9mm case failure

What was the results other than a seperated case? Was there any damage to the gun?

I have had the same type of failure in 9mm brass as in your picture, right at the 6 o clock area, the least supported area of the chamber. I have also had a complete failure that left the brass in the chamber while ejecting the base only.
Neither one cause any harm and since I use range brass I have to accept that it's just the way it is because I don't know the complete history of the brass.

Do you know the compete history of the brass you were using.

No double charge as I inspect every round also a double would overflow the case, and it sure got everyones attention.

Click to expand...

Does this mean it sounded like a hot load or just the opposite.

It is very posible that you reloaded a case from a pistol that has a unsupported chamber and when you loaded it into yours it came up at 6:00 in your chamber. Is your chamber unsupported at 6:00 too?

An unsupported chamber allows you to see part of the side of the case whereas a supported chamber fully encloses the sides of the case.

The unsupported part of the chamber is going to be the area of the feed ramp.

Greetings,

Maybe I am wrong. But usually, when you talk about unsupported chamber, you talk about the Glock .40 and .45ACP. The chamber is not "unsupporting" the brass. It is simply oversized a little bit. Each time you shoot, the brass expands a little bit more than in a "supported" chamber.

A guy at the range did a test: He fired 6-7 times the same cases in his glocks 9mm, .40 and .45ACP. The 9mm was ok. The 2 other calibers saw an expansion bulge bigger and bigger each time. He did not dare to do it more than 6 or 7 times because of the stress on the metal brass.

There is a lot of valuable information on the web about the "unsupported" chambers. The CZ75B, along with the S&W models, XD, Ruger, Taurus and many others have tight chambers that support fully the cases in all calibers.

One last thing: the "unsupported" chamber (ok, let's stop calling it that way and let's call it the right way: oversized chamber) in Glocks is the same way than the good old Enfields in .303. Every reloader knows and shoots and reloads Enfields in .303 has its brass quite stressed and you can't shoot as safely the same brass as many times than you can shoot in a Swiss K31 or a Mauser.

Thank you

There can be tight chambers that are partially unsupported, loose and partially unsupported... The two need not go hand in hand.

Here is my Beretta M9's barrel showing its level of case support:



Little better with my P220:



Best yet, and very well supported in my P1:



None of these chambers are what I would consider tight or loose. I also load .303 British, and what I have seen are rifles with poor headspace get separations around the case, not normal up and down cracks that happen from repeated resizing, shooting, repeat. If a 9mm case is sound, it takes a HELL of a lot of pressure to make it burst.

FWIW, cast bullets sized as large as practical, powered by moderate charges of Unique, WW231, and Power Pistol have been the best for me, but for powder puff I will use Bullseye, 700x, etc. I personally do not like to go faster than WW231 with anything approaching service power level loads in 9mm. Add HS-6, AA#5 for service level jacketed loads.

Well, what can I say but sometimes stuff happens?

I've seen brand new virgin WIN white box ammo have a case failure on its first firing- it split open down the side like a zipper. Brass is not manufactured to be reloadable- it just happens that it is- so every now and then one case has some bad metallurgy and it doesn't make the grade.

File this under experience. Glad you weren't hurt.

Heck, I've had a .22LR case fail before. Gets your attention!

Welcome Floyster.

Yes, the part @ 6 o'clock is where cases can bulge out, and if the pressure is excessive/bad case cause a blow-out. While writing this post, I might add a few things about load selection for your CZ75. These pistols have a reletivly short leade (area where rifling tapers into barrel) so many cast bullet loads and some jacketed will need a reletivly short OAL to function. This fact combined with a very fast propellant like Bullseye loaded near it's max Alliant recommended charge weight is something I personally would not do.

I am not saying it is dangerous, just that you will not be afforded any "slack" if something goes wrong (bullet setback), temps get hot, etc... IMO and experience, 9mm 115/124 jacketed bullets work well being driven to service type velocities using propellants of a moderate speed, with Unique, Power Pistol, WSF, HS-6, AA#5, and Silhouette being good sound choices. No, they are not the most economical, but they are much more forgiving than Bullseye. With cast bullets after you find what diameter is best, I have found WW231 and Unique VERY hard to beat. In my case I like a 125 cast driven with 4.2 grains of WW231, and anywhere from 4.2-5 grains of Unique for the same bullet. I have used Bullseye for the same cast bullet using 4 grains to achieve a measured avg velocity of 1092 fps in 70-ish temps. Cast bullets have a lot more variables to crunch, but once you hit on a good load all the work is worth it.

Good luck, have fun, and be safe.

