Glock 20 10mm Auto KABOOM

A ARFCOMer noticed the spent cases from his 1994-vintage Glock 20 (10mm Auto) appeared to be very close to failing (see case photo below). The problem seems to be that the rounds were not sufficiently supported by the chamber. A replacement factory barrel gave the cases a lot more support. He decided to do some tests at the range with his old barrel … you know where this story is going … the second round caused a catastrophic failure. The magazine and part of the frame were blown out. Fortunately he only suffered very a very minor injury.

Original barrel (left) and replacement.
Bulging 10mm Auto Case.

The moral of the story is not to shoot guns that are known to be unsafe. If you have to, construct a rig that allows you to remotely fire the gun from behind cover.

[ Many thanks to jdun1911 for emailing me the link. ]

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


  • Lance

    Never switch parts back and fourth use what works.

    • Ramsey

      If that was the case we would still be using blunderbusses. The person who had the KB was trying to determine if the problem was with the barrel or with recoil induced case setback. That is a valid test, he was just foolish to fire it by hand instead of with a standoff.

  • Al

    Stick with original Glock parts!!!!!!!!!

    • Ramsey

      You mean the original Glock part that allowed the KB? I think the aftermarket worked a little better in this case.

  • 18D

    It was the Glock barrel that failed. It is well known that Glock does not use barrels with total support for the case. With that said, the owner did the right thing by buying a new barrel for a high pressure cartridge like the 10mm. Glock’s in .40 and 10mm have always been somewhat dangerous with hot loads. Moral of the story is to buy an aftermarket barrel for your 10mm and .40 Glocks.

  • Mechman

    Glocks in 10mm, .40, and .45 are known for having a tendancy to go boom.
    It’s a known issue, and something that helped me decide on whether to go with glock or beretta when I got a .40 myself.
    Further information at

    • W

      all handguns have a tendency to go kaboom, though glock has saturated the law enforcement and civilian market to such a degree that lessons are being learned and the capabilities of the pistol are being pushed to the limit. for example, if you sell 10,000 of X-brand pistol, versus 1,000 of Y-brand, if X-brand experiences more kabooms (say 500), and Y experiences less (100), that doesn’t necessarily mean Y is “better” and less prone to destruct.

      • 18D

        That’s true, but Glocks chambered in .40 and 10mm are very likely to go KB if full house loads are used. Glocks have a much higher tendency to KB than many other guns on the market. Whether your shooting full house 10mm or .40+p loads, or standard factory stuff, you better look for pressure signs in a Glock!

      • W

        I will not agree. Indicating my (and a lot of other people’s) experiences with Glock, they are no more likely to KB than any other brand. incorrect hand loads will destroy any other brand of handgun and a lot of Glock 40, 45, and 10mm’s supposed problems are all hearsay without any empirical evidence. Handguns these days are pretty comparable in terms of reliability and durability.

      • 18D

        It has nothing to do with reliability and durability. It has everything to do with using barrels that expose the bottom base of the case with high pressure loads and having undersprung recoil guide rod assemblies. The issues with 10mm and .40 S&W Glocks are well documented. That’s why many shooters buy aftermarket barrels that DO have a fully supported chamber. If a shooter wants to use heavy loads with a factory Glock, then he needs to look for pressure signs since they have a high tendency to KB. Just the facts.

      • W

        how can it not? if a handgun has low durability, then it cannot sustain shooting 10mm ammunition for very long before failing. All of the users of the 45 and 10mm glocks rightfully trust their weapons to function and not let them down when it matters. I would like to see this “evidence” of the 40 and 10mm being inadequate.

      • 18D

        “How can it not?” You totally missed the context.

        Anyway, I don’t know what to tell you. Mechman’s link is a good link supporting my facts. It’s one of MANY stories, reports, accounts, and case studies on the net about the .40 and 10mm Glock’s well known KB issues. There isn’t much to debate with you about. The problem is COMMON KNOWLEDGE in the firearms community. All I can say is read and research the subject. There are many ammo manufacturers and ammo reloading guides that talk about the unsupported .40 and 10mm Glocks being unsafe for use with full power 10mm or .40+p ammo. The fact that the .40, 10mm, and .357sig Glocks are undersprung is also common knowledge.

        It’s important for shooters using Glock’s chambered in .40, 10mm, and .357 Sig to pay attention to pressure signs when using a factory barrel and full or extra power loads. The easy and inexpensive fix is to buy an aftermarket barrel with full case head support and add a stronger recoil spring.

        • James Clements

          I always add a 21# or 22# spring for my 10mm’s. As far as aftermarket barrels, no one has mentioned feeding issues with the aftermarket barrels. If the tolerances are tighter in the aftermarket then there are going to be more FTF’s.

    • Kirk

      One article on a pretty biased site, and you condemn the gun? Despite the owner of it acknowledging that he was shooting extremely hot ammo, and he shows severely bulged cases from before the gun blew up?

      Look, Glock may not be perfection personified, but the analysis you’ve done on this issue is fatally flawed by a lack of knowledge. Glock designed the 9mm frame to be quite overbuilt (I’ve fired mis-identified surplus carbine ammo out of my 19, which was responsible for breaking three other guns I know of. The G19 took that crap in stride for 500 rounds), and so was the 10mm frame.

      What went wrong was that Glock chose to buy into the idea with the .40 S&W that they could chamber it in a 9mm frame with no problem. History shows that’s BS, because boring out the barrel and not designing the lock/recoil system around the .40’s pressure curves has led to the problems we’re all familiar with those Glocks having. The 10mm/.45 was the same deal–Once Glock figured out they could do a .40 (barely…) on a 9mm frame, they decided to do the same thing on the 10mm frame, and chambered it for a .45.

