kB? only with Glocks?

Other calibers also KB. Do a search on my user name for a description of a KB in a G19.

Yes, other brands do KB.

In 1911's, KB's weren't very common until IPSC shooters started hotroding the .38 Super. Previously, when most 1911's were in .45, KB's were rare. Even when gunsmiths got real aggressive in throating barrels and leaving a lot unsupported chamber, there weren't a lot of KB's.

After Rob Leatham popularized the Super for IPSC, there were a number of occurances of "Super Face." Gunsmiths started using fully supported barrels, and the problem has pretty much gone away.

There are a number of factors that seem to contribute to KB's.

- Unsupported chambers
- Ability to fire out of battery
- Polygonal rifling and lead bullets
- Bullet set back
- Over charges

I am sure that there are others. These conditions aren't unique to Glocks. There are any number of pistols that can experience one or more of these conditions.

AFAIK, there has been no scientific study done that can provide us with any evidence. All we have are anecdotes. To make any kind of generalizations based on anecdotal evidence would be very foolish.

Oracle stated:

"Whenever I've read serious study of a Glock kB (and some other brand kB's) with .40 S&W ammo, it's been determined that the cartridge was either double-charged, or that the bullet may have been set back to far in the case."

And:

"I think those two reasons are the cause of most of the kB's (overpressure rounds due to double charge or bullet setback), that's the closest thing to a "unified theory of Glock kB's that I've seen."

I have asked the question before, and I'll ask it again:

How, after the fact, can it be determined that a round was double charged, or that there was bullet set back?

I maintain that after the round has been fired, determining either one of these two conditions is impossible. The bullet is gone, the case is blown. An after the fact examination is going to tell you there was a double charge or bullet set back? Hogwash.
 
Lee,

My original response to the thread was that it is possible due to the unsupported chamber that Glock factory barrels come with.

Now the reality is that if your using factory ammunition the chance of that happening is rather remote. It would occur mainly with reloaded, wildcat or defective factory ammunition.

I remember from the earlier days of IPSC competition, when shooters were transitioning to 38 Super to be able to meet power factor that was required at that time they had to load the cartridges a bit on the hot side those original 1911 barrels weren’t supported so problems manifested themselves.

So in a nutshell if a shooter were foolishly trying to wildcat some loads for use in a Glock that has the original factory barrel still installed they would be asking for trouble. If they were to replace it with a barrel that has supported chamber the problem would be lessened but not eliminated since an undetected SQIB load or a double charged load or using the wrong powder could cause a problem not just for Glock but any handgun currently in the market.

Hope this clarifies my earlier statements.
:)
 
gee leedesert, its like you are reading my mind. that was gonna be my next question!! now lets see, what are some other urban legends i can troll with?

j/k, but thanks for the input from everyone, i'll do some more research before i make up my mind.

and someone asked if i was nervous about revolvers as well as glocks without safeties. i dont have a definitive answer for that. a revolver is not something i ever see myself carrying for protection, but for the home, where i know my surroundings and am comfortable with such a firearm, its a different story.

tenatively, it looks like i would avoid any reloads with the .40, and use lighter loads. can the chamber be replaced in a glock?
 
Expert advice

I just called the tech guy at Glockmeister about the out of battery thing. He said it can't happen. I asked him how he knew that and he told me that Glock Inc. told him it can't. He recommended I call Glock.
 
Well, just called Glock. According to them, there is absolutely no tolerance for any rearward slide movement of any kind with engagement of the striker.

This is nothing short of incredible. While every other weapon has a tolerence of 1/16" or less, Glock has managed to produce a mechanical system with a zero tolerance. So if you can drop the striker on your weapon with even 1/32 of slide movement to the rear, you need to send the weapon to Glock:

GLOCK Inc. USA, Canada
6000 Highlands Parkway
Smyrna, GA 30082

I may have my 3 checked by a local smith before I dedicate the money to FedEx.
 
Handy says he never heard of anyone annealing the case head. Well, for heaven's sake, DON'T. I knew one guy who had read about annealing and who annealed the whole case when reloading for .308. Fortunately, the first shot blew the primer and spread the base all over the bolt face of his M1A, but no further damage was done. I say "fortunately" because the next one could have had complete case head failure and done a lot of damage.

Jim
 
You're right spacemanspiff>

Send those defective Glocks to this address:

***
***
***

And I'll replace those with some nice Lorcins, Ravens, and the like. Good quality metal guns. You know you like them.
 
