FWIW and unsuported chambers
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singleshot
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FWIW= for what it's worth
when the feed ramp of the barrel is cut too far into the chamber area it leaves some of the cartridge case wall unsupported. Too much and a case rupture can result. Certainly this isn't limited to Glock.
The easiest way to see if this is a problem is to examine a fired case. If there is a significant bulge in the case in the area of the feed ramp it may indicate a problem.
when the feed ramp of the barrel is cut too far into the chamber area it leaves some of the cartridge case wall unsupported. Too much and a case rupture can result. Certainly this isn't limited to Glock.
The easiest way to see if this is a problem is to examine a fired case. If there is a significant bulge in the case in the area of the feed ramp it may indicate a problem.
Postman,
You'll find lots of threads here about the Glock KB and unsupported case issue. The most notable handgun to have a partially unsupported chamber is the Colt 1911 series and contrary to popular belief, these guns also have had instances of "rapid dis-assembly", the problem mainly concerns Glocks chambered for .40, .357 and .45, the 9mm's have very few documented instances of KB's. Glock ran the feed ramp into the chamber wall and optimised the overall chamber dimensions and design to facilitate reliable cycling and extraction, and this certainly works. The KB problems are supposedly un-heard of if you avoid the following, reloaded ammo, lead bullets, powder AA#5 and possibly aluminum cartridge cases used on some practice rounds. Many documented KB's with standard pressure original factory FMJ's have been documented however and the argument as to the frequency of case/chamber failure will run forever, most Glock owners believe that it's just scaremongering, or worse, deliberate rubbishing of the new kid on the block. Most people I've spoken to seem to feel that the reloading issue has arisen due to people overcharging the cartridges to +P level or even double loads, but the latter will blow most any chamber, supported or not, and since the Glock is actually designed to function most reliably with +P rounds, this reasoning doesn't seem to scan. Rather, it is more likely to do with the possibility of the already weakened cartridge being fed into the chamber with the previously bulged case seated in exactly the same position, thereby greatly increasing the likelihood of it failing under pressure. Many, many people will tell you here about having fired countless thousands of rounds of every conceivable type of ammo through their Glocks without so much as a stovepipe, a few others will tell you about horrific hand or eye injuries caused by exploding .40's. FWIW my take on the Glock range is this, they seem to fire far to easily for safety with a hammer at half cock, a half inch 5.5 lb trigger pull and no positive (as opposed to passive) external safety, couple this with possible KB problems and a grip angle that makes me point the gun naturally high, and a Glock, at least for now, is not an option for me personally. Like I said before, many other contributors here will vehemently disagree with this appraisal, as will countless thousands of LEO's, but since you asked what the perceived Glock "problems" are, this is my $0.02.
Now remember you Glockenspielers we're all friends here.
Regards,
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Mike H
You'll find lots of threads here about the Glock KB and unsupported case issue. The most notable handgun to have a partially unsupported chamber is the Colt 1911 series and contrary to popular belief, these guns also have had instances of "rapid dis-assembly", the problem mainly concerns Glocks chambered for .40, .357 and .45, the 9mm's have very few documented instances of KB's. Glock ran the feed ramp into the chamber wall and optimised the overall chamber dimensions and design to facilitate reliable cycling and extraction, and this certainly works. The KB problems are supposedly un-heard of if you avoid the following, reloaded ammo, lead bullets, powder AA#5 and possibly aluminum cartridge cases used on some practice rounds. Many documented KB's with standard pressure original factory FMJ's have been documented however and the argument as to the frequency of case/chamber failure will run forever, most Glock owners believe that it's just scaremongering, or worse, deliberate rubbishing of the new kid on the block. Most people I've spoken to seem to feel that the reloading issue has arisen due to people overcharging the cartridges to +P level or even double loads, but the latter will blow most any chamber, supported or not, and since the Glock is actually designed to function most reliably with +P rounds, this reasoning doesn't seem to scan. Rather, it is more likely to do with the possibility of the already weakened cartridge being fed into the chamber with the previously bulged case seated in exactly the same position, thereby greatly increasing the likelihood of it failing under pressure. Many, many people will tell you here about having fired countless thousands of rounds of every conceivable type of ammo through their Glocks without so much as a stovepipe, a few others will tell you about horrific hand or eye injuries caused by exploding .40's. FWIW my take on the Glock range is this, they seem to fire far to easily for safety with a hammer at half cock, a half inch 5.5 lb trigger pull and no positive (as opposed to passive) external safety, couple this with possible KB problems and a grip angle that makes me point the gun naturally high, and a Glock, at least for now, is not an option for me personally. Like I said before, many other contributors here will vehemently disagree with this appraisal, as will countless thousands of LEO's, but since you asked what the perceived Glock "problems" are, this is my $0.02.
