Glock's unsupported chamber issue.

Gitz

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I was thinking of buying a Glock and did a little asking around as well as some reading. I wanted something as close to my 357 Magnum as possible and was told the model 31, 357 Sig. would do the job however this calibre in a Glock would cause excessive wear to the gun. So then I considered a .40 s&w. I was informed that this was the worst choice of calibre because of the unsupported chamber. I pulled some pictures of off the web and sure enough the .40 had more brass expossed at the 6 o'clock position than did the 357 or 19mm. It also showed pictures of Glocks that had KB'ed. I went on to read that one should not shoot re-loads or commercially reloaded rounds. This was the clincher as I cannot imagine buying factory ammo. That would sure cut dowm on my shooting. Well I guess I'm not so excited about the Glocks now. Any comments would be welcomed.
 
The unsupported chamber is not a problem as many will certainly chime in to tell you.

However I do have a couple pieces of 10mm brass that was fired in a Glock and there is a very significant bulge clearly outlining the unsupported part of the chamber. These were obviously high (above recommended) pressure handloads in Starline cases (primer well flattened and slight flow into firing pin hole). Note that some Starline cases were slightly softer than other brass.
 
I was thinking of buying a Glock and did a little asking around as well as some reading. I wanted something as close to my 357 Magnum as possible and was told the model 31, 357 Sig. would do the job however this calibre in a Glock would cause excessive wear to the gun. So then I considered a .40 s&w. I was informed that this was the worst choice of calibre because of the unsupported chamber. I pulled some pictures of off the web and sure enough the .40 had more brass expossed at the 6 o'clock position than did the 357 or 19mm. It also showed pictures of Glocks that had KB'ed. I went on to read that one should not shoot re-loads or commercially reloaded rounds. This was the clincher as I cannot imagine buying factory ammo. That would sure cut dowm on my shooting. Well I guess I'm not so excited about the Glocks now. Any comments would be welcomed.


Pretty much every firearms maker today tells you that using reloads in their firearm voids the warranty. This is pretty standard... not just a "Glock" issue.

The "unsupported chamber" thing has been talked to death... so have the reported "KB's" on the internet sites. I don't believe that anyone has ever actually proven that (as a % of guns sold and in use) the Glock's are any more likely to experience these kinds of failures than any other similar firearm on the market today. Most of the highly publicized KB's were found to result from the ammunition used or operator's failure to properly maintain the firearm... very few instances of the gun being at fault.

Choose whatever firearm you like but make your choice based on facts... I've seen S&W's, HK's, Glock's and more have these KB failures. Almost ever instance involved re-loaded ammunition, though I've seen "bad" factory ammo as well. There are a lot of Glock handguns out there... the vast majority giving long, effective service to many happy owners... it's pretty hard to argue with success.

Just my personal opinion.

Mark
 
All the .357 SIG is , is a necked down 40S&W, so the excessive wear is crap.:bsFlag:

The 40S&W does have an unsupported chamber, and today, there doesn't appear to be a problem with the gun, UNLESS you overload it.:slap:

As for reloading, I reload for my 17, Pops reloads for his 17 and 35, SteveS reloads for his wife's and his own 17's. You just should use jacketed or plated bullets.:dancingbanana:

Do I like my Glock? Hell yes!:shotgun:
 
Most of the current autoloaders today leave the rear portioin of the brass "unsupported" to some degree, in the interest of excellent feeding properties for the given gun design.

As mentioned above - Glocks work great, being reliable and accurate, are wonderful to shoot and they look "dead ###y". :D

Buy one, (or more) in whatever caliber(s) you like and don't look back! ;)

Jeff/1911.
 
10mm Auto >= .357Magnum

.357Sig < .357Magnum
.40S&W < .357Magnum


You want a 10mm :)

To answer your question about case support, etc. The Glock is perfectly fine... buy ammo and go crazy with it. Do not worry.

The only negative with the Glock is that if you reload, the Glock might stretch the brass more than usual due to the generous chamber size (note I am not talking about case support at the 6 o'clock). You don't need to worry about KB's; you just might not get as much use from your brass (and you wouldn't want to load maximums with brass from the Glock).

New brass... no worries, case support, no worries. Reloading, no worries :)
If you reload and want to get the most out of your brass and push the boundaries of whatever cartridge you are reloading for, get a new barrel. Questar can hook you up with some Storm Lake Barrel goodness.
 
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I have a G22 .40 2000 rounds thru it and never a problem I LOVE IT would recomend it to anyone .357sig is just too expensive to shoot .40 is not too much cheaper but more comon.
 
I just got a(nother) Glock 29 with both 10mm Auto & .40S&W barrel from Storm Lake.

I plan on getting back into reloading, so I've been doing lots of research lately :)

Glocks are awesome...

I've owned to date the following models:
Glock 37 (x2)
Glock 17 (x3)
Glock 22 (x2)
Glock 31 (X1)
Glock 29 (x2)

:p I've never had a problem with any.
 
I reload for my Glock and it, and I love them.
I too was concerned when I first started and also did a pile
of research on the subject finding as much as I could.
I don't load exsesivly juicy, nor do I make powder puffs.
I duplicate the velocities of factory ammo of the same
bullet weight.
If you want to add an extra saftey margin into the mix,
only use ur brass a limited set number of times.
For me, I pitch it after 3 loads. That may sould shy, but I have
no trouble finding more replacment brass, so I'm not to concerned.
I personally know of fellas who load their Glock brass ALOT more
than that.

If you want really hot loads, than yeah, your brass will not last as
long and you will have to keep a tighter eye on it for any adverse
signs of failure.
Happy shoot'n.
 
I was looking at some 9mm brass the other day and noticed the indent made by the typical glock firing pin in the primer was actually protruding! The pressure had bulged the primer!
 
I really don't think the so call unsupport chamber is an issue. Understand Glock been here so many years. Do you think the designer of Glock was having ### while he design the gun. Any design of modern firearms must have their benfit. I don't own one because the ass look but I am going to get one, I like the grip angle so much while not many other guns offer this grip angle except 1911. If you like Glock, go and get one. Many Glock guy love their gun for many reason and you may be one of them.

Trigun
 
fwiw:

i have put well over 10,000-12,000 rounds through my G22, and at least 4000of those have been handloads (FMJ only). I've put plenty of premium defense ammo through it, and whatever else is cheap and available. the gun hasn't blown up. it gets maintained and cleaned when i have the time. i also have a 357sig barrel for it, with perhaps 700-800 rounds launched to date. zero problems. zero malfunctions.
 
I currently own a G21 and G17 and I reload for both. I never exceed the maximum load given for the powder and bullet weight so I don't expect any KB's out of my Glocks unless I really mess up. Rest assured when you buy a Glock as they've proven themselves many times over and know that any firearm can KB under the right circumstances.
 
The unsupported chamber issue arises not with hand loads per se but with reloads, especially where the brass has been reloaded multiple times. Reloaded brass is weaker than its virgin counterpart. When you get a combination of weak brass and poor chamber support, bad things can happen. This is all in theory and I have no idea how weak the brass has to be to reach a dangerous level when shot through a Glock.
 
i must admit to knowing nothing about the Glock.....but why can't you use cast bullets in them. Seems to me that operating costs of that gun are double that of others, and if there is any kind of pressure concern; cast bullets would reduce the pressure level, if all else is equal.
 
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