CZ97B Barrel Failure, Metal Fatigue or Crack?

[Peter M. Eick]

Ok, this occured at round 3243 out of my 97b. It is definately used and reliable gun. Ammunition was PMC 230 grn hardball. The springs are changed routinely, last changed out round 2724. The gun had been fired already 50 times and was into the second box of ammo (today). The sequence of events went something like fire, and jammed. Slide locked part way back. Dropped the magazine, and tried to break it apart. No luck. Finally at home I used a rubber mallet and tapped the slide forward enough to pull the slide stop and get it apart. Now to the pictures.

The last picture is for anyone who thinks this was caused by an overload. I would have expected that given an overload the slide stop would break. The cartraige by the way appears perfectly fine with no problems, no flattening of the primer or anything. Since it seems fine I figured I would not post a picture of it and focus on the break point.

I interpret (and remember I am Geophysicists not a Metalurgist) that we are seeing metal fatigue or an incipent crack in the barrel. The metal looks a bit crystalized to me, but again I am guessing. In particular I see the shiny metal around the 4 sides where it broke, yet the center all appears to be more mottled and grainy. I would have expected that if the part completely sheared on a new failure plane it would be shiny everywhere and NOT just on the outside edges. Hence, my guess that this was an incipent failure or crack in the barrel.

Comment on the colors on the screen. The shiny parts actually look like fresh metal. The core of the broken parts apears to be a dull metalic color, like a soft gun metal grey. The core is not shiny or appears to be freshly broken.

Any thoughts suggestions or comments? I figure I will email the pictures to CZ on sunday and ask for a new barrel. I want to keep the old one because it has my serial number on it, but I doubt they would let me have it.

Do you think it is unreasonable to ask CZ to serial number the barrel to my gun?
Do you think the gun needs to go back to CA to have the barrel refit?

 

[Wildalaska]

I find it hard to beleive, according to what I read here...CZs never break....

PS send it back to CZ and have the barrel installed and renumbered

WildthengetacoltAlaska

 

[mete]

Crystallized ? Metals are always crystalline.The fracture surface seems quite dark .The photos are not clear enough to come to a good conclusion.The shiney metal has been smeared when you hammered off the barrel .As a metallurgist [note proper spelling !] I could take a close look with some magnification if you want to send the broken off piece to me.

 

[Peter M. Eick]

Mete.
Sorry about misspelling metallurgist (mea culpa!) and thanks for the comments. The fracture surfaces are pretty dark, that is why I tried to verbally describe the color to you. I think actually the metal was smeared and went shiny when it slid over the top of the slide stop. Does the dark color mean anything? I mean it is a gun metal grey, not black or anything.

I may take you up on your offer to look at the broken part under a microscope, but I figured I should at least give CZ an opportunity to let me know if they want both parts or what. I take it that you would need a more magnified view of the break point? Like what sort of zoom? I may be able to get it under a petrographic microscope at the office on monday and get some pictures.


Wild. Thanks for the comments. I think that is what I will do after I ask for them to handle it as a warrantee item. I figured I would ask them to pay for the shipping before I offered to do it. Also I see in your tag line that I should "then get a Colt". Sorry my little COLT diamondback is back at Colt getting the bolt screw fixed right now. Otherwise I would have been shooting a Colt.

 

[mete]

Peter, it should be magnified maybe up to 10x ,but sharp focus [ hard to do since the higher the magnification the shorter depth of field].You also have to play with side lighting to see the texture .A bit hard to explain in words.The fracture surface color should be light grey.There are other things about that fracture surface that are confusing.

 

[HSMITH]

The pictures are hard to see much in but what I see looks like a bad heat treatment or a forging that was too cold. The grain structure should be longer than what it looks like in the pictures.

Just a guess, hard to see enough in the pictures to tell much.

 

[Black Snowman]

As an amateur, I'd say get the factory to fix it. Looks like a mfg defect to me. If you don't trust the gun after that, I'd be willing to buy it from you.

