Glock 21 Kaboom. Why?

powwowell

Located in Deep Run, NC
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I had a really bad experience today. After around 95 rounds, my Glock 21 had a Kaboom. Really hurt my hands. Base of left thumb looks terrible. The top of my right index finger, near the knuckle is bruised and three minor cuts. Both hands were very painful for several minutes. The feeling gradually came back. I'm happy to report no serious, or permanent damage to my flesh.

The kaboom happened while shooting my reloads. From what I can see, the damage to my pistol is repairable. The magazine blew out and broke up. I found the mag tube, the follower and the base plate. The spring must be in orbit. I couldn't find it with the wife's help. And, a metal detector, and a magnet. The mag catch is split down the middle. It looks like these two pieces are the culprits that damaged my hands. The ejector may be bent? I know the ejector was funky looking, but I can't remember if it was bent to the extent it is now. The slide seems to be alright and the barrel is not bulged, nor ringed. I might see something when I clean it. Might be a day, or two?

After looking at the pictures, what do you think. Double charge, or it Fired Out of Battery?

Broken components.jpg
Shell 1.jpg
Shell 2.jpg
Shell 3.jpg
Ejector Bent.jpg
 
Almost like a double charge combined with some thin walled/weak(ened) brass. How many times had it been fired? If you’re like me you probably don’t know in regards to bulk pistol

What bullet and charge are you shooting ?
 
Ouch! Glad you're ok other than the minor stuff.

I don't know about the glock bits, but how many firings on the brass and what powder and charge were you set up for?
 
Lead bullets? That primer doesn't look like a double charge.
 
Not over five or six reloads for the brass. I think! 5.3 grains of HP-38, under Precision Delta 230 grain FMJ. OAL of 1.265. CCI LP primers.

I'm thinking maybe I should get out of reloading!
 
They are the best pics I can get with my camera. I'll try again tomorrow.
 
To me it looks like another case rupture due to Glock's unwillingness to use a barrel that fully supports the case in the G21 series. Look at the case and it's obvious. This is the part of the case that was over the feed ramp, I guarantee it.

As for the stoutness of your reloads contributing to the blowout....I'll not speculate, I'll leave that up to you to research.

This is one reason LAPD pulled the G21 off the street and sooo many LAPD officers that wanted to continue to use a .45 service pistol were allowed to return to the S&W4506 & 4566 upon going back through Gunfighter/decocker course and quals. Shortly thereafter, Chief Beck also allowed patrol division to carry 1911s once they had been through the Gunfighter/SA auto course.
 
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5.3 gn HP38 is a max charge by my book. Could have beeen an overcharge - 45 ACP is such a low pressure round that the primer might not show it. Pull a few and weigh the powder on a different scale.

Also looks to me like it failed at the feed ramp. What gen Glock is it?
 
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It's a Gen. 4. Reloads were done on a Lee Classic Turret press. The .49cc cavity dispenses 5.26 grains of HP-38/Win231, just like clock work. Verified on two different scales. I have loaded and shot hundreds of these previously. Maximum charge varies, according to whose book is consulted. I now have a Hornady LnL that I'm getting ready to start using. After this experience, a powder lockout die will be considered, before I get started. I had planned to visually verify powder by looking through an empty station three. I have had thoughts this afternoon of retiring from reloading. Those thoughts will probably fade with time?

I found a You tube video that parallels my experience. Except he also had a cracked frame! His case was blown out exactly like mine. The primer show no evidence of over charging. I'm leaning toward the theory that weak brass, in a Glock chamber, resulted in the Kaboom. When all this is over with, I might go with after market barrels for my Glocks? Maybe it's time to try the M&P 2.0 pistols?
 
It's definitely possible to double charge with an LCT, but will 10.6gn fit in the case? A visual check on the powder charge is a good idea no matter how reliable your equipment appears to be.
 
5.3 gn HP38 is a max charge by my book. Could have beeen an overcharge - 45 ACP is such a low pressure round that the primer might not show it. Pull a few and weigh the powder on a different scale.