      Both the .45 and the .40 are resultantly much weaker guns than the 9mm and 10mm. Which is why those two cartridges have most of the problems. Hell, I’ve personally witnessed a guy in training who fired a second round out of his G17 after one squibbed. All that happened was an ever-so-slight barrel bulge, as the second bullet drove out the first. Try that with your S&W Model 39…

      The main reason you see so damn many 10mm Glocks having issues isn’t that the gun design is weak–It’s one of the few built from the ground up on the 10mm platform–But that the cartridge is one that almost encourages a lot of hand-loading, due to the rarity and lack of variety in available loadings. Plus, it attracts a certain number of “…let’s turn the volume to 11!!!!!…” types. This tends to lead to a bunch of abused guns letting go. This factor is what leads to many folks including the 10mm as a problem Glock, and quite unfairly.

      • W

        “But that the cartridge is one that almost encourages a lot of hand-loading, due to the rarity and lack of variety in available loadings. Plus, it attracts a certain number of “…let’s turn the volume to 11!!!!!…” types. This tends to lead to a bunch of abused guns letting go. This factor is what leads to many folks including the 10mm as a problem Glock, and quite unfairly.”

        YES!!! finally. somebody that’s tracking the true problem at hand. the same thing can be said about a overwhelming majority of catastrophic explosions.

    • W

      yeah i still don’t buy into internet articles for facts. If Glock issued a giant “oh s–t, stop shooting!” recall for those models, then i would be convinced. otherwise, i take rumors with a grain of salt and unsubstantiated “facts” as BS.

      • fw226

        W: Out of curiosity, why are you here?

      • W

        well, normally such a stupid question doesn’t deserve a answer, though ill play ball. This blog in particular is the most objective, unbiased one in regard to firearms. That being said, ill call BS anywhere i see it. People deserve good information.

      • 18D

        Glock issuing a statement or recall? LMFAO! Gaston Glock believes his gun is the most perfect design ever developed. That company is not going to issue any kind of statement. Even with all the problems with the Gen 4 models, they still didn’t admit any fault. Instead they just said that they had a better solution for the recoil guide rod assembly.

        The problems with the .40 and 10mm models are not unsubstantiated claims.
        They are documented facts collected over years and years of experience with the gun. You don’t even have to take my word for it. Just look at any Glock and you will see the problem. Although, it sounds like you’re not a Glock shooter, so I’m sure it doesn’t matter anyways. I just don’t know why your resisting good information that could help you out if you ever decide to start running a Glock.

        You’re right when you say that people deserve the right information. Here it is right in front of you!

      • W

        “Glock issuing a statement or recall? LMFAO! Gaston Glock believes his gun is the most perfect design ever developed. That company is not going to issue any kind of statement. Even with all the problems with the Gen 4 models, they still didn’t admit any fault. Instead they just said that they had a better solution for the recoil guide rod assembly.”

        hmmm, seems pretty far fetched to me. I don’t particularly believe in conspiracy theories, especially with firearms. Honestly, I think any ideas that Gaston is deliberately hiding issues with firearms is a load of bull. Without any empirical evidence of systematic failures of handguns, these accusations increase the intensity and volume of bull that is shoveled into the even larger pile of bull. Hearsay and emotionalism are not the most compelling ways to prove a point…

        Problems with Gen 4 Glocks? the only “issue” i have heard was the recoil spring, which actually isn’t a problem because it allows hotter ammunition to be fired through the gun. I have had no issue with my Gen 4 19, and it has the first series spring (after firing wolf, PMC, and UMC ammunition).

        “The problems with the .40 and 10mm models are not unsubstantiated claims.”

        On account that tens of thousands of these pistols are used by a huge variety of different law enforcement agencies (state and federal), with millions of rounds of ammunition expended, nope, i have heard no systematic issues with those Glocks in those calibers, just a few odds and ends (like every other weapon).

        Since Glock has not done a major overhaul of Gen 4 guns (or even gen 3), that tells me that these “massive problems” that others so adamantly claim, were over exaggerations and, in many cases, user induced.

        Please, show me some credible numbers and perhaps ill consider changing my position. Lack of any evidence, citations, sources will lead me to call bullshit on emotional arguments. On account of these supposed “documentations” of kb’s, how many total are there for 10mm glocks? ill utilize your logic and come to my own conclusion: ten. Don’t like that number? well, i can’t back it, but they are ones i found from the internet, so that must be the total number. Apparently the internet is never wrong.

        “They are documented facts collected over years and years of experience with the gun. You don’t even have to take my word for it. Just look at any Glock and you will see the problem. Although, it sounds like you’re not a Glock shooter, so I’m sure it doesn’t matter anyways. I just don’t know why your resisting good information that could help you out if you ever decide to start running a Glock.”

        thank you for once again showing that you know nothing about me. I have been a Glock armorer and shooter for nearly ten years now. I think I have a little bit of credibility when it comes to Glock handguns. Never mind my experience; its the even more experienced people i know.

        Good information? it comes from the internet. Enough said.

        “You’re right when you say that people deserve the right information. Here it is right in front of you!”

        because it has to be right…it came from the internet. LMFAO.

      • Matt G.

        Come on guys, give it up. You will never be able to make a troll agree with you, that is the point. He wants your attention, all you can do is ignore him. His troll status is obvious, anyone who is experienced with glocks knows about the earlier unsupported chambers that slightly increased the chances of case failures.

