I blew up my Glock .40 with reloads - Help me figure out what I did wrong - UPDATE PG 4 - PLUS PICS - Page 3

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[ARCHIVED THREAD] - I blew up my Glock .40 with reloads - Help me figure out what I did wrong - UPDATE PG 4 - PLUS PICS (Page 3 of 4)

Posted: 10/28/2009 6:19:05 AM EDT

[#1]

Quoted:

Quoted:
I'm still thinking setback

http://i101.photobucket.com/albums/m54/nfe6848m/Maybe_Setback.jpg

Wow, I didn't see that line till now. In fact, it's still very hard to see it with the naked eye. The flash of the camera sure highlights it though. Well damn, that changes my thinking. If that line is where the tail of the bullet was when fired then that is definately a set back. Just by eyeballing it, if that were it, the COAL for the KB was around 1.05". Thats far short of the 1.125" called for in the manuals.

So just so I understand what you guys are thinking, let me restate for clarification. The bullet got pushed in while chambering, that caused the brass to bulge a little bit, causing the round to not fully chamber, thus also causing a slightly OOB firing, and an overpressurization issue due to the set back?

What do you think about that raised lip in the picture? Is that OOB? Or can the brass push that far out during a KB?

Take some pictures of some of the fired brass primers and the kaboom brass primer.

If they are all center hits it didn't fire out of battery..

If they are all high hits then you didn't finished installing your aftermarket barrel.

Or, the COAL was too long and the didn't go in all the way. <–– Lone Wolf barrels specialize in this.

Posted: 10/28/2009 7:02:43 AM EDT

[#2]

Quoted:

Quoted:
Wow, I didn't see that line till now. In fact, it's still very hard to see it with the naked eye. The flash of the camera sure highlights it though. Well damn, that changes my thinking. If that line is where the tail of the bullet was when fired then that is definately a set back. Just by eyeballing it, if that were it, the COAL for the KB was around 1.05". Thats far short of the 1.125" called for in the manuals.

So just so I understand what you guys are thinking, let me restate for clarification. The bullet got pushed in while chambering, that caused the brass to bulge a little bit, causing the round to not fully chamber, thus also causing a slightly OOB firing, and an overpressurization issue due to the set back?

What do you think about that raised lip in the picture? Is that OOB? Or can the brass push that far out during a KB?

Take some pictures of some of the fired brass primers and the kaboom brass primer.

If they are all center hits it didn't fire out of battery..

If they are all high hits then you didn't finished installing your aftermarket barrel.

Or, the COAL was too long and the didn't go in all the way. <–– Lone Wolf barrels specialize in this.

The primer blew out, and I don't have an aftermarket barrel.

Posted: 10/28/2009 7:23:22 AM EDT

[#3]

Quoted:

Quoted:
Wow, I didn't see that line till now. In fact, it's still very hard to see it with the naked eye. The flash of the camera sure highlights it though. Well damn, that changes my thinking. If that line is where the tail of the bullet was when fired then that is definately a set back. Just by eyeballing it, if that were it, the COAL for the KB was around 1.05". Thats far short of the 1.125" called for in the manuals.

So just so I understand what you guys are thinking, let me restate for clarification. The bullet got pushed in while chambering, that caused the brass to bulge a little bit, causing the round to not fully chamber, thus also causing a slightly OOB firing, and an overpressurization issue due to the set back?

What do you think about that raised lip in the picture? Is that OOB? Or can the brass push that far out during a KB?

Take some pictures of some of the fired brass primers and the kaboom brass primer.

If they are all center hits it didn't fire out of battery..

If they are all high hits then you didn't finished installing your aftermarket barrel.

Or, the COAL was too long and the didn't go in all the way. <–– Lone Wolf barrels specialize in this.

The primer blew out, and I don't have an aftermarket barrel.

Sorry, I saw the K and immediatly thought KKM.

Posted: 10/28/2009 8:21:03 AM EDT

[#4]

Excellent information in this thread.

I have a refurb Glock 22 that I shoot. I run a KKM .357Sig barrel in it with purely reloads and it has fed 100%. I use Berrys 124gr plated flat points with the WSP and max loads of Unique with as heavy crimp that I can get.

I have only fired factory loads in it with the factory .40 barrel with very limited quantities.

To the poster that says the .45ACP Glock has the highest rate of KBs, I would really like to see some real data on that. We have been shooting several of them in the family with purely reloads (mainly lead) for tens of thousands of rounds with no signs of any over pressure/bulge problem. The .45 isn't known for being a high pressure load, so I really have to fly the

flag on this.

Posted: 10/28/2009 9:37:39 AM EDT

[#5]

Quoted:

Quoted:
I'm still thinking setback

http://i101.photobucket.com/albums/m54/nfe6848m/Maybe_Setback.jpg

Wow, I didn't see that line till now. In fact, it's still very hard to see it with the naked eye. The flash of the camera sure highlights it though. Well damn, that changes my thinking. If that line is where the tail of the bullet was when fired then that is definately a set back. Just by eyeballing it, if that were it, the COAL for the KB was around 1.05". Thats far short of the 1.125" called for in the manuals.

So just so I understand what you guys are thinking, let me restate for clarification. The bullet got pushed in while chambering, that caused the brass to bulge a little bit, causing the round to not fully chamber, thus also causing a slightly OOB firing, and an overpressurization issue due to the set back?

What do you think about that raised lip in the picture? Is that OOB? Or can the brass push that far out during a KB?

If the round went off while fully seated and locked, only the part of the round unsupported would expand. If it was seated and locked in battery it wouldn't have lost its primer either. As far the bullet line is concerned, that could very well be another additional factor in this. I know it's not much consolation, but at least you had all your bad luck at one time and have case evidence of all the things that can go wrong to learn from. Of course you will or already have checked your un-shot, seated rounds for comparison. The gun's normal recoil can move bullets, in brass with insufficient tension, waiting in the magazine to be fired. But that was your first shot, so it had to move while chambering. It's well known in police circles that a bullet that is chambered and rechambered several times during the process of unloading and reloading the firearm, can and does move in the case even with decent tension. The instructions to officers is usually to rotate which bullet is on top and chambered each time.

It looks as if Glock is making this all hurt less by fixing your gun very reasonably. PR-wise that's absolutely the only wise thing for them to do. The PR from this thread is bad enough. It would be worse with a bad experience with the company. Anyway, I'm glad they are taking care of you. If the company was Ruger, they would investigate, find the problem, publicly recall all the guns and retro fix everything sold. They've done that once already for two of their recent releases. That makes me unafraid to buy anything Ruger. Glock's record is less stellar with their "perfect" gun. Fixes are done quietly. I've seen some of the newest Glocks, and compared with the older ones, the case support has improved a little.

