Decapitated Brass

brass

A reader emailed us with the above photo …

Long time reader here, I went shooting on Saturday and this is what happened to me! I was very baffled. it was Hornady Steel Match .308 FMJ fired out of a CETME. I had a couple of hiccups when I first bought my CETME, but after cleaning it and breaking it in, the gun has been very reliable for the 4 years I have owned and shot it. It probably has 6-700 rounds through it and I can count on 2 hands how many times it has jammed.

It shot fine all day and this happened. Somehow it fired the first bullet, sheared the casing in half cleanly where the neck meets the body, then flung the body of the casing out. Meanwhile the neck stayed in, then it loaded the next bullet and forced it through the neck! I definitely know (and witnessed) the CETME/G3 family of rifles are terrible with brass, but this is just ridiculous. After clearing the jam, the gun ran fine after for the rest of the day.

My question is, have you ever seen this or heard of this happening?

CETME, H&K G3 and other roller-delayed blowback rifles are notorious for wrecking brass cases. I have seen dents and cracks, but never a full decapitation of a neck before. Have any other readers seen this happen in a CETME or G3? I am not sure if that neck was weak, or it somehow (over charged?) expanded further into the fluted chamber than usual and got jammed, or both. At least our reader knows his extractor works!

Edit: I have a very poor memory. Alex wrote an excellent post on this issue earlier this year.




Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.


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  • Jon

    given the unusual nature, and the neck remaining in the chamber i would say the case separated due to a failure of the case, not anything to do with the ejector.

    factory ammo comes out in mass quantity you should expect some minor QA issues. and this certainly seems minor.

  • Whiskey Hammer

    Was it reloaded brass? Off hand, and without running the numbers from a material science point of view, I reckon the case neck was work hardened over a series of feedings, extractions, and neckings, until it was brittle enough to make a clean snap under load. Looking at how even the break is (it isnt the gummy tear you’d expect from soft brass) I’d be willing to bet thats what happened.

    • Jon

      it was steel cased, steel does not work harden.

      • Dave

        Steel certainly does work harden, but it would not be in this case, as no-one reloads steel cases.

        • Vincent peyton

          Thats not true. I know a few people who relod it.

        • http://suburbansdomain.blogspot.com Suburban

          I reload .223 steel cases for function testing. They’re readily available for free and it doesn’t matter if I lose them, or they crack at the neck.

        • Jon

          steel in fact work softens. it gets complicated, but steel does not work harden the way bras does, it tempers through heat/quenching not through work.

  • Ross

    I had the same exact thing happened on my SLR 106f. something is up with the Hornady brass

    • http://suburbansdomain.blogspot.com Suburban

      The story I got was that Hornady was buying primed steel casings from Russia.

    • dale

      I’d check your headspace on that AK. On occasion the headspacing will deviate and create all sorts of atypical issues for AKs not limited to light primer strikes, ruptured cases and general headaches. I agree that hornady brass may be to blame hiwebrr if it is a repeatable issue.

      • Dale

        Hornady* autocorrect strikes again.

  • JesseL

    Looks like a bolt gap/headspace issue to me. The rear of the case is
    trying to move backwards while pressure is still keeping the forward
    portion clamped into the chamber. The chamber flutes are supposed to
    help with that, but I expect there’s only so much they can do.

    For
    what it’s worth, the extractor on any sort of blowback gun doesn’t
    normally extract a fired cartridge. The case is pushed back by the force
    of the combustion gasses (hence “blowback”), and the extractor just
    serves as a pivot for the case when it hits the ejector and to remove
    unfired rounds from the chamber.

  • doc_way

    Such is the problem with steel cased ammo. Looks like pretty standard break due to tensil strength issues. Could be a bad batch of steel used in the case, or par for the course with steel ammo. Run more and find out, or just quit using steel cased ammo all together.

  • Stinky

    Clearly he was shooting too fast. He should slow down, take a breath, and aim a little. That should solve the problem. :)
    / it is a nice clean break, isn’t it. even steel cases should have a bit of tear to them when they fail. kinda points to a material/mfg issue on the case.
    // I dig the new fin stabilized .308 he’s invented, though.

  • Jack

    Didn’t TFB have a post about the same thing several months back?

  • Jonah

    This happened to my Garand once.

  • Matthew Groom

    Steel is far more brittle and far-less malleable in the chamber of a firearm. Also, Steel has a tendency to form tiny fissures which can then cause the iron content in the case to ignite, which can cause a fissure to quickly form into a large split or separation. This is what killed the US 6mm SAW experimental round, and it’s why Russian ammo is loaded light in most cases (except .380, curiously). Thusly, the investment-cast grade of the mild steel used in Russian made ammo cases has to be totally free of even minor imperfections to avoid this from happening. Amazingly, it usually is, but sometimes, it inevitably is not.

    The somewhat violent action of the CETME/G3 series would cause brass necks to stick in the chamber while the rest of the case traveled backwards. This was largely solved by the chamber flutes which allow some gas to travel backwards into the chamber to act as a gaseous lubricant. However, since steel cases do not fully obturate into the chamber to begin with, a larger amount of gasses may enter the system, and the sudden change in the direction of the pressure may cause the steel case to snap. This is just a guess, but that may have been what happened. I would advise against using steel cases in that action (or any action which wasn’t designed for them, really). Also, chrome lined chambers are better for steel cases, I don’t know if your CETME/G3/PTR has chrome lined or not, but that would probably help a bit.

    • EthanP

      I was going to say that it could be the steel cases. They don’t flow the way brass does. Even Russian SVD/Tiger rifles come with a warning to use brass casses.

  • Lance

    Read bad things about imported CETMEs some barrels are not head spaced right so that may be a reason.

  • Dracon1201

    I did the exact same thing with the CETME that I had. The brass was decapitated completely. The next round went in, but did not chamber fully. I, however, had to use a .308 brass extractor to get it out. Funny thing is, when this happens, you can look through the bore, and you wouldn’t notice anything wrong if you didn’t know.

  • iksnilol

    Case was the problem here – steel is brittle compared to brass.

    Also, get a port buffer if you have a roller-delayed blowback gun.

  • Xaun Loc

    Never seen that with NEW brass — looks like a round where the brass has been resized too often.

  • Mr Mxyzptlk

    I always though steel cases were better in delayed blowback actions like this. I am not basing this on any first hand understanding of the physics, but on the fact that the FAMAS kept ripping the necks off of brass cases exactly like on the one shown, so they switched to a steel cased round and this largely solved the problem.

  • gunslinger

    holy cow

  • Bruce

    I’ve had it happen with a cheap AK. Sometimes it happens. There is a reason there are broken case extractors on the market.

  • J.T.

    “the gun has been very reliable for the 4 years I have owned and shot it. It probably has 6-700 rounds through it and I can count on 2 hands how many times it has jammed.”

    2 hands so at least 6. You are looking at around 100 rounds between stoppages, perhaps more. That isn’t reliable, that is actually pretty horrid when it comes to reliability. You said it is a CETME though, which means it is probably a Century build, which explains a lot.

    • Ben M

      That IS a reliable Cetme. I was out with a friend of mine the other day that owns one… FTE or