Greetings,

Good pictures Galil. BUt what you are showing is not the Glock "unsupported" subject that anyone talk about.
(all guns that use the modified Browning action have partially supported chambers)

I tried to find the website with the guy having doe many measures of the chambers of the Glock and he demonstrates pretty well the Glock case.

Here are a few of my 9mm barrells:
-Whalther P1
-Taurus 24/7
-Steir M9A1
-S&W 5906
-SIG P225

As you see, they all have an "unsupported" area at 6 o'clock except the Whalter. I do not consider that section unsupported because it is the continuity of the ramp and it is needed for good feeding of the bullet from the mag to the barrel chamber.

I do not have a Glock, so I can't show the difference but I am almost sure there is not. The difference is when you measure the chamber diameter. The GLOCK is quite the same in 9mm than the others. But the chamber is less tight in .40 and .45.

I can say I saw a lot of cases failures in the buckets at the range while I was picking some brass. In order and not a particular caliber:
- Case mouth cracked to less than 1 millimeter
- Case split from the mouth to about the middle
- head separation (VERY VERY VERY rare. I think I saw just 2-3 of those)

I guess I am not following. Perhaps Glock 9mm chambers are large or on the high end of SAAMI specs, and fired cases that expand fully to the chamber walls look swollen all the way around? I think the wrong terms are being used if folks who describe "large" Glock or any other chamber as being unsupported.

Whether there is minimal or a lot of uniform expansion, a portion of the chamber has no support near the ramp, and what I think most will agree is considered the "unsupported" portion. BTW, is that round fully seated in the 225 (P6?) barrel?

Galil,

Yes, the round is fully seated. After your question I became curious and I dissassembled again the gun and pushed hard a round in it.

And no, you are really following and you got it completely with what you are seeing:

- all guns that use the modified Browning action have partially supported chambers. The 6 o'clock needs to be exposed because it is part of the ramp. It is why the Whalter does not have a lack of support at the 6'o clock. it is not a browning design.

- and yes, the Glocks have a bigger chamber. It is why the people who reload for Glock and are serious buy after market barrels.

I wish I would find back that web page where a guy measured the Glock barrels. It would answer all your questons precisely.

Thank you

Kestak,

My Beretta M9, and all 92FS pistols are about as close to the Walther P-38/P1design/as far away from a Browning design as can be done, yet they have very undercut (unsupported) chambers. I have a hunch it was done to improve already excellent reliability considering its nearly straight line feeding, but unless we ask a Beretta engineer we will never know. There is no hard and fast rule on this concerning all Browning style lock-up type pistols and chamber support.

I have read many folks buy conventional land and groove barrels for Glocks in order to "safely" shoot lead bullets. I don't own a Glock, but even with its polygon rifled barrel I have a feeling if good reloading procedure and component selection is followed, no problems would result like any other pistol.

This is my GenIII Glock G23, yes the dreaded .40 cal. itself .







As you can see, the round is FULLY supported and you can't even really find a sliver at the feed ramp anymore as WAS the case in early production barrels. The "unsupported chamber" myth can be put to bed.

As far as the "loose" chamber discussion, if you contact Lone Wolf they have all the exact specs on chamber dimensions and can do whatever you want to your barrel. Most of the posts I've seen where guys cast their own and have an issue with chambering the round, they send it back to LW and they take maybe another 1/000th off the diameter.

Me, I shoot a stock barrel and have for the 1000-1500 reloads I have run through it at all published load ranges in the manuals. I buy once-fired brass at about $40/1000, and plan to shoot it five times and pitch it. I'm not so poor I have to fire every case until it ruptures, and have no intentions of risking a $500 gun, my fingers, and my face to do so.

Glocks rock!

Greetings,

Shibumi, how old is your Glock? I read at a few places that Glock redesigned their barrel a few years ago for the .40 and .45.

--> I am not saying this is the case. This is an unverified information about the redesign. However, a guy at the club who has issues with his Glock and reloading is a 7-8 years old model. He does not cast. He shoots only commercial FMJ bullets.

ALSO: Glock is not a bad weapon. Let's not bash/defend Glock because it can distrqact from the topic.

Thank you

I had the same thing happen to me with the same case. it was a Win. case and probiable loaded with W231. It happen in a CZ champion, in 9mm. it took about 30 minutres to get the gun apart to see what happened and the case blew out at the 6 o'clock in the champer and it blew out threw the rim of the case.
I get the case out, put the gun back together and keep shooting. (it's the price of doing bussiness with range brass.)
That's another reason I don't do plactic guns. There is a picture of a H&K that the case blew up in the chamber and it destroyed the gun. Blew the mag. out the bottom and split the grip. (DId I tell you why I like all metal guns???)
Pat