Federal "improved" their .40S&W cases and beefed them up at the web area. Looks to me like Remington needs to also.

Posted: 10/28/2009 9:45:14 AM EDT

[#6]

Quoted:
I took all the remaining rounds and did the following test. (I don’t have a bathroom scale so I can’t do the push test to check) I measured the COAL, put it into my G23 magazine and racked the slide. I did it three times per bullet. I then measured COAL again. The max reduction in COAL was from 1.130” down to 1.129” after three chamberings. This is still in the acceptable range. Even if there was some setback on the single time the KB round was chambered, I don’t think it was enough to cause a KB. But, I am brand new to this stuff, so I could definitely be wrong.

No, you did that test EXACTLY RIGHT! I have been preaching that exact test for years. You are a new reloader & you got it right the first time.

The manuals that preach "push it against uh bench" should be shredded. That test tells you nothing. In contrast, the test you did comes closer to the conditions the round will experience in actual firing. Plus you measured the change in OAL. Well done!

I agree with the others though - it was probably set back caused by a bad piece of brass.

Why?

1) Double charges in a .40 usually split the barrel. Your event involved high pressure - but not THAT high.

2) Early 40 brass was notorious for case head separations. Usually the head blows clean off the case. Your KB was not that bad.

3) There is BAD brass out there. How would I know? I worked at an indoor range that sold "commercial reloads." We sold all our brass right back to the same commercial reloader. Back it came to us. Over and over again. Some of that brass could have had DOZENS of loadings on it. Such a piece of brass could contribute to set back.

How old are your magazine springs? Weak springs can cause the rounds to slam into the feed ramp at a lower point - causing set back.

Posted: 10/28/2009 11:35:57 AM EDT

[#7]

[[/quote]

How old are your magazine springs? Weak springs can cause the rounds to slam into the feed ramp at a lower point - causing set back.
[/quote]

Forgive me, but can use please explain this? I dont understand how a mag spring would affect set back. My though would be that the recoil spring would be responsible for seating the bullet as long as the mag spring got it in the right place for the slide to pick up.
Great info in this thread and lots to think about.

Posted: 10/28/2009 12:48:28 PM EDT

[#8]

Quoted:
My intention isn't to flame anybody...I happen to like Glocks just fine. But when I buy my own Glock, I WILL get a supported barrel and it will be in .45. (.45 Glocks with the original barrel go kaboom more often than other brands too...and the LE agenies don't use many .45's, so the ratio argument doesn't hold.)

Is there any supporting evidence for this? I've run searches of AR15.com and also Google'd and have yet to find a single reliable report of a .45ACP Glock KB. I see veiled references to them (such as yours), but no actual detail whatsoever. Maybe my search fu is weak, but I'd really like to see any actual data on this.
I reload for my Glock 21, but I've only shot about 70 rounds of reloads in it so far, I have 200 sitting on a table waiting for the range. Quite frankly, all the talk of unsupported barrels freaks me out so I ordered a LW barrel yesterday, I figure if nothing else, I'll be able to save money by shooting lead.
That said, I'll keep my factory barrel in it for CCW and have always carried commercial ammo for CCW anyway. My understanding (again, based only on posts from Arfcom, so beware) is that .45ACP is lower pressure and much less risky than 9mm Glocks. In addition, I think the statistical factor of how many Glocks are out there vs. other pistols makes a good case that it's probably not as risky as the reports would have us believe.
But all that is just my notably uninformed opinion. Would be nice to have some actual facts (rather than anecdotes) to back it up or disprove it.
ETA: Again, not much in the way of specific events, this may be a reasonable source? http://www.thegunzone.com/glock/glock-kb-faq.html

ETA2:

OK, so it seems there are actually a lot of reports if your search fu is better than mine was at first. I won't post them all here, but I did find a news article about Portland Police (right next door to me!) recalling all G21's due to 2 KB's that happened during training. In the end, I'm sticking with mine. And I think the statistical argument is helped a bit by this:

"More than 7,500 law enforcement agencies, or about 65 percent of the market, use Glocks, according to the company's Web site."

Here's the article, from 2004: http://www.realpolice.net/forums/firearms-4/10770-portland-police-suspend-use-glock-45-cal.html

I'll continue reloading - with care - for my G21... Note that one article stated the primary reason noted for failures is that Glocks will fire OOB easier than other guns.

In other words, use a case gauge, resize your brass correctly, and use an aftermarket barrel.

Posted: 10/28/2009 12:58:43 PM EDT

[#9]

Extremely weak mag springs are known to cause "nose dive" jams where the bullet is jammed into the foot of the ramp. Replacing the spring usually cures this. Stands to reason that weakend springs do not push the round up enough to feed smoothly into the chamber. Hence, they crash into the ramp too low & can possibly set back.

Quoted:
[

How old are your magazine springs? Weak springs can cause the rounds to slam into the feed ramp at a lower point - causing set back.
[/quote]

Forgive me, but can use please explain this? I dont understand how a mag spring would affect set back. My though would be that the recoil spring would be responsible for seating the bullet as long as the mag spring got it in the right place for the slide to pick up.
Great info in this thread and lots to think about.[/quote]

Posted: 10/28/2009 2:03:47 PM EDT

[#10]

A squib round in the barrel would explain:
1) evidence of high pressure
2) possible out of battery firing
3) possible bullet set-back

I'm still thinking that unless the OP is 100% positive that the round prior to the KB exited the barrel, a squib is a strong possibility.

Posted: 10/28/2009 2:11:55 PM EDT

[#11]

Also, the force vs. pressure thing is getting over used as well. How much uniique or power pistol powder in a 9mm vs. a .45ACP? More powder means bigger KaBoom.

I would hope the Arfcom KaBoom forensics team would determine the cause for the OPs glock rapid disassembly.

The op made an interesting observation in his last batch of photos. He thinks it fired about 1/32 to 1/16" OOB. Does anyone agree? Are all autopistols capable of firing OOB or easy to fire OOB? 1911, Beretta 92, 96, Glock, ParaORD, PPK, S&W, H&K, etc.

Posted: 10/28/2009 2:23:33 PM EDT

[#12]

TO OP
Did this occur during rapid fire or slow deliberate fire?

Posted: 10/28/2009 2:27:55 PM EDT

[#13]

Quoted:
Every person that has an aftermarket barrel in their Glock pistol and has reliability problems please chime in.

