P-07 KaBoom

[IDescribe]

Forgive my ignorance but what is
"bad case webbing"

If you'll look at the bisected case on the right:



I have seen the case web described two different ways:

• In the picture above, from one side of the case to the other, the thick section of brass that the flash-hole passes through. OR...
• In the picture above, just above the thick brass section the flash-hole passes through, it's the area where the case walls are very thick.

I suspect the first one is correct.  However, this normally comes into play in discussion of incipient casehead separation, where the brass just above the web gets stretched thin during firing and resizing, and eventually blows out, so that whole area tends to get covered in the discussion.  If someone can be more precise on the definition of the web, please add.  I'd love to be sure.

In the case of CZ saying it's bad case webbing, the brass in that area is thicker because no chamber fully supports that area of the case, so it needs a little more strength.  CZ is saying that area was not as strong as it should have been.  Brass cases start out as brass disks, then they get pushed through a die and turned into a brass cup, then the cups get pushed through die after die after die to stretch and shape them into what they are.  CZ is saying that during that process, some or all of the web got stretched too thin and couldn't contain the pressure it needed to contain.

[M1A4ME]

Let me add a couple pictures from my CZ 85 adventure.

When I racked the slide to clear what I thought was a failure to feed this fell out.  It's the rim/base/primer pocket/primer part of the case.  You can see the area, around the outside, where the case metal started to curve upwards to become the side walls of the case.  The rest of the case (sidewalls) was left in the chamber since the extractor only had a grip on the rim (which didn't eject right due to the separation from the case walls).



You can see the case walls still in the chamber.  I removed the barrel and got my finger tips on the brass and pulled it out easily.  Sometimes, stuff happens.  And the only evidence, to my Pre B CZ 85's adventure with high pressure gas being dumped into the interior of the gun, was some extra powder flash marking on the ramp, inside of the frame, etc.  Just dirtier than it would have been for a half magazine of ammo being fired through it.  Can't say what a similar event would have done to my P09 or P07.  I suspect maybe something similar to the one that if featured in this thread.

[armoredman]

Nice save, sir.
I looked at that close up on the case and it looks like it blew right at the beas of the web, as well, but I am no expert of any kind.

[wdbutcher]

Here's a CZ P-09 owner that's had a mishap. It's not nearly as severe, but the frame is still damaged. I checked to see if replacement frames are available, but it doesn't look promising.

*FULL DISCLOSURE*
this gun has a crack in the frame due to a case blowout. The crack in the picture is the only damage to the gun. Slide, barrel, and inner workings are all flawless. I've fired 4 full mags through the gun to test. It's still the same great shooter it always was. You could try to repair the frame to your satisfaction, use it the way it is, or use the slide and barrel for customization.
It will come with box, papers, 2 mags, and everything else it came with new.

[smithrob9999]

WWB is by far the worst 9mm ammunition I've ever used. I'll buy steel cased before that

[SI VIS PACEM PARRABELLUM]

WWB is by far the worst 9mm ammunition I've ever used. I'll buy steel cased before that

There are cases of this happening with many brands including steel. When you are talking about manufacturing millions or possibly billions of rounds of ammo per year this sort of thing can happen.

[Stopsign32v]

WWB is by far the worst 9mm ammunition I've ever used. I'll buy steel cased before that

Care to explain? If you are referring to Winchester White Box then I'd disagree. Not sure what WWB means.

[wdbutcher]

Here's a CZ P-09 owner that's had a mishap. It's not nearly as severe, but the frame is still damaged. I checked to see if replacement frames are available, but it doesn't look promising.

*FULL DISCLOSURE*
this gun has a crack in the frame due to a case blowout. The crack in the picture is the only damage to the gun. Slide, barrel, and inner workings are all flawless. I've fired 4 full mags through the gun to test. It's still the same great shooter it always was. You could try to repair the frame to your satisfaction, use it the way it is, or use the slide and barrel for customization.
It will come with box, papers, 2 mags, and everything else it came with new.

What's interesting about this is that I used to own this P-09. I know the new owner and I knew that he reloaded ammo when I sold it to him. I asked him what happened and he said "It was just a defective case (from glock bulge) reloaded 1 too many times." I really don't know what this means, since I don't reload ammo, but I know that he wasn't using factory ammo.

[SI VIS PACEM PARRABELLUM]

^^^^Cartridge cases are not always fully supported by the chamber and can have a case become weak from being resized multiple times or weakened in the area where it isn't fully supported by the chamber and they can blow out in that area. I've had many 9mm's blow out and revolver cases will split and while it will get your attention it doesn't destroy the gun. I still think the cartridge which blew up the FDE P-07 in the op was either overloaded or the bullet was set back and created a severe over pressure situation.