Everyone has had a friend of a friend who had a Glock kB.

85% of the U.S. population over the age of 15 and under the age of 50 in 1969 went to Woodstock.

No one voted Richard Nixon for President of the United States in 1972.
 
...stick with a normal all steel Colt .45, and no KB:D
Click to expand...

That's why my buddy's 1911 let go. He needed an "all-steel Colt frame" and not an "all-steel Essex frame"... Gotcha... I always though it was a double charge. Thank goodness he'd just put Hogue wraparounds on it; I hear those walnut splinters cause infections... ;)
 
Help with KBs information.

Glocks carry unsupported chambers but so do a lot of other good guns such as the Beretta 92. This is NOT the primary issue with KBs.

The primary issue with KBs is case expansion whilst in the barrel. A barrel that controls case expansion carries less risk of a KB. When a primer is struck and ignites the gun powder an explosion takes place within the bullet case and raises the internal pressure in the bullet case. This pressure is translated into kinetic energy which drives the bullet head forward. Case expansion reduces some of this forward kinetic energy and if the case is weak (for e.g. a case that has gone through a number of reloads) and/or the barrel does not provide sufficient control on the case expansion then the case will rupture and that energy will be released within the gun and you have a KB.

Glocks are known for providing less case expansion support than other guns. Coupled with the unsupported chamber then this means that the Glocks are more prone to KBs. Note however that KBs can happen in any gun.

Polygonal-rifled barrels facilitates greater internal pressure within barrels becasue it provides a better gas seal. This is good in that it reduces kinetic energy loss and means higher muzzle velocity. It is bad in the sense that the greater internal pressure coupled with a weak or badly-loaded case that erupts or overexpands could cause serious problems. HK in using polygonal-rifled barrels in their USPs used a supported chamber to reduce the risk of KBs.

For any gun however always know your bullet specs. and load. This is a gun safety rule which is often ignored!.. or maybe not known?

A long thread but I hope it resolves my TFL members concerns and questions..:cool:
 
Worst Glock Kb photo I ever saw:



(Taken from Glocktalk.com)
 
C-

When a cartridge is fired, the case expands from the pressure. The chamber walls restrain it (er, presumably).

When the case has expanded sufficiently the bullet is released. Gas pressure then pushes the projectile.

Kinetic energy happens later.............
 
Handy:

I secong that suggestion - call Glock before you continue to post about your Glocks that will (supposedly) fire out of battery. If you don't know how to contact them, I'll tell you.

Call 770-432-1202. Ask for Chad Mathis - he is the supervisor of the Warranty/Technical Services department. Chad is often busy, so you may have to leave a message.

It's amazing:

1. Ben (at Glockmeister) has fired thousands of rounds through every Glock model ever manufactured (while in the Israeli Special forces and later as aGlock factory rep) and says this has never happened.

2. The Glock factory technicians say this can't happen.

3. YOU say it happens in your pistols.

Please forgive me if, for the time being, I rely on the experts. I DARE you to call Glock and give us a verbatim account of your conversation.

Dawg23

p.s. While you're talking to them, explain to them YOUR definition of "out-of-battery."
 
Dawg,

I did call Glock. It says I did in my last post. The conversation was short. As stated above, the technician said that the Glock, unlike other pistols, will not release the striker if the slide is ANY distance from completely full forward against the takedown latch.

Recoil pistols operate by locking the slide and barrel together for a certain distance of the slide's rearward movement. That distance translates into a period of time that is identical to the peak chamber pressure peak. Even if the locking lugs or equivelant are fully engaged, if the slide is not fully forward, the action will unlock too early. This is an "out of battery" condition.

I am, frankly, confounded by responses that insist that the Glock pistol has a zero tolerance firing system. I would love to handle a gun with that claim attached to it, as I'm sure some of you would like to see the 3 out of spec weapons I have.
 
I thought it was fairly well-established that the main KB issue in Glocks (and any gun with polygonal rifling) was use of ammo with exposed lead. Of course, this doesn't explain 9mm Glocks being KB- free . . . maybe more 9mm ammo is factory (due to cost) than .40 and .45?
 
Handy:

Sorry - I saw your post that mentioned glockmeister, but missed your later post about talking to Glock factory.

Also sorry, but I'll take their opinion over yours on the out of battery issue. Thanks for confirming that they state that this isn't a problem.


Dawg23
 
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