If you removed an aftermarket barrel due to poor reliability and reinstalled the factory barrel, tell us that, too.

The issue with the unsupported chamber in Glock pistols is not the fact, it's the degree. Anyone can simply look at the barrel with a cartridge in the chamber and clearly see without taking a measurement that the unsupported length of the case is extreme.

I recently purchased a lone wolf for my G21.....I have deffinently noticed the reliabilty has gone WAY down...this thing likes lead bullets set DEEP, I suspect the chamber is much tighter and the lead of the throat much shorter. Once I have adjusted my ammo according to what the barrel likes I have had much less failures to feed, however it just isnt nearly as reliable, but if I'm sacrificing reliability at the range, where the targets dont shoot back, for durability (This is my duty weapon after all) I'll take that trade off.

I have heard if you send yer barrel back to lone wolf with some sample dummy rounds they will cut the throat/chamber to work for yer ammo...I may look into this, as I purchased the barrel for shooting reloads and lead not match accuracy.

Posted: 10/28/2009 3:24:51 PM EDT

[#14]

Quoted:
TO OP
Did this occur during rapid fire or slow deliberate fire?

Slow, deliberate fire. This was all going over a chronograph to a relatively fresh target each time. I wanted to shoot to clear targets as I was trying to test accuracy as well. I was also pausing between each shot to chart the FPS in my ,notebook.

As for the squib possibility. First, anything is possible. Second, I'm a new reloader, but I've been shooting glocks for 8 years. I did not see or hear anything unusual when I fired the last round of the previous magazine. The KB round was the first round in a magazine.

Posted: 10/28/2009 3:32:10 PM EDT

[#15]

Quoted:

SNIP

I reload for my Glock 21, but I've only shot about 70 rounds of reloads in it so far, I have 200 sitting on a table waiting for the range. Quite frankly, all the talk of unsupported barrels freaks me out so I ordered a LW barrel yesterday, I figure if nothing else, I'll be able to save money by shooting lead.

That said, I'll keep my factory barrel in it for CCW and have always carried commercial ammo for CCW anyway. My understanding (again, based only on posts from Arfcom, so beware) is that .45ACP is lower pressure and much less risky than 9mm Glocks. In addition, I think the statistical factor of how many Glocks are out there vs. other pistols makes a good case that it's probably not as risky as the reports would have us believe.

But all that is just my notably uninformed opinion. Would be nice to have some actual facts (rather than anecdotes) to back it up or disprove it.

SNIP

In other words, use a case gauge, resize your brass correctly, and use an aftermarket barrel.

[/div]

The stuff in red above is how I will do it if I decide to reload again for my glocks.

I want to be able to load for all calibers. I'm never going to put a reload in a factory glock barrel again. So for me it comes down to either getting an aftermarket barrel for my glocks, or selling them. I'm still trying to figure out how I feel about the fact that Glocks require special treatment for reloading.

Edited for spelling.

Posted: 10/28/2009 4:00:04 PM EDT

[#16]

Quoted:

Quoted:

SNIP

I reload for my Glock 21, but I've only shot about 70 rounds of reloads in it so far, I have 200 sitting on a table waiting for the range. Quite frankly, all the talk of unsupported barrels freaks me out so I ordered a LW barrel yesterday, I figure if nothing else, I'll be able to save money by shooting lead.

That said, I'll keep my factory barrel in it for CCW and have always carried commercial ammo for CCW anyway. My understanding (again, based only on posts from Arfcom, so beware) is that .45ACP is lower pressure and much less risky than 9mm Glocks. In addition, I think the statistical factor of how many Glocks are out there vs. other pistols makes a good case that it's probably not as risky as the reports would have us believe.

But all that is just my notably uninformed opinion. Would be nice to have some actual facts (rather than anecdotes) to back it up or disprove it.

SNIP

In other words, use a case gauge, resize your brass correctly, and use an aftermarket barrel.

[/div]

The stuff in read above is how I will do it if I decide to reload again for my glocks.

I want to be able to load for all calibers. I'm never going to put a reload in a factory glock barrel again. So for me it comes down to either getting an aftermarket barrel for my glocks, or selling them. I'm still trying to figure out how I feel about the fact that Glocks require special treatment for reloading.

You have to decide what you feel comfortable with. I have loaded and fired well over 150,000 rounds through Glocks, most of them through factory barrels. If you keep your loads moderate and use jacketed bullets, I truly believe you have nothing to worry about. I have installed Lone Wolf barrels in 2 of my pistols just because I want to shoot lead and polymer coated bullets. I shoot only jacketed in factory bullets although I know people who shoot everything in Glock factory barrels.

Posted: 10/28/2009 5:05:01 PM EDT

[#17]

Quoted:

Not trying to be a smartass here ,but whats the moral of the story here ? Buy a lone wolf or kkm barrel ? Glad to hear that the OP is ok...hang in there with reloading man...this has me perplexed as I have several Glocks, and have never had this problem with my loads.

This.

Glock factory barrels are for new factory loaded ammo. Get an aftermarket barrel for reloads.

Posted: 10/28/2009 5:13:02 PM EDT

[#18]

Quoted:

Quoted:
SNIP
I reload for my Glock 21, but I've only shot about 70 rounds of reloads in it so far, I have 200 sitting on a table waiting for the range. Quite frankly, all the talk of unsupported barrels freaks me out so I ordered a LW barrel yesterday, I figure if nothing else, I'll be able to save money by shooting lead.
That said, I'll keep my factory barrel in it for CCW and have always carried commercial ammo for CCW anyway. My understanding (again, based only on posts from Arfcom, so beware) is that .45ACP is lower pressure and much less risky than 9mm Glocks. In addition, I think the statistical factor of how many Glocks are out there vs. other pistols makes a good case that it's probably not as risky as the reports would have us believe.
But all that is just my notably uninformed opinion. Would be nice to have some actual facts (rather than anecdotes) to back it up or disprove it.
SNIP
In other words, use a case gauge, resize your brass correctly, and use an aftermarket barrel.

[/div]
The stuff in red above is how I will do it if I decide to reload again for my glocks.
I want to be able to load for all calibers. I'm never going to put a reload in a factory glock barrel again. So for me it comes down to either getting an aftermarket barrel for my glocks, or selling them. I'm still trying to figure out how I feel about the fact that Glocks require special treatment for reloading.
Edited for spelling.

This is exactly what I do.

ETA: Glock specifically states in their user's manuals NOT to use reloads. The reason being they don't use fully supported chambers. Why don't Glock barrels have fully supported chambers? Because of reliability.