Now remember you Glockenspielers we're all friends here.
Regards,
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Mike H
Very good post, Mike.
There are two things that I would like to add if you permit me to
actually, you have no choice...)
1)It is my understanding that ALL semi automatic handguns have to have an unsuported chamber, and not just Glocks.
That's what makes the feeding of the round possible.
2)It is also my understanding that unfortunately Glock has the "widest" unsuported chamber, since they wanted this weapon to fire under extremly adverse conditions.......sand, snow, mud etc.
This was originally done for military and law enforcement reasons only, since Gaston designed the first glock for the AUSTRIAN military!!!
I agree with you that this may not be the best weapon for the regular, off the street John Doe.
But then again, it was never ment to be.
Here are my two Shillings worth.
(Austrian Shillings of course...Edward)
There are two things that I would like to add if you permit me to
actually, you have no choice...)1)It is my understanding that ALL semi automatic handguns have to have an unsuported chamber, and not just Glocks.
That's what makes the feeding of the round possible.
2)It is also my understanding that unfortunately Glock has the "widest" unsuported chamber, since they wanted this weapon to fire under extremly adverse conditions.......sand, snow, mud etc.
This was originally done for military and law enforcement reasons only, since Gaston designed the first glock for the AUSTRIAN military!!!
I agree with you that this may not be the best weapon for the regular, off the street John Doe.
But then again, it was never ment to be.
Here are my two Shillings worth.
(Austrian Shillings of course...Edward)
Also a lot of KB's may(?) be attributed to lead builup because of the Polygoal rifling & the laziness of the owners to clean their guns more often !
Seems that the Polygonal rifling tends to cause lead profectiles to smear & when the barrel gets obstructed enough...BOOM !
Last but not least are the ones that will supposedly fire out of battery !
This is when the slide is not fully closed & the base of the cartridge is less supported than usual.
Not a good design feature...
I did own a G-22 in .40 S&W and fired 1000's of lead handloads through it but I like a clean gun, so it was "fluffed & buffed" after every 300rnds.
My 5c worth as the Govt. here phased out 1 & 2c coins yearts ago.
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"The Gun from Down Under !"
http://www.para1911fanclub.w3.to/
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HS2000@ausi.com
Seems that the Polygonal rifling tends to cause lead profectiles to smear & when the barrel gets obstructed enough...BOOM !
Last but not least are the ones that will supposedly fire out of battery !
This is when the slide is not fully closed & the base of the cartridge is less supported than usual.
Not a good design feature...
I did own a G-22 in .40 S&W and fired 1000's of lead handloads through it but I like a clean gun, so it was "fluffed & buffed" after every 300rnds.
My 5c worth as the Govt. here phased out 1 & 2c coins yearts ago.
------------------
"The Gun from Down Under !"
http://www.para1911fanclub.w3.to/
Alternate E-mail
HS2000@ausi.com
OK , this is my take on this issue. I own a Glock Model 22 (.40 cal.) and a S&W Model 909 (9mm). I disassembled both pistols took the barrels and slipped a live round in each chamber. Both barrels had the same unsupported area in the 6 o'clock position of the chamber. To me the only hanguns to have truly supported chambers are revolvers.Yes their was a factory kaBOOM with Federal factory ammo, but that was due to case failure. Every caliber has its share of kabooms especially with handloaders who push the envelope and go with nuclear loads. Also the same thing with people who fire lead rounds in Glocks, H&K's, Kahrs and any other make that uses polygonal rifling. If you want to read good info on this read KaBOOM faq's by Dean Spier. I had the opportunity to communicate with him by e-mail on this very subject. Basically boils down to the fact , you have to follow the manufacturers guide lines, "No lead" means "No lead", "No re-loads" means "No reloads". Sorry this is so long.
protoolman
Moderator
Actually some straight feeding autos do have fully supported chambers. Also I liked Glocks and once carried one on duty until a friend blew one up that was always fired with factory jacketed ammo. It was sent to the Winchester lab for independant analysis and they concluded that it fired out of battery with normal pressure ammo. Well it split open along the front strap, lost the trigger never recovered.Blew the slide up off the rails in the back partially and split the back of the barrel. Damage to the officer was one badly blistered hand a a face full of hot gasses and a few shrapnel marks. Needless to say I carry a Ruger now I would (and do) bet my life on.
Bennett Richards
New member
H&K USP's have a fully supported chamber.