        Of course, there is always the possibility that this is actually Gaston you’re talking to, as we all know he refuses to acknowledge flaws in his (perfection-even-though-we’ve-had-to-change-it-3-times-and-we-still-can’t-get-it-right)firearms. I love glocks like I love m&ps, but the fanboys are embarrassing.

      • W

        hmmm, i guess being a skeptic and questioning sensationalism gives you a “troll” status. hilarious. it should be no mystery why there is a continually strong anti-gun crowd: many pro-gunners sink down to their level and resort to emotional arguments.

        I’m still waiting for those credible numbers on the systematic failure of Glock’s unsupported chambers…

        Just to ask you matt, is there any firearm that has been unchanged from how it was originally designed?

  • Mike S

    The original feed ramp looks very polished, and material seem to have been ground of as well… Did someone try to fix a feeding problem or do all 10 mm barrels look like this?

    • Dan

      Unchanged gun design? 1911 of course, plastic is for little boys. Buy a real gun, besides a million dead nazis cant be wrong.

    • Dan

      After reading my own post I see that it sounds very confrontational, not meant that way just awnsering W’s question with the odvious awnser. The 1911 has been unchanged for over 100 years, why? Perfect, thats why. Argue all day about 10 vs 45 vs 40,this new plastic toy vs that one, whatever. The only PROVEN gun, cal combo is the 1911 in 45. Simple question, HOW MANY HUNDRED THOUSANDS OF OUR ENEMIES HAVE FALLEN OVER THE LAST 100 YEARS? Might not like lt fellas but THAT is not internet expert “I know every thing cause I read it on the web” but actual historical fact. Toys are great but carry a REAL gun when your tail is in a crack.

  • Mike S

    I think it looks like two different angles on the beveling (see my pic here

    Compare with these barrels (from

  • Komrad

    Scary. It could’ve ended much worse. 10mm is a very hot cartridge with factory ammo. Ammo loaded to the original specs are even hotter. I’m more surprised that we haven’t heard about this problem with 10mm Glocks sooner.
    If I remember correctly, it’s only older model Glocks that have this issue and the new ones are much safer. I almost wonder if Glock should do a safety recall on their old models to prevent this sort of thing.

    • 18D

      Actually most factory 10mm is watered down substantially. Factory 10mm these days is barely any better than .40S&W. But your right, ammo loaded to original specs is very hot. It’s very effective too.

      The Glock problem has been well documented for years. I’ve heard dozens of accounts of pressure signs and KB’s over the years. The new Glocks are little better if at all. The .40 S&W and 10mm Glocks are known to have unsupported chambers whether in an old gun or new one. Anyone that owns a Glock chambered in .40 S&W or 10mm should be very careful when shooting full house 10mm or .40 +p loads. It’s best to get an aftermarket barrel with full support if you wanna shoot these kinds of high pressure loads.

  • WoodenPlank

    The article states that BOTH barrels were OEM Glock barrels. I know that some changes were made to the .40 barrels to give better case support, so I would imagine similar changes were made to the 10mm barrels. Still not a good idea to use a barrel known to have issues, though, since the possible end result is obvious.

    • Tierlieb

      Yes, this article states it was a “replacement factory barrel”, but the linked one says it was an KKM barrel.That makes more sense.

      • J.T.

        Both barrels were factory Glock. One from 1994, the other from 2011. The 1994 one is the one that caused the kaboom.

  • probe

    Was the shooter right or left handed? I’m assuming right as a leftie could have suffered a serious thumb injury.

    VERY glad it was only i minor injury.

  • Milo

    ‘I figured it might be a dumb idea but I did it anyway,,,’
    Is it me or is society really dumbing down the farther we move into the 21st century??

  • Mu

    The old problem of tolerances. Max spec chamber, max pressure ammo, min thickness brass. Any two of the combinations would probably been fine, hit all three extremes and …

  • JM

    If I ever found out someone was “testing” a pistol or part that was known to be causing casing bulges on the same range as me, I’d throw an awful fit. Hopefully he did this on personal property and didn’t subject other shooters to Glock shrapnel.

  • Arifonzie

    To all glock fanboys- you don’t see this with a hk!

    • jdun1911


      He’s the brutal truth. Every firearms will go KB!. If you shoot a lot sooner or later you will experience a KB!

      With that said most gun owners will never have a KB! because at most they go to the range one or twice a year and shoot a total of 100 rounds or less.

      • Mark Are Reynolds Ⓥ

        In over 200,000 rounds loaded and fired in .25 auto, .380 auto, 9mm, .38 .38+p, .357, .40 S&W, 10mm, .357 Sig, ..44 magnum, .223, .308, 300 Win Mag, 50 cal, I’ve had THREE cases blow out. TWO were 9mm with the same kind of ammo out of the same batch in a Glock 17 that fortunately did nothing more than blow the magazine out of the pistol, and ONE was a .357 sig in a Sig P226 that blew the grips apart. Fortunately they glued back together nicely with wood glue. ALL THREE were out of battery ignitions. That is with over 200,000 rounds loaded and fired. I have a 4 gallon bucket that is full of spent primers 2/3’s full to prove it. I started filling it in 1977.

    • carter

      An open letter to the gun community from HK’s marketing department:

      In a world of compromises, some people put the bullets in the magazine backwards…But it doesn’t matter, because our gun is on the cover of the Rainbow Six video games. Look how cool that SEAL coming out of the water looks… If you buy a $2,000 SOCOM, you will be that cool of an operator too. And chicks will dig you.