Also looks to me like it failed at the feed ramp. What gen Glock is it?

Yep, I've seen 5.2-5.3 max in three different manuals. Only Hornady is higher, but their book seems to show higher for most loads.
 
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Powwowell, I like the idea of an aftermarket barrel. Been thinking about one.

I am not too worried about the Model 30 or 19 but the 23 is a different story. If I change the barrel in the 19 it will be because of the rifling.
 
Seeing the cutout for the feedramp you might be able to tell pretty quick if it was out of battery.
 
I've been following a thread in another forum where a guy blew up his Shield, using remanufactured ammo. IIRC, the conclusion was that the casing was either weak or reloaded more than once. I also believe someone mentioned that this is more likely to happen with Glocks because of something related to how much support there is for the bullet in the chamber. Does that sound right?

In the case of the Shield, the entire gun was destroyed but the ammo manufacturer agreed to replace it.
 
The barrel ramp and ruptured brass.
Barrel & Cardridge 1.jpg

My hands this morning.
left hand.jpg

Right Hand below.
right hand.jpg
right hand 1st.jpg

Gonna get a mag release and see if the pistol functions correctly with factory ammunition. If so, I'll get a after market barrel that offers more support and have at it again. The slide and frame seem to be OK.

The hands are not as sore as I expected them to be. A little tender though. I feel fortunate that the damages are minor.
 
You're a lucky man!!!!
 
So what happened? Hot loads? Glad you are OK!

*** nevermind... Just saw other thread. But still glad you are OK. :)
 
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Powwowell, I like the idea of an aftermarket barrel. Been thinking about one.

I am not too worried about the Model 30 or 19 but the 23 is a different story. If I change the barrel in the 19 it will be because of the rifling.

I tried that but it never ran right with an aftermarket bbl. So I *gasp* shot lead through my stock glock 19 for years until I switched to coated. In ~7k rounds I had no leading whatsoever but I had to clean it more often than I like to do.

I've been pondering this Glock feed ramp issue and my engineer brain tells me it may be a GOOD thing. If you design a fully supported chamber that locks up tight as a drum and then put a double charge in it, then when it fails the whole gun comes apart. If you design a fail safe into a system so that it will blow out and down, away from the shooter's hands, you can survive a ka-boom with just a few scratches and soiled drawers. I don't know if it's intentional or not... I'm just speculating.
 
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Bullet setback might be a possibility. You could check the case thickness at the mouth, a thin case doesn't crimp as much as a thicker one.
 
I've been pondering this Glock feed ramp issue and my engineer brain tells me it may be a GOOD thing. If you design a fully supported chamber that locks up tight as a drum and then put a double charge in it, then when it fails the whole gun comes apart. If you design a fail safe into a system so that it will blow out and down, away from the shooter's hands, you can survive a ka-boom with just a few scratches and soiled drawers. I don't know if it's intentional or not... I'm just speculating.

The chamber support (or lack of) in the Glock platform is to increase reliability. Nice big ol' hogged out chamber and feed ramp that will "eat anything" is the function behind the design.

I can't see any engineer purposely designing something to fail better.

The only Glock with fully supported factory barrels are the .357sig line due to their high pressures.

After looking at the pictures, what do you think. Double charge, or it Fired Out of Battery?

Based on your photos it looks like the brass failed where you get a typical "Glock Smile" in brass. If i had to wager a guess I'd say a combination of too much powder, worn brass and a notoriously unsupported chamber.

You ejector looks normal. Large frame Glocks of the .45 and 10mm variety both have funky bends in them like that.

As general rule of thumb, if you are reloading for Glock get an aftermarket barrel. Personally, I like KKM. Further, if you are recycling brass from the OEM Glock barrel you are likely using brass that has already been "abused" by the lack of support.
 
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Nope, you won't see it if it's done right.

Like car bumpers designed to spread impact out over time during a collision, right?

I see what you are saying, but I would think their objective is "consistent chambering to avoid failure" rather than "let's make sure if it fails it doesn't blow up his hand" The latter would be a byproduct of the first.
 
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