Posted: 10/28/2009 7:22:07 PM EDT

[#19]

Quoted:

ETA: Glock specifically states in their user's manuals NOT to use reloads. The reason being they don't use fully supported chambers. Why don't Glock barrels have fully supported chambers? Because of reliability.

This is the flaw of our over-litigious society. EVERYTHING has warning labels on it, so you no longer know what warnings are valid, and what warnings only apply to the dumbest of idiots. In this case, the Glock warning was legit - whereas the same warning that every single other gun manufacturer on the planet Earth is not. Kind of says something about this particular gun...

Posted: 10/28/2009 8:45:51 PM EDT

[#20]

Quoted:

Quoted:
TO OP
Did this occur during rapid fire or slow deliberate fire?

Slow, deliberate fire. This was all going over a chronograph to a relatively fresh target each time. I wanted to shoot to clear targets as I was trying to test accuracy as well. I was also pausing between each shot to chart the FPS in my ,notebook.

As for the squib possibility. First, anything is possible. Second, I'm a new reloader, but I've been shooting glocks for 8 years. I did not see or hear anything unusual when I fired the last round of the previous magazine. The KB round was the first round in a magazine.

My load workup sheet. See how the velocities just abruptly stop?

Explain the abrupt stop in your work up sheet , when did it occur ? was it the KB or before ?

Posted: 10/28/2009 11:34:26 PM EDT

[#21]

Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

Posted: 10/29/2009 1:17:01 AM EDT

[#22]

Quoted:

Quoted:
TO OP
Did this occur during rapid fire or slow deliberate fire?

Slow, deliberate fire. This was all going over a chronograph to a relatively fresh target each time. I wanted to shoot to clear targets as I was trying to test accuracy as well. I was also pausing between each shot to chart the FPS in my ,notebook.

As for the squib possibility. First, anything is possible. Second, I'm a new reloader, but I've been shooting glocks for 8 years. I did not see or hear anything unusual when I fired the last round of the previous magazine. The KB round was the first round in a magazine.

My load workup sheet. See how the velocities just abruptly stop?

Explain the abrupt stop in your work up sheet , when did it occur ? was it the KB or before ?

The last velocity charted is the one before the KB. The first blank velocity is the KB. I wasn't sure if my hands were OK or not and I wanted to bail out of there as fast as possible. I didn't look at the chrono before I unplugged it.

Posted: 10/29/2009 1:19:07 AM EDT

[#23]

Quoted:
Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

I'm laughing aloud right now. After the stuff I've read recently, you sure hit the nail on the head.

Posted: 10/29/2009 7:39:12 AM EDT

[#24]

Quoted:

Quoted:
Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

I'm laughing aloud right now. After the stuff I've read recently, you sure hit the nail on the head.

I've shot 1000's and 1000's of more than once fired brass out of my glocks. The speers book spells it out clearly. DO NOT GO NEAR MAX loads with a most auto pistols, especially the Glock. Berry bullets shoot just like lead cast bullets without any leading. RS states max load for 180gr lead @ 5.7 TB. You where 6.0. That's .3 grains over max in a glock. I'm guessing your pressure PSI was way past 35,000. Yes, the case failed but it also blew the primer out. That is a sure sign of way to much pressure.

To much powder. That's all. Nothing scientific on what happened.

Posted: 10/29/2009 12:15:41 PM EDT

[#25]

Quoted:

Quoted:
Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

I'm laughing aloud right now. After the stuff I've read recently, you sure hit the nail on the head.

I've shot 1000's and 1000's of more than once fired brass out of my glocks. The speers book spells it out clearly. DO NOT GO NEAR MAX loads with a most auto pistols, especially the Glock. Berry bullets shoot just like lead cast bullets without any leading. RS states max load for 180gr lead @ 5.7 TB. You where 6.0. That's .3 grains over max in a glock. I'm guessing your pressure PSI was way past 35,000. Yes, the case failed but it also blew the primer out. That is a sure sign of way to much pressure.

To much powder. That's all. Nothing scientific on what happened.

I guess I'm left asking why the berry's site states to use mid range FMJ data. I was way below that. Live and learn I guess.

Posted: 10/29/2009 1:47:05 PM EDT

[#26]

I've always treated plated bullets such as Berry's, Rainier, West Coast (Extreme), etc. as I would lead. They do have a thin jacket plated on them, but they aren't the same as a true jacketed bullet. I've had less than stellar performance from them as well. I prefer polymer coated bullets lately. Precision, BBI and Bear Creek are some of them that I've used and been very satisfied with. I load them to lead spec as well.

Posted: 10/29/2009 2:37:55 PM EDT

[#27]

I guess I should repeat this, you did not load mid range. 6.3 was the minimum you showed for jacketed. You made up your own load. Light loads have and can blow up guns as well. Stick to
the book.

Quoted:

Quoted:
Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

I'm laughing aloud right now. After the stuff I've read recently, you sure hit the nail on the head.

I've shot 1000's and 1000's of more than once fired brass out of my glocks. The speers book spells it out clearly. DO NOT GO NEAR MAX loads with a most auto pistols, especially the Glock. Berry bullets shoot just like lead cast bullets without any leading. RS states max load for 180gr lead @ 5.7 TB. You where 6.0. That's .3 grains over max in a glock. I'm guessing your pressure PSI was way past 35,000. Yes, the case failed but it also blew the primer out. That is a sure sign of way to much pressure.

To much powder. That's all. Nothing scientific on what happened.

I guess I'm left asking why the berry's site states to use mid range FMJ data. I was way below that. Live and learn I guess.

Posted: 10/29/2009 4:30:37 PM EDT

[#28]

Quoted:

Quoted:
Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

I'm laughing aloud right now. After the stuff I've read recently, you sure hit the nail on the head.

I've shot 1000's and 1000's of more than once fired brass out of my glocks. The speers book spells it out clearly. DO NOT GO NEAR MAX loads with a most auto pistols, especially the Glock. Berry bullets shoot just like lead cast bullets without any leading. RS states max load for 180gr lead @ 5.7 TB. You where 6.0. That's .3 grains over max in a glock. I'm guessing your pressure PSI was way past 35,000. Yes, the case failed but it also blew the primer out. That is a sure sign of way to much pressure.

To much powder. That's all. Nothing scientific on what happened.

OK, so if the OP would just drop a primer in the primer pocket of the fractured case, we could see the expansion effect of the overpressure first hand. Also, the extruded "new rim" at the case web should be explained somehow.