      At HK, we stuck a piston on an AR15, just like a bunch of other companies have done, dating back to about 1969. However ours is better, because we refuse to sell it to civilians. Because you suck, and we hate you.

      Our XM8 is the greatest rifle ever developed. It may melt, and it doesn’t fit any accessories known to man, but that is your fault. If you were a real operator, you would love it. Once again, look at Rainbow Six, that G36 sure is cool isn’t it? Yeah, you know you want one.And by the way, check out our new HK45. We decided that humans don’t need to release the magazine with their thumbs. If you were a really manly teutonic operator, you would be able to reach the controls. Plus we’ve fired 100,000,000 rounds through one with zero malfunctions, and that was while it was buried in a lake of molten lava, on the moon. If you don’t believe us, it is because you aren’t a real operator.

      By the way, our cheap, mass-produced, stamped sheet metal guns like the G3 and MP5 are the bestest things ever, and totally worth asinine scalpers prices, but note that cheap, mass-produced, stamped sheet metal guns from other countries are commie garbage. Not that it matters, because you’re civilians, so we won’t sell them to you anyway. Because you suck, and we hate you, but we know you’ll be back. We can beat you down like a trailer park wife, but you’ll come back, you always do.

      Buy our stuff.


      HK Marketing DepartmentHK. Because you suck. And we hate you.

      • Komrad

        Really dude? I don’t care too much for H&K, but I’m not a dick about it. H&K may not have the best CS and they may not export all their stuff to the US, but that’s no reason to be an ass about it.

      • jdun1911


        I assumed you’re new to this. The joke that he posted is pretty famous in the gun community. It also pretty old.

        Do a search on “HK Marketing DepartmentHK. Because you suck. And we hate you.” and you know who wrote it.

        While it is a joke it is true that HK are overpriced decent firearms that have very little market penetration in the USA. Glock dominate the civilians and local LEA in the USA. It’s now started to take over the Federal government at the expense of Sig.

        The problem with HK is price. Their firearms is no better than a Glock or S&W. In fact I rank HK below them. For almost the price of a new HK you can by a new Glock AND a S&W AR15 ($519). A HK AR15 grip cost $80+ that is no better than a Magpul version (under $20). The fact is that everything that HK makes are over priced.

      • Mark Are Reynolds Ⓥ

        I found this on their site too. IT was in the why we don’t sell our great crap to the average working stiff. We only sell to the elite “law enforcers” of the world that force the ELITIST crap down your throats whether you like it or not.

    • W

      arifonzie, that is a stupid, baseless comment. Glock has earned a indisputably outstanding reputation among american law enforcement and gun owners. H&Ks are fabulous guns, though it seems to me most kabooms (especially with USPs or HK 45s) are caused by reloads and can destroy practically anything. Yes, if you know a gun is unsafe, take it to a armorer or gunsmith and have the parts exchanged and inspected.

    • surfgun

      HK, makes a 10mm pistol?

      • Lance

        No they make .40 S&W pistols though.

    • Mark Are Reynolds Ⓥ

      NO? Can you tell me what kind of pistol this is?

  • jdun1911

    I don’t have any experience with Double Tap ammo but I do find it amusing what DarkStar posted on the bottom of the first page.

    “the DoubleTap is indeed nuclear grade boom… ”

    From what I understand DoubleTap ammo are extremely hot that leave no room for errors. Good stuff. I might get some to test it out.

    • 18D

      I’ve been shooting Double Tap for many years now and its great stuff. They are one of the only companies out there that load true full power ammo. Their 10mm and .357 Sig loads are ridiculously powerful and accurate as hell. I’ve ran them over the chrono and the velocities are pretty much spot on with the specs they put out. Due yourself a favor and buy some Double Tap ammo for your carry gun. It’s the most effective defense ammo on the market.

      • Sky

        I have to agree, Double Tap has been amazing for my HK45. Super hot stuff but an absolute blast to shoot. Picked up a case of 230gr Speer Double Tao from someone who was clearing out their ammo closet.

  • Only gun I’ve never destroyed with a kaboom has been an all-steel 1911. It did crack and blow off a grip panel though.

  • Brian P.

    Well, I guess if I’m ever going to get a 10mm handgun, this rules out Glocks.

    • SpudGun

      @Brian P – This story has had the opposite effect on me. This guy fired thousands of hot rounds through his pistol for 17 years and only after he knew that a part was failing, did he deliberately keep shooting it until it blew up. Even then, he walked away relatively unscathed.

      I’m not a Glock fan, but I do respect it’s durability and reliability. The reason we see so many KBs of Glocks on firearm blogs is because a) there are so many of them out there and b) people are shooting them hard until they fail – and then shooting them some more.

      Out of curiosity, I’d love to see a marathon torture test between a Glock 10mm and a S&W K frame firing either hot .38 or normal .357 loads. It would be interesting to see which one failed first.

      • 18D

        It’s hard telling which one would fail first. It’s likely that neither would fail if both guns were brand new out of the box. The Glock however is more likely to go KB. The revolver isn’t subjected to the same pressure curve as the semi-auto design.

        I would like to see a 10mm Glock go up against a 10mm S&W revolver. That would be interesting.

