competition with pistols and never even heard a third hand
story. I have seen and even done it myself with handloads. Never heard of a single case of a Glock 9mm
blown up. . . . . . LOTS of .40s, tho.

Bill

[mpmarty]

Had a Glock 21 in or about 1983 and used it in IPSC. Many thousands of rounds all cast no problems. Sold it and got a 23 in 40 Short & Weak and hated that pistol with a passion. Sold it and No more GLOCKS for me. I much prefer 1911s and Tanfoglio Witnesses in all steel.