I was thinking perhaps the rim identified in the first two photos of the last batch (AKFF post 10/27 11:28) was caused by the jet reaction of the hot gas exiting to one side that drove the intact portion of the web perimeter on the opposite side out over the back and radially around the chamber. On the other hand, if the "new rim" was caused by pressure expansion radially of the web that much before the weak side of the case wall let go, then the primer pocket should definitely be oversize.

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Posted: 10/29/2009 5:33:29 PM EDT

[#29]

Quoted:
A squib round in the barrel would explain:
1) evidence of high pressure
2) possible out of battery firing
3) possible bullet set-back

I'm still thinking that unless the OP is 100% positive that the round prior to the KB exited the barrel, a squib is a strong possibility.

I am 100% positive that the round prior to the KB exited the barrel. Reasons below;

1- I was charting each individual shot. The shot before this went across the chrono, gave me a number and was charted.
2- I was watching to make sure I saw dust in the berm behind the target for each shot. My range sends up a dust cloud with each shot.
3- I was using the targets that go yellow when you hit it.

Those three things lead me to believe this was not a squib.

Respectfully,
AKFF

edited for spelling

Posted: 10/29/2009 5:56:02 PM EDT

[#30]

Quoted:

Quoted:
A squib round in the barrel would explain:
1) evidence of high pressure
2) possible out of battery firing
3) possible bullet set-back

I'm still thinking that unless the OP is 100% positive that the round prior to the KB exited the barrel, a squib is a strong possibility.

I am 100% positive that the round prior to the KB exited the barrel. Reasons below;

1- I was charting each individual shot. The shot before this went across the chrono, gave me a number and was charted.
2- I was watching to make sure I saw dust in the berm behind the target for each shot. My range sends up a dust cloud with each shot.
3- I was using the targets that go yellow when you hit it.

Those three things lead me to belive this was not a squib.

Respectfully,
AKFF

If you were chronoing the shots what did the KB show up as? That might be telling also.

Dolomite

Posted: 10/29/2009 6:51:58 PM EDT

[#31]

Quoted:

Quoted:
A squib round in the barrel would explain:
1) evidence of high pressure
2) possible out of battery firing
3) possible bullet set-back

I'm still thinking that unless the OP is 100% positive that the round prior to the KB exited the barrel, a squib is a strong possibility.

I am 100% positive that the round prior to the KB exited the barrel. Reasons below;

1- I was charting each individual shot. The shot before this went across the chrono, gave me a number and was charted.
2- I was watching to make sure I saw dust in the berm behind the target for each shot. My range sends up a dust cloud with each shot.
3- I was using the targets that go yellow when you hit it.

Those three things lead me to belive this was not a squib.

Respectfully,
AKFF

If you were chronoing the shots what did the KB show up as? That might be telling also.

Dolomite

OP noted that it was not recorded. He was distracted by the excitement of the day, and now regrets the oversight - though IMHO quite understandable.

I find this thread fascinating, and thank the OP again for posting what he probably is a little bit embarrassed by (i.e. a good gun blew up with my handloads, so I must have screwed up). My opinion on this matter is the OP most probably did not make an error. Glock .40 cal Kabooms are a well enough known occurrence, and even the Glock customer service staff are familiar with it and it's causes. Occam's razor (and the gaping hole in the SIDE of the casing) suggest this was a failure due to weakened brass and an unsupported chamber. It is possible that it was an out of battery failure, but I find that less likely. Some posters in the responses seem to indicate that the unsupported chamber is an acceptable design feature, and the user should modify standard practices to accommodate. I respectfully disagree. The Glock .40 cal design relies on the brass to act as more than just a gasket, but as a pressure retaining wall also.

Casings are not designed to be pressure vessels, but to be gaskets. Can you be 100% confident that you will never get a factory casing with a thin wall? Ever? In any other gun, such an occurrence would not even be noticed, much less explode.

As an engineer, I find Glock's .40 cal design philosophy unacceptable.

Posted: 10/29/2009 6:57:52 PM EDT

[#32]

Quoted:

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Good point on this one. I see what you are talking about, and the mechanics of it make sense. So at this point I feel like I can comfortably rule out squib, and potentially rule out an OOB firing. It's still possible, but that rim is not necessarily a sign of it.

Posted: 10/29/2009 10:00:52 PM EDT

[#33]

Quoted:

Quoted:

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Good point on this one. I see what you are talking about, and the mechanics of it make sense. So at this point I feel like I can comfortably rule out squib, and potentially rule out an OOB firing. It's still possible, but that rim is not necessarily a sign of it.

So was the primer pocket oversized? Did you drop a new primer in the blown case to see? If it was, the primer may have fallen out when you began examining the blown up gun. Your "hurry to get away" might very well have meant that you didn't notice.

But also consider that the AR10 is also very susceptible to a OOB. When I brought my brand new Remington R-25 (DPMS-built AR10 copy), Federal factory blue box ammo would chamber and fire the first round, and the next round wouldn't lock down...every time...had to be forced manually to close. Yet Remington cheap stuff, cycled perfectly. My reloads had to be sized with a small-base die to make it chamber reliably. What's my point? Who can prove the "almost KaBoom in the AR-10 wasn't a combination of OOB and too much powder. I still think a gun locked in battery is going to blow toward the weaker point of least resistance. By the time the round breaks away from the bolt head, the energy to create a lip like that would be long gone...through that hole in the case. If it's OOB then it's going to fire form anywhere it can before it finds the weak point to blow through. A case does that even in a normal shot out the barrel.

BTW AKFF, you must by now realize that your experience was as beneficial to the rest of us, as it was to you. I hope this thread encourages others who have bad experiences, to share them with us. Not sure the spook factor is quite the same to those of us experiencing this second hand, but it provides a serious wakeup call to all of us who dare to reload in the face of universal gun-manufacturer disdain for the hobby. I wouldn't have researched and checked out my Kahr quite so seriously, if not for your brave post. I posted the results in another thread just to encourage others to do the same for other semiautos. Anyway thanks!

Posted: 10/29/2009 11:13:18 PM EDT

[#34]

Unless I missed it, I don't see any report on the condition of the rest of the cases that were fired. Are they badly bulged? I find it strange that a substantial quantity of rounds are fine and then all of a sudden, one is so dramatically overpressure.

I can understand the blown case where it meets the feed ramp as possibly just a stressed piece of brass, but the blown primer in the mix just looks like higher than normal pressure to me. I still think there was something unique about the one round.

Posted: 10/30/2009 12:02:32 AM EDT

[#35]

Quoted:

Quoted:

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Good point on this one. I see what you are talking about, and the mechanics of it make sense. So at this point I feel like I can comfortably rule out squib, and potentially rule out an OOB firing. It's still possible, but that rim is not necessarily a sign of it.