    • mosinman

      i think the revolver would win , not because the glock is bad, but revolvers are good strong designs

  • carter

    I have a M29 same vintage and one gen 2.5. I checked both barrels and the feed ramps resemble the second barrel pictured.
    I think the first barrel is modified, it doesn’t resemble a stock Glock barrel. The apparent grinding/polishing ventures too deeply into the chamber.
    The moral of the story is, pick up your brass from time to time and check it out. If you see a problem that doesn’t mean you should just keep shooting.

  • Jim

    Is it just me or can anyone else here that bulging screaming loudly:

    “HEY YOU! Your gun just came thiiiiis close to going KABOOM!
    “WHAT? You wanna try a few more? ”
    “Well, Ok, it’s your hands and eyes….”
    “Lock & load!”

  • Matt G.

    The fact that this person is an arfcomer is no suprise at all.

  • Lance

    I don’t know about most but I know a guy who has a 10mm Glock and it never failed him. I have another friend who used Double tap ammo and it blew up his Colt Delta Elite pistol, yet is Caspian 10mm eats DT ammo like its great soft recoil ammo. 10mm and .40 are high pressure cartridges you better know what your doing when messing with it.

    • W

      yeah the 10mm is a incredible cartridge. The 10mm Glock’s only drawback is it is too large with people with smaller hands, though i don’t have a issue with mitts like mine. It is rightfully so a trusted self-defense cartridge.

      • John Doe

        I love the 10mm, but the Glock 20 is actually bigger than the standard-sized Glock (9mm, .40 S&W, etc.), just like the .45 versions. I got the 31 (.357 SIG) and I get similar power with less kick and more user-friendliness.

        • Mark Are Reynolds Ⓥ

          Similar power compared to the 10mm?

  • don dallas

    Am I the only one who thinks the chamber of the first barrel looks dremeled?

    • Mark Are Reynolds Ⓥ

      No. I see it too.

  • Ando

    That first barrel is absolutely modified. Glock barrels were never ground like that. 40 cal has pretty minimal case head support, as does 45. The support of the 10mm is not bad though. The longer profile eases feeding so less ramp is required. The brass tends to be thicker too. Recoil springs for the Glock 10mms are on the weak side, and a worn out recoil spring combined with the obviously modified barrel and a maximum hot Double Tap load has this not surprising result.
    Lesson learned. Don’t cut the ramp on your barrel! Get a stiff spring for full power loads. Don’t shoot stupid!

    • W

      outstanding assertion. I asked the same question when it came to the chamber ramp. I’m sure there’s more to the story now than what was told.

    • Mark Are Reynolds Ⓥ

      I agree with you. I use a 24 pound spring with my top end loads and a Bar Sto barrel.

    • Joseph Kool

      The owner insisted it was not modified

  • Ryan

    Why is it that only a few people are mentioning or even noticing the fact that the older barrel looks like it’s been overly dremeled?

    I feel like I’m taking crazy pills here!

  • Mobious

    More of a reason to wear gloves at all times, especially in unsafe condition/environment, and when you’re firing a gun that you suspect may not work perfectly.

  • Nicks87


    ^^typical internet response^^

    followed by:


    maybe one day we will evolve and get past all this nonsense.

    • W

      hahahaha don’t count on it. that would be too good to be true. but i read it on the internet… (LMAO)

    • mosinman

      fact is, any firearm can blow up. what happens everytime you fire a round? a controlled explosion of course : )

    • Mark Are Reynolds Ⓥ

      I will show you KB’s in H&K, 1911, Sig ETC!!! Screw up and double a Bullseye powder charge and say goodbye to your pistol. Can you say…BOMB in the CHAMBER?

  • Dave

    First, the original barrel in the photo was fired before the accident. And the barrel did not fail; the brass did. Complete case head separation blowing the magazine out the bottom.

    As the owner of the Glock in question, let me assure you I was the original owner, and I never touched the barrel with any tool. All of you who said it was obviously modified… you are wrong.

    If you look at the threads I started on the AR15 forum, or the GlockTalk forum, you will see SEVERAL people who have posted photos of their early second-generation G20 chambers that look IDENTICAL to my original barrel made in 1994. (the one on the left)

    The replacement barrel (on the right) was made in 2011.

    I have a third G20 barrel made in 2006 that looks different still.

    My point is, Glock has changed how they beveled the chamber of this barrel several times over the past two decades. Just because you haven’t seen one that looks as bad as mine, doesn’t mean someone must have taken a dremel to it.

    As I stated in those threads, my reason for posting the information was to be informative. I did not accuse or blame Glock or DoubleTap for the problem. I took full responsibility for the accident. Nobody was hurt beyond a small blood blister on my finger.

    Most people want to give me grief because I “knowingly used a defective barrel”. That isn’t completely accurate. I test fired because I suspected bullet set-back causing overpressurization, as described by other people in other forums. Had I known for sure it was the barrels unsupported chamber causing the bulge, I wouldn’t have done the test. I thought bullet setback was the cause, and the chamber simply allowed it to happen. There was a lot of detail in the AR15 thread that wasn’t provided here.

    • Trinity

      I have been using many Glocks since mid 1980s I have had natural concern for the kbooms and had one myself in a G30. Glock fixed it with a new barrel and lower just keeping the slide for 160$. They blamed it on the brass a Brazilian manufactured brand and recommended shooting only Winchester white box. Since then my step son an army ranger armorer sgt (sgt of the month lately) at Fort Benning have discussed the best we have knowledge of the real or more likely reasons for kbooms. I suggest every one interested in this look at the reasons for glocks or any pistol firing “out of battery”. My G30 obviously fired out of battery and this is acknowleged as a possibility by many sources. Just think about it and why it is possible as opposed to weak unsupported brass and barrel design. Kbooms happen with fully supported cases too you will find if you research it.
      One thing I found is that the G17 and I have a first generation with about 90,000 rounds through it do not kboom with a very few exceptions two that I know of.