Ben
Ben
I am not flaming anybody's gun here. I to like Rugers, S&W's, H&K's and so forth. Just stating the only gun to have truly supported chambers are revolvers. I also have seen revolvers that have gone kaBoom. All guns have them, and most instances are traced back to user error. There was a certain lot# of factory Federal ammo that had weak brass, which lead to kaBoom's. The throated chamers in Glocks and 1911's and whatever gun you have a 'smith do it to is not a design flaw but incorporated for feed reliability. Like I said I'm not someone here to say the Glock is all that, I like the other brands listed, but all makes have had their kaBooms. Go back to prior posts and you will find them, there was even a Ruger kaBoom listed.
singleshot
New member
We've missed one point.
The "unsupported" chamber is only part of the story. Not all guns have them and very often some of the barrel ramp is cut away to improve feeding. That is fine as long as it does not extend beyond the "web" of the cartridge case.
If you look at a sectioned case you'll see that the brass at the base is quite thick and it then tapers upward until it reaches basic wall thickness.
Even if some of the case is not supported that's ok as long as the load is not too hot. What has happened with Glocks (and others) is that the ramp is cut so far forward that the thin case wall area is not supported either. That's when you see bulges and possible case rupture.
The "unsupported" chamber is only part of the story. Not all guns have them and very often some of the barrel ramp is cut away to improve feeding. That is fine as long as it does not extend beyond the "web" of the cartridge case.
If you look at a sectioned case you'll see that the brass at the base is quite thick and it then tapers upward until it reaches basic wall thickness.
Even if some of the case is not supported that's ok as long as the load is not too hot. What has happened with Glocks (and others) is that the ramp is cut so far forward that the thin case wall area is not supported either. That's when you see bulges and possible case rupture.
I don't think any body mentioned this, but excuse if I overlooked it...
Re: Unsupported barrels: the SAAMI pressure levels of the different cartridges are WAY different. 45 ACP is about 17,000 PSI, 40 S&W is about 35,000 PSI, IIRC. 9mm and 10mm are similar to 40 S&W pressures. In other words, there is about twice as much load on the unsupported brass in the smaller calibers than the ol' reliable 45. That's why the 45 don't have so many kBs. Even some gussied up 45s (stock ones converted to target pistols) with feed ramps corrected, etc. will kB if fed a hardball or a double charge of Bullseye.
I do not know, but I would guess that there are some double charges out there in reloader land which are responsible for some of those kBs, Glock included.
Also, reloading brass past its useful life. 45 will reload a long, long time; 9mm, 38 Super, 40, 10mm needs to be discarded if it looks suspicious. Don't try to make that dime go too far!
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We don't have a chaplain here, but I don't view that as any major problem... You can rest assured that you will not go in that bag until I've said a few appropriate words over you
R. Lee Ermy as Sgt Major Haffner, from The Siege of Firebase Gloria
[This message has been edited by BigG (edited November 01, 1999).]
Re: Unsupported barrels: the SAAMI pressure levels of the different cartridges are WAY different. 45 ACP is about 17,000 PSI, 40 S&W is about 35,000 PSI, IIRC. 9mm and 10mm are similar to 40 S&W pressures. In other words, there is about twice as much load on the unsupported brass in the smaller calibers than the ol' reliable 45. That's why the 45 don't have so many kBs. Even some gussied up 45s (stock ones converted to target pistols) with feed ramps corrected, etc. will kB if fed a hardball or a double charge of Bullseye.
I do not know, but I would guess that there are some double charges out there in reloader land which are responsible for some of those kBs, Glock included.
Also, reloading brass past its useful life. 45 will reload a long, long time; 9mm, 38 Super, 40, 10mm needs to be discarded if it looks suspicious. Don't try to make that dime go too far!
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We don't have a chaplain here, but I don't view that as any major problem... You can rest assured that you will not go in that bag until I've said a few appropriate words over you
R. Lee Ermy as Sgt Major Haffner, from The Siege of Firebase Gloria
[This message has been edited by BigG (edited November 01, 1999).]
2nd on Bennett Richards' comment. I own a USP40Compact and when you drop a live round into the chamber you see a fully supported chamber; the feed ramp doesn't cut into the chamber at all. I also own a Glock 23. When you drop a live round into the chamber you can see that the feed ramp cuts into the chamber and lacks support at 6 O'Clock. Also a side by side comparison shows the USP chamber walls are thicker than the Glock 23 chamber walls. Nevertheless, I like both guns and try to be careful reloading. I keep batches of shells together and track how many times they've been reloaded and also separate out shells used for hot loads. I also have an aftermarket recoil spring(24 # instead of the standard 18 #) and SS guide rod for the Glock to help the slide go into battery.
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