So was the primer pocket oversized? Did you drop a new primer in the blown case to see? If it was, the primer may have fallen out when you began examining the blown up gun. Your "hurry to get away" might very well have meant that you didn't notice.

But also consider that the AR10 is also very susceptible to a OOB. When I brought my brand new Remington R-25 (DPMS-built AR10 copy), Federal factory blue box ammo would chamber and fire the first round, and the next round wouldn't lock down...every time...had to be forced manually to close. Yet Remington cheap stuff, cycled perfectly. My reloads had to be sized with a small-base die to make it chamber reliably. What's my point? Who can prove the "almost KaBoom in the AR-10 wasn't a combination of OOB and too much powder. I still think a gun locked in battery is going to blow toward the weaker point of least resistance. By the time the round breaks away from the bolt head, the energy to create a lip like that would be long gone...through that hole in the case. If it's OOB then it's going to fire form anywhere it can before it finds the weak point to blow through. A case does that even in a normal shot out the barrel.

BTW AKFF, you must by now realize that your experience was as beneficial to the rest of us, as it was to you. I hope this thread encourages others who have bad experiences, to share them with us. Not sure the spook factor is quite the same to those of us experiencing this second hand, but it provides a serious wakeup call to all of us who dare to reload in the face of universal gun-manufacturer disdain for the hobby. I wouldn't have researched and checked out my Kahr quite so seriously, if not for your brave post. I posted the results in another thread just to encourage others to do the same for other semiautos. Anyway thanks!

Thanks for your patience, I was not at home and unable to check the primer pocket.
Yes, the primer pocket was oversized and did not touch the sides of the primer. Also the headstamp is washed out.

So this leads me to my next question. Since that indicates overpressure, how much extra powder would cause this. Did I just use 6.0 when I shouldn't have? Or did I doublecharge or badly overcharge the case?

On another note, I spent today at the range firing reloads. Worked up 69 gr SMK BTHP and 55 gr FMJ for my AR15. Also confirmed what load I want to use in my .44 mag 240 gr HP loads. Everything went just as it should have.

I thank god for every day at the range that I do not blow myself up......I may finally have my sig line.

Posted: 10/30/2009 5:52:57 AM EDT

[#36]

Quoted:
BTW AKFF, you must by now realize that your experience was as beneficial to the rest of us, as it was to you. I hope this thread encourages others who have bad experiences, to share them with us. Not sure the spook factor is quite the same to those of us experiencing this second hand, but it provides a serious wakeup call to all of us who dare to reload in the face of universal gun-manufacturer disdain for the hobby. I wouldn't have researched and checked out my Kahr quite so seriously, if not for your brave post. I posted the results in another thread just to encourage others to do the same for other semiautos. Anyway thanks!

Yes, I applaud you for sharing this with us and likely causing us all to maybe pay a little more attention to the finer details. I have 9mm Glocks that I reload for and I'll be much more careful in the future even knowing this issue is usually more associated with the .40's.

I'm looking forward to hearing what Glock says once they've seen the gun and KB round (assuming your sending that piece of brass along).

Posted: 10/30/2009 6:31:49 AM EDT

[#37]

Quoted:

Quoted:

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Good point on this one. I see what you are talking about, and the mechanics of it make sense. So at this point I feel like I can comfortably rule out squib, and potentially rule out an OOB firing. It's still possible, but that rim is not necessarily a sign of it.

So was the primer pocket oversized? Did you drop a new primer in the blown case to see? If it was, the primer may have fallen out when you began examining the blown up gun. Your "hurry to get away" might very well have meant that you didn't notice.

But also consider that the AR10 is also very susceptible to a OOB. When I brought my brand new Remington R-25 (DPMS-built AR10 copy), Federal factory blue box ammo would chamber and fire the first round, and the next round wouldn't lock down...every time...had to be forced manually to close. Yet Remington cheap stuff, cycled perfectly. My reloads had to be sized with a small-base die to make it chamber reliably. What's my point? Who can prove the "almost KaBoom in the AR-10 wasn't a combination of OOB and too much powder. I still think a gun locked in battery is going to blow toward the weaker point of least resistance. By the time the round breaks away from the bolt head, the energy to create a lip like that would be long gone...through that hole in the case. If it's OOB then it's going to fire form anywhere it can before it finds the weak point to blow through. A case does that even in a normal shot out the barrel.

BTW AKFF, you must by now realize that your experience was as beneficial to the rest of us, as it was to you. I hope this thread encourages others who have bad experiences, to share them with us. Not sure the spook factor is quite the same to those of us experiencing this second hand, but it provides a serious wakeup call to all of us who dare to reload in the face of universal gun-manufacturer disdain for the hobby. I wouldn't have researched and checked out my Kahr quite so seriously, if not for your brave post. I posted the results in another thread just to encourage others to do the same for other semiautos. Anyway thanks!

Thanks for your patience, I was not at home and unable to check the primer pocket.
Yes, the primer pocket was oversized and did not touch the sides of the primer. Also the headstamp is washed out.

So this leads me to my next question. Since that indicates overpressure, how much extra powder would cause this. Did I just use 6.0 when I shouldn't have? Or did I doublecharge or badly overcharge the case?

On another note, I spent today at the range firing reloads. Worked up 69 gr SMK BTHP and 55 gr FMJ for my AR15. Also confirmed what load I want to use in my .44 mag 240 gr HP loads. Everything went just as it should have.

I thank god for every day at the range that I do not blow myself up......I may finally have my sig line.

That's the million dollar question. In a rifle cartridge with lots of space, there's a little room for error. Flat primers and partial head separation comes first unless the load is doubled. Pistol cases don't follow that scenario. On the little pistol cases like .380, 9mm, 40, etc. a few grains of powder, along with a bullet pushed into the case 1/16" too far. Well you get the picture better than I do. Then add a possible OOB. How could you not have a kaboom? For that last scenario all it takes is one case out of 100 that won't quite seat. IMO the Redding push thru die is cheap insurance against that one.

Posted: 10/30/2009 6:48:49 AM EDT

[#38]

I'm a complete noob to reloading. I've been around guns for a while and most of those have been Glocks. I've seen lots of KB pics. The one thing that strikes me about yours is the LARGE area of the casing that blew out. I've seen unsupported blowouts and some have been very thin "slits". The size of that makes me think there was in fact some type of set back that caused the round to not fully seat and you had a ever so slight OOB....which is why such a large portion of that case was blown out.