      Should the firing striker be redesigned so it cannot contact an out of battery primer? Why does the Glock new short 45 still kboom with a fully supported heavier brass? Why is the 9mm the safest? What can be done and what does Glock know from science highspeed photography about what is happening when and when did they know it? A local PD was in the news as sending all their Glock 45s back recently?

      I have questions would like to hear from you and others about more than the narrower questions of unsupported brass. I think we should give more complete analysis to this kboom phenomenon, dont you?
      Meanwhile I love my Glocks and carry one. I admit I feel safest with the 9mm from 1980s (which has been back to glock and updated).

      • Mark Are Reynolds Ⓥ

        Make sure that you always chamber gauge any hand loaded ammo you are going to use in any pistol. I be that CBC Brazilian ammo was out of spec and allowed it to fire out of battery.

    • Mark Are Reynolds Ⓥ

      Double Tap makes ammo that is Bren 10 specs. I wouldn’t have used it in that barrel after seeing even one of those pieces of brass. And I accept your statement that it wasn’t altered as I’ve also seen early Gen 2 .45’s with crappy barrel support. I’ve sold ammo to folks and before they took possession I took their Glock apart and checked the support. If it had that bad of support I wouldn’t let them have the ammo unless I loaded it down to 950 FPS or less.

  • sean

    Does anyone one here know if any aftermarket barrel actually has the best chamber support for my glock 20sf and is the sf safe for medium loads,i haven’t had any glock smiles,but I stay on par with lee load data.thanks

    • Dan

      I know most of you guys dumped several hundreds in the “allighty glock” and to save face now feel the need to defend the 5 or 6 bills you dumped on a chunk of Wamm-O toy plastic that might blow up in your hand. I own the plastic xdm and enjoy it I must admit, however, when I leave the house ol reliable is what rides my hip. I KNOW WHEN I PULL THE TRIGGER THE ONLY “KABOOM” THAT HAPPENS IS THE GOOD KIND. can your cool, nifty,Gadston Glock Wamm-O make the same time proven, battle tested statement? No.

      • Ramsey

        This is a pretty ignorant comment. Most GIs never use their sidearm, as the best use for a pistol is to fight your way back to your rifle. If your reasoning was valid the whole world would be using AKs and M16/M4s until the end of history, if they ever moved away from swords, bows, and spears. Technology progresses, and I think more folks have died on the wrong end of a 9mm (or even a 22lr) in aggregate than with a .45.

        At one point the 1911 was a newfangled experimental design. Revolvers are more reliable, my muzzle loader was good enough for my grandpa, rifled barrels are for sissies, bows are the pinnacle of war, who needs these gimmicky bows when a spear is just as good, a real caveman uses a rock, etc.

      • Dan

        Oh and also moron, most of the world DOES carry the m16 and those who dont do carry the AK, keep in mind these people are soldiers who ACTUALLY use their arms against other soldiers. You sir, are an arm chair expert (all opinion, no experience)

        • Mark Are Reynolds Ⓥ

          The AK is a better design, in my opinion. Which doesn’t mean crap!

      • Ramsey

        You want to go there? I carried an M4 to shoot at guys with AKs. I also carried the M240B, the M9, the M249 SAW, the M203, the FGM148 Javelin, and helped hump the M224 mortar system. I was Airborne Infantry in the 82nd for 4 years, and have been on the wrong end of a muzzle before. I hope you are that mouthy in real life. I would love to hear about some veteran clocking you in the jaw.

        It took literally 1 second to find a 1911 kaboom that caused an injury.

        No weapon is perfect, no matter how much you might wish. They can all fail, and they can all be improved.

        I actually regret wasting my time responding to you. In your tone and your message you prove yourself to be unworthy of conversing with human beings. Good day, sir.

      • Derek

        Storm Lake makes excellent replacement barrels for Glocks with full case head support. I will also suggest you take a look at ammo from Underwoodammo d ot c om, if you want the REAL 10mm loads.

      • Mark Are Reynolds Ⓥ

        Try dropping your.45 from a helicopter up at about 1000 feet onto an airport runway and see if it works after you pick it up. Try laying it down and drive up in a car and slam on the brakes and skid your .45 under the tire and see if it still works after you pick it up. Try taking that .45 and throw it down as hard as you can on that tarmac and see if it works when you pick it up. I saw that done with a Glock 17 back in the 1980’s and that convinced me. The .45 he used as the demo against the Glock died when it was thrown down hard. The Glock hit the pavement so hard from the Helicopter that it bounced at least 30 feet into the air, and then it came down and bounced a few more times until the Glock rep picked it up and shot it. The sights were screwed up and the pistol was scratched and looked like crap but it fired EVER TIME after EVERY demo. The Colt died right away. I was there. I saw this and KNOW it to be true. No one told me about it.

    • Mark Are Reynolds Ⓥ

      Lee load data is fine, but way on the low end in many cases. Whatever you do, don’t load a .45 long colt with a 250 grain JHP using Lee data and then shoot it in your dad’s antique Colt DA revolver. The velocity is so low that the jacket will stay behind in the barrel…next shot the barrel starts bulging. Next shot it bulges more, finally after the top strap is stretched and the barrel is a 55 caliber, you can throw out the gun. The load is so weak you will be safe from a KB, but your gun will be trash. How do I know? Because a good friend of mine did this with his Dad’s Colt DA WW1 revolver!