 

[armoredman]

Definately get a hold of Mike Eagleshield at CZ-USA [email protected] and let him know what happened. That is unacceptable, especially if all you used was factory ammo, and CZ-USA should make that right for you. Then shoot the heck out of the new barrel, and disregard MrIignoreanyonewhodisagreeswithme. He hates CZs for some odd reason. And, as a former range officer at two differant ranges, I HAVE seen more Colts fail than CZs. Everyone makes a lemon every so often.

 

[BryanP]

and disregard MrIignoreanyonewhodisagreeswithme. He hates CZs for some odd reason. And, as a former range officer at two differant ranges, I HAVE seen more Colts fail than CZs. Everyone makes a lemon every so often.

Armoredman, I don't suppose it might be that on average you've seen a 100:1 ratio of Colt to CZ at your range. I'm no statistician, but that might have something to do with you seeing more Colts fail than CZs.

Just a theory, mind you.

Bryan (who has nothing against either Colt or CZ and doesn't own either at the moment)

 

[armoredman]

I wouldn't call it 100:1, but not to far off, not counting the rental CZ we did have, before someone stole it. The longest lasting pistols we had were the Rugers and Glocks, with the CZ thrown in until it went bye bye. The worst, in order worst to not too bad, were the HK USPs, SiG P230, Taurus 92, and Springfield 1911s.
We had a few problem with the two Colts we had, but nothing to write home about.
On the range itself, we did have quite a few CZ shooters, but Colts primarily in the matches, and they failed quite often, (note - these were all "tricked out, worked on" etc, not stock 1911A1s), memorably one Series 80 that shot its front sight clear down to the bullet trap.
My point was every maker makes a bad gun once in a while, but my experiance with several CZ manufactured pistols has been excellent. Just as some people have good CETMEs, but the one I had was (censored).

 

[Peter M. Eick]

Email is sent with pictures to Mike at CZ. I will call him tomorrow and try to get some 10x pictures under the petro-microscope.

It is interesting now that I have slept on it to think about how many rounds I have fired and then it finally let go. Kind of made me look over my carry gun a bit today. You just never know when something like this is going to happen even on a gun that has over 3200 rnds down it. I would have called that gun in principal "broken in".

Thanks again and I will keep you all informed about what mike says.

 

[P95Carry]

Like Mete I'd like a higher mag pic .. plus the color is a bit distracting. I'd think probably a stress crack began some while ago and this has been a brittle fracture ... suggesting the original heat treatment was inaccurate. hard to tell if any inclusions from the pics .. but one area does give me reason to want to see closer detail.

In fact Peter all you need post is just the cropped parts, of the trouble spot. And .. maybe daylight shoot for another pic perhaps or - tweak the white balance.

 

[stans]

My first thought is incorrect heat treatment in which the metal is actually too hard and becomes brittle. This sometimes happens, Springfield Armory had a batch of slides that were too hard and they had a lot of warranty returns for cracked slides.

 

[Peter M. Eick]

It is kind of overcast today, but I will get a true color set of pictures out later this morning.

Thanks again and I will call Mike at CZ in a few hours.

 

[mete]

3000 rounds is not a lot of rounds.

 

[Peter M. Eick]

That was my attitude. 3000 and it was just starting to "feel" right in the hand and get broke in.

I talked to "Mike" at CZ. He was very pleasant, somewhat appologetic (sp?) and asked me to send it all it. He thought from the pictures that it was a bad part and probably an incipent fracture or the like. He said based upon the pictures it would be a warantee item, but we shall see. As an end user, I figure that is all I can ask for.

While he has the gun, I figured since he has a good reputation over on the CZ-forum that I would have him do an SA/DA trigger job and put some adjustable sights on it. I also asked him to look at the ejection pattern. I hate guns that throw the brass inconsistently.

Ok, off to FED-EX. Update when he calls.