Again, I'm a complete noob so take my .02 for what they're worth (less than 2 cents

)

Posted: 10/30/2009 8:48:10 AM EDT

[#39]

Quoted:

Quoted:

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Good point on this one. I see what you are talking about, and the mechanics of it make sense. So at this point I feel like I can comfortably rule out squib, and potentially rule out an OOB firing. It's still possible, but that rim is not necessarily a sign of it.

So was the primer pocket oversized? Did you drop a new primer in the blown case to see? If it was, the primer may have fallen out when you began examining the blown up gun. Your "hurry to get away" might very well have meant that you didn't notice.

But also consider that the AR10 is also very susceptible to a OOB. When I brought my brand new Remington R-25 (DPMS-built AR10 copy), Federal factory blue box ammo would chamber and fire the first round, and the next round wouldn't lock down...every time...had to be forced manually to close. Yet Remington cheap stuff, cycled perfectly. My reloads had to be sized with a small-base die to make it chamber reliably. What's my point? Who can prove the "almost KaBoom in the AR-10 wasn't a combination of OOB and too much powder. I still think a gun locked in battery is going to blow toward the weaker point of least resistance. By the time the round breaks away from the bolt head, the energy to create a lip like that would be long gone...through that hole in the case. If it's OOB then it's going to fire form anywhere it can before it finds the weak point to blow through. A case does that even in a normal shot out the barrel.

BTW AKFF, you must by now realize that your experience was as beneficial to the rest of us, as it was to you. I hope this thread encourages others who have bad experiences, to share them with us. Not sure the spook factor is quite the same to those of us experiencing this second hand, but it provides a serious wakeup call to all of us who dare to reload in the face of universal gun-manufacturer disdain for the hobby. I wouldn't have researched and checked out my Kahr quite so seriously, if not for your brave post. I posted the results in another thread just to encourage others to do the same for other semiautos. Anyway thanks!

Don't call your DPMS an ar10. The parts don't interchange, it's not the same gun. And if you didn't pull the trigger and try and fire out of battery what makes you think it will? You simply had
a failure to feed.

Posted: 10/30/2009 11:57:18 AM EDT

[#40]

Quoted:

Quoted:

The "new rim" can also be seen in another "almost" KaBoom caused by overpressure for sure.
http://www.ar15.com/forums/topic.html?b=6&f=42&t=292135

Good point on this one. I see what you are talking about, and the mechanics of it make sense. So at this point I feel like I can comfortably rule out squib, and potentially rule out an OOB firing. It's still possible, but that rim is not necessarily a sign of it.

So was the primer pocket oversized? Did you drop a new primer in the blown case to see? If it was, the primer may have fallen out when you began examining the blown up gun. Your "hurry to get away" might very well have meant that you didn't notice.

But also consider that the AR10 is also very susceptible to a OOB. When I brought my brand new Remington R-25 (DPMS-built AR10 copy), Federal factory blue box ammo would chamber and fire the first round, and the next round wouldn't lock down...every time...had to be forced manually to close. Yet Remington cheap stuff, cycled perfectly. My reloads had to be sized with a small-base die to make it chamber reliably. What's my point? Who can prove the "almost KaBoom in the AR-10 wasn't a combination of OOB and too much powder. I still think a gun locked in battery is going to blow toward the weaker point of least resistance. By the time the round breaks away from the bolt head, the energy to create a lip like that would be long gone...through that hole in the case. If it's OOB then it's going to fire form anywhere it can before it finds the weak point to blow through. A case does that even in a normal shot out the barrel.

BTW AKFF, you must by now realize that your experience was as beneficial to the rest of us, as it was to you. I hope this thread encourages others who have bad experiences, to share them with us. Not sure the spook factor is quite the same to those of us experiencing this second hand, but it provides a serious wakeup call to all of us who dare to reload in the face of universal gun-manufacturer disdain for the hobby. I wouldn't have researched and checked out my Kahr quite so seriously, if not for your brave post. I posted the results in another thread just to encourage others to do the same for other semiautos. Anyway thanks!

Don't call your DPMS an ar10. The parts don't interchange, it's not the same gun. And if you didn't pull the trigger and try and fire out of battery what makes you think it will? You simply had
a failure to feed.

Boy did we get up on the wrong side. I said, "DPMS-built AR10 copy" which it is. I did pull the trigger because I hadn't noticed it was OOB. Fortunately it didn't fire. Because they were federals with soft primer cups, I was spooked a little. I guess that's from shooting M1As. It's just not a good thing to have factory ammo that measures too fat near the web. Yes, I measured it, and it was fatter than Sammi specs. I emailed Federal and they said very sorry and wanted the batch # and aked me to ship the rest of the box and the spent ones I shot, back to them. So yes, it was a failure to feed. It was my first experience with an AR-10 style rifle, and I didn't really know whether the firing pin was a floating design or not. BTW, I don't care diddly whether you or I have one made by DPMS or Armalite, or anyone else. They're all Stoner designs no matter who copies them.

I did have to retract the statement above about AR-10 susceptibility. I had read an article in the Fulton Armory web site about that, a year ago. I couldn't find it again...and I suppose I could've mistaken info about M1-A's. Time to test my DPMS on the subject. I usually include my sources in my posts...that'll teach me to post past midnight. Normally I would've looked it up first. No excuse.

Posted: 10/30/2009 3:01:41 PM EDT

[#41]

I've been following this very interesting thread since it was started. The blowup shot may well be multifactorial––Glock 40 issues, questionable brass, 180gr bullets, possible bullet setback. But I can't get past the concept of an out of battery firing. Look again at the photo on page 4 of the three cases, with the ruptured one in the middle. The "new rim" is perfectly formed all the way across. The shot basically fire-formed a new rim at the point where the case failed to fully enter the chamber. Yes, it gave way at the weakest spot, but there was more case in the unsupported area than a fully chambered round would have had. That's how I see it, but I doubt that anyone will be able to pin this incident down with absolute certainty.

Posted: 10/30/2009 4:55:44 PM EDT

[#42]

GWis, sorry for not wording my statement more politely. I reread it and it was way too blunt. It didn't sound that way in my head.

Posted: 11/3/2009 1:18:16 AM EDT

[#43]

Quoted:
Glock 40 chamber support
Once fired brass from a Glock chamber
180gr bullets
Bullet setback
Kaboom

It was the perfect storm.

180 grain bullets in a Glock .40 will not cause the KB. Many competitive shooters use 180 and even 200 grain bullets in the .40 S&W all the time. I've personally loaded thousands of 185 grain Precision and 180 grain Zero bullets. Powder selection and charge just need to be adjusted accordingly. What caused the KB is pressure. I still don't understand how so many other identical rounds cycled fine through the pistol, but one, all of a sudden, exhibited such a drastic spike in pressure. Something else caused this. If not a squib, it had to be an overcharge, IMO.