  • Dan

    Holy crap, do the research. Start with “Blood and honor” the collective accounts of surviving german soldiers(if you can read) and read the accounts of the respect and fear of meeting a US soldier in the trenches (where most of the war was fought) and engaging in a small arms combat. Besides the rock and bow were replaced and improved, the 1911 is as it has been for 100 years. Don’t take it out on people with common sense because you wasted 5 bills on a toy that goes boom out the slide instead of the barrel. Besides dumb ass, PLEASE GIVE ME ONE RELIABLE ACCOUNT OF A 1911 HAVING ONE OF THE GLOCK FAMOUS KABOOMS. Oh, by the way I have a plastic car for sale for ONLY $500.00 you interested? Its kool and new and I read on the internet they are great so it must be true! Also the maker is selling them to law agencies all over the US for pennies on the dollar! More proof of their greatness. Does your daddy know you are on his computer?

    • Ramsey

      You want to go there? I carried an M4 to shoot at guys with AKs. I also carried the M240B, the M9, the M249 SAW, the M203, the FGM148 Javelin, and helped hump the M224 mortar system. I was Airborne Infantry in the 82nd for 4 years, and have been on the wrong end of a muzzle before. I hope you are that mouthy in real life. I would love to hear about some veteran clocking you in the jaw.

      It took literally 1 second to find a 1911 kaboom that caused an injury.

      No weapon is perfect, no matter how much you might wish. They can all fail, and they can all be improved.

      I actually regret wasting my time responding to you. In your tone and your message you prove yourself to be unworthy of conversing with human beings. Good day, sir.

    • Mark Are Reynolds Ⓥ This catastrophic failure was a barrel obstruction. Squib load put the bullet 2″ down the barrel and the next round BLEW it up. If you feel a weak load, make sure the bullet left the barrel. DUH? ANY pistol will blow up with this type of issue.

  • Dan

    Militry man with that much real world experience and you still choose a plastic weapon on which to defend your life? Ok, I give, I guess thats the difference between old military and new military. Thank you for your 4 years of service, I retired after 32 in 2006. Good luck with your choice of weapons. Semper Fi by the way, now that I have given away my age you can understand my my loyalty to the 1911

    • Ramsey

      What is with the hostility? I don’t even own a Glock. I respect the reliability and the huge leap in technology it represents, but I am buying a Kimber Solo for carrying and I shoot a .41 magnum S&W 57, a pre-64 model 70 in 30-06, a tuned 10/22, a 94 Winchester in 32 Special, and a whole mess of black powder. I appreciate technology and I respect history. If you love your 1911, more power to you. I am still eyeballing the SP1911 myself. I don’t feel the need to personally attack anyone because they chose something that I myself don’t care for.

      The 1911 is nearly unchanged for 100 years, great. A Glock is: lighter, cheaper, more reliable, higher capacity, available in more calibers, easier to repair, and more widely used. A 1911 is more accurate, sexier, more customizable, has a better trigger, shoots a freaking flying ashtray of a round, cycles faster, and wins more competitions. They both have their benefits, and it is no skin off my back which you choose.

      This is a fairly friendly forum, and most posters like it that way. You come across as very abrasive, and I don’t think it is warranted.

      • Mark Are Reynolds Ⓥ

        a 1911 is NOT more accurate. I’ve seen a Glock 21 with a Bar Sto barrel and match ammo fire 10 rounds through a 50 caliber hole at 25 yards from a rest that locks the pistol in it. I’ve seen a Wilson Combat a Colt Gold Cup and a highly modified by a hobby gunsmith.’s series 70 Combat Commander do the same thing. All of them were way more accurate than the owners.

    • Mark Are Reynolds Ⓥ

      It isn’t exactly a “plastic” weapon. It has steel in the areas that matter and the type of plastic that that is used is VERY resilient and stronger than you could imagine. Technology is bringing a lot of different materials into the market place that work great. The 1911 is fine and always will be.

  • Dan

    Apologies, just synscial ny nature, didnt mean any harm. I have extremly thick skin and assume others do too. allways have enjoyed a heated educated debate but making enemies was not my intent. Carry what you like, we all do. Recently I aquired a poly ar lower and could not be more impressed with it. I trust it completly as in fit and function its a milspec lower,its just lighter and stronger in material. Now were I called back to duty, I’ll take my service rifle, I KNOW that rifle and hve and allways will trust my life to it. Again just arguing my opinion based on my experience.I bear no ill will to anyone for their choice of pers protection. The glocks just scare me. It seems every time “glock” comes up, so does kaboom, especially in 40 and 10. Truth be known I have been waiting for a 10 in a 1911 for some time.

    • Ramsey

      Colt Delta Elite? Now that is a weapon everyone can agree is a special piece. It is a great joining of a beautiful machine with a century of history with modern, high pressure loading. I hate that the FBI was too recoil sensitive and went with the shorter 40. Ammo would have been way cheaper than it is now, and there would be more firearms chambered to fire it.

      My hat to you sir. Thanks for your service, you sure as hell did a lot more than me!. I bet we would both enjoy a beer or a day to the range together. It is so easy to read the wrong tone when conversing by writing.

      • Mark Are Reynolds Ⓥ

        The Colt Delta Elite did not have a fully supported chamber and would not support Underwood ammo type pressure without bulging the brass. I doubt if there is enough room to blow it out, but it will be once fired trash brass if you use those kinds of loads in a Delta Elite.