Posted: 11/3/2009 5:38:34 AM EDT

[#44]

Quoted:
...............

I still don't understand how so many other identical rounds cycled fine through the pistol, but one, all of a sudden, exhibited such a drastic spike in pressure. .................

Setback, the neck tension wasn't enough to hold the bullet in place as the cartridge was forced up the ramp.

Cut the area inside the case in half and you've got a grenade waiting to go off.

Posted: 11/3/2009 6:58:29 AM EDT

[#45]

Quoted:

Quoted:
One issue caused by the Pro 1000. Occasionally a case mouth will get hung up and not enter the sizing die or expanding/powder die correctly then I have to reverse the handle a tiny bit to get the case re-centered. Once straight I re-reverse the handle and continue sizing.

During all this moving around it is easy to get cornfused and end up double charging a case. If (IF) this happened and you automatically seated a bullet w/o weighing the charge you could have a grenade loaded. I try to use a powder and charge that will overflow the case if doubled for just this reason. No KB's yet and it's been a few years but I have pulled a few suspect rounds.

I had read about the double charging problem, so I decided if there was a problem I would just remove that casing aside and break it down later into components and start over with it. I did not want to ever double pump the lever for just that reason.

As for the powder that does not allow a double charge, and can be used with lead, FMJ or plated, can anyone recommend one?

I have not read more than the first couple pages so forgive the post if it is redundant, but you are on the right track here...

A double charge is very easy to do. With a single stage press you will want to do a visual inspection of the level of each case in the loading block before seating the bullets. In a progressive, you want to pull that round out iof the shell head if for any reason you suspect a double charge could have happened,

Ideally, you will use a powder with enough bulk that a double charge will overflow the top of the case and make the condition obvious, especially with a progressive press.

Anytime you are using any comopnents that differ from those in the loading manual you want to be very careful and start with a reduced load and work up. Max loads are best reserved for new or once fired brass, especially in a thin walled pistol case and that is doubly true in any design that leaves the web of the case less than fully supported. The Glock 40 pushes this to the extreme and I personally am not a Glock fan. They are easy to operate and area good choice for firearms training as they are fairly idiot proof, but they are not the best choice for a shooter who plans to shoot a lot and reload.

Posted: 11/3/2009 9:01:49 AM EDT

[#46]

Quoted:

Quoted:
...............

I still don't understand how so many other identical rounds cycled fine through the pistol, but one, all of a sudden, exhibited such a drastic spike in pressure. .................

Setback, the neck tension wasn't enough to hold the bullet in place as the cartridge was forced up the ramp.

Cut the area inside the case in half and you've got a grenade waiting to go off.

How has that been established as the cause of the KB? It would have been pretty severely set back to decrease the case capacity by 50%. The bullet must have been pushed nearly flush with the case mouth. Again, why was only one round subject to set back?

Posted: 11/3/2009 12:14:49 PM EDT

[#47]

Quoted:

Quoted:
...............

I still don't understand how so many other identical rounds cycled fine through the pistol, but one, all of a sudden, exhibited such a drastic spike in pressure. .................

Setback, the neck tension wasn't enough to hold the bullet in place as the cartridge was forced up the ramp.

Cut the area inside the case in half and you've got a grenade waiting to go off.

How has that been established as the cause of the KB? It would have been pretty severely set back to decrease the case capacity by 50%. The bullet must have been pushed nearly flush with the case mouth. Again, why was only one round subject to set back?

Just an educated guess, nobody really knows for sure what happened and we probably never will.

If you google bullet setback you'll come up with a lot of information about it.

Posted: 11/3/2009 1:20:35 PM EDT

[#48]

Quoted:

Quoted:
...............

I still don't understand how so many other identical rounds cycled fine through the pistol, but one, all of a sudden, exhibited such a drastic spike in pressure. .................

Setback, the neck tension wasn't enough to hold the bullet in place as the cartridge was forced up the ramp.

Cut the area inside the case in half and you've got a grenade waiting to go off.

How has that been established as the cause of the KB? It would have been pretty severely set back to decrease the case capacity by 50%. The bullet must have been pushed nearly flush with the case mouth. Again, why was only one round subject to set back?

Just an educated guess, nobody really knows for sure what happened and we probably never will.

http://i101.photobucket.com/albums/m54/nfe6848m/Maybe_Setback.jpg

If you google bullet setback you'll come up with a lot of information about it.

I'm very familiar with the term and the possible implications. I've been loading my own ammo for over 30 years and have associated with avid handloaders and shooters for the same length of time. I agree that setback is a possibility, as is a double charge. There are a number of possibilities.

Posted: 11/3/2009 1:27:45 PM EDT

[#49]

Quoted:

Quoted:
...............

I still don't understand how so many other identical rounds cycled fine through the pistol, but one, all of a sudden, exhibited such a drastic spike in pressure. .................

Setback, the neck tension wasn't enough to hold the bullet in place as the cartridge was forced up the ramp.

Cut the area inside the case in half and you've got a grenade waiting to go off.

How has that been established as the cause of the KB? It would have been pretty severely set back to decrease the case capacity by 50%. The bullet must have been pushed nearly flush with the case mouth. Again, why was only one round subject to set back?

Just an educated guess, nobody really knows for sure what happened and we probably never will.

http://i101.photobucket.com/albums/m54/nfe6848m/Maybe_Setback.jpg

If you google bullet setback you'll come up with a lot of information about it.

I'm very familiar with the term and the possible implications. I've been loading my own ammo for over 30 years and have associated with avid handloaders and shooters for the same length of time. I agree that setback is a possibility, as is a double charge. There are a number of possibilities.

Agreed, there are a number of possibilities.

I too have been reloading for more than 30 years.

I believe setback has a higher probability of being the cause in this case given what I have read and seen in this thread.

Posted: 11/3/2009 2:26:51 PM EDT

[#50]

I don't think the picture reflects anywhere near a 50% decrease in case capacity. While there seems to be a line midway on the blown case, you aren't taking into account the position where the bullet would be without any setback. I have loaded many rounds through the years that give a pretty good indication of the bullet base location. While the profile of the case clearly shows where the base is before firing, the inprint disapperars when the case expands after discharging the round.

Whether the shiny ring has anything to do with setback or not will likely never be known.

[ARCHIVED THREAD] - I blew up my Glock .40 with reloads - Help me figure out what I did wrong - UPDATE PG 4 - PLUS PICS (Page 3 of 4)

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