    • Andy

      My father retired from police work after 26 years a few years back. He has only ever had 2 pistols. An S&W model 64, which was replaced with a Glock 22. He has had his Glock 22, the same one, for over 20 years and has never had a single jam, misfire or “kaboom”. I’m not sure where your chip for Glocks came from, but you wrong, sucka!

    • Mark Are Reynolds Ⓥ

      The weak spot on the poly is the recoil tube area where it attaches. The rest is fine.

  • Roger

    Kirk is correct – there are too many doofuses out there handloading Glocks to dangerous levels, far beyond recommended maximum loads. Examine some Glock 20 handloading web sites and a knowledgeable reloader will be appalled at the stupidity represented there. It’s really amazing that they seem to get away with their dangerous experiments – which is a testimonial to the Glock design. If a person stays within recommended load data from manufacturers and experts with pressure testing equipment, he shouldn’t have any problems. I have a Glock 20 & a Glock 29, and they are good reliable pistols. I have a couple of .45s too, but the Glocks are much lighter and more powerful, and they hold way more ammo.

    • Mark Are Reynolds Ⓥ

      Glock also has a defect like every other pistol with that barrel type design of being able to fire out of battery. That may have also been the case here. Maybe the bullet was out of the case too far and was engaging the rifling, and exposing more of the case base in the ramp when it fired.SOMETHING caused that huge bulge and I’d bet money it was out of batter a bit when it went off. I’ve been able to fire my Glock doing tests with a primer in the case and pushing the slide back 1/8″ and it would still fire the primer. THAT sucks and can happen on a Glock, FN, S&W M & P, Springfield XD and Sig Sauer. ALL of those pistol use the same type of lockup as the Glock and can fire without the slide being all the way forward. ALL OF THEM. So hand loading your brass and being sure that the finished product will fit in a chamber gauge is also a good idea.

    • Joseph Kool

      You nailed it Roger, go to for a lesson in stupidity. I’ve never seen a bigger bunch of jackasses trying to hotrod a cartridge with such a lack of knowledge to begin with. Most of those clowns just got into reloading and they’re exceeding max book loads by 20 percent or more and they can’t understand why they’re getting blown primers and ruptured cases.

  • Mark Are Reynolds Ⓥ

    The problem also lies with the fact a Glock can fire out of battery. Glock’s perfection is missing a fully supported chamber and the inability to fire out of battery. I make sure my loads are all chamber inspected to do away with the firing out of battery issue and if the pistol has an unsupported chamber I replace the barrel with one that has a supported chamber.

  • James Clements

    I read a lot of people talking about an aftermarket barrel in these high powered Glocks but I’ve seen no mention of the tighter chamber tolerances causing FTF? We all know that tighter tolerances are going to be more finicky about the ammo it eats. Anyway, the only part I ever change on a Glock is the RSA. I use Wolff or Brass Stacker 21# in both a 21c and a 29.

    • Mark Are Reynolds Ⓥ

      I’ve never had and FTF with the ammo properly loaded to the right OAL specs with Bar Sto (.45 G21 .45 G30 .10mm G20 10mm G29) Wilson (.45 G21 .40 G22) or Storm Lake (.357 Sig G32, 9mm G17 9mm G19) Now if you have the bullet seated to high, yes, that can cause issues. But if you stick to specs…never seen a problem.

  • Rodolphe Grenier

    That’s a pretty early version, seeing the grip and non-presence of a picatinny rail

    • Mark Are Reynolds Ⓥ

      Gen 2

  • lenny46

    As a reloader, I have always studied my brass. Many weapons mangle the brass, so it is a good indicator something is wrong.

  • Mark Are Reynolds Ⓥ

    That case shows that SOMEONE had overcharged the case. I’ve fired many rounds that were “hot” in a Glock barrel. 11 grains of Long Shot behind a 165 Remington Golden sabre caused a slight bulging on 7 out of 13 cases. Notice I said SLIGHT. But it showed me to back off and I did. To 10.5. No bulging at all there and the velocity was still 1377 FPS vs 1404. After I installed a Bar Sto barrel that same 11 grains, it pushed the 165 Golden sabre at 1467 feet per second without showing ANY pressure signs on the brass. And obviously the Bar Sto barrel must have had more pressure in it to have that much more velocity. Glock claims that the “polygonal” rifling gives you more velocity. I’m here to say that is bs. The 10mm is a round that is typically underloaded with modern data. I use data from the early 90’s and it works fine. I watch for signs. This guy had some MAJOR pressure issues. I had some VERY SMALL SLIGHT bulges at 11 grains. I’d say someone used too much of some kind of powder. That pistol also may have had a badly supported chamber due to some gun butcherer “throating” the barrel. I mean LOOK at how much of that brass is bulged. WAY more than the typical amount that you would see from the typical area that is not supported.

    • John Pryce

      I handload my 10mm bullets, but when I try a new load, I do the FULL safety procedure, including the part where I test the rounds at the range, one bullet at a time, inspect the case after each round, AND field-strip my Glock to check for pressure damage after the testing session.
      Seriously, I’ve received ZERO formal instruction on handloading; literally I got started from a book and a few Youtube videos. But I was able to pick up on the importance of care and accuracy in loading procedures without issue; why is this so hard for some people?

  • Joseph Kool

    The problem is boutique ammo loaded to ridiculous pressure and ignorant owners who want to turn their 10mm into a 41 magnum because they’re idiots. Instead of paying up the @$$ for dangerous slopilly loaded boutique ammo buy a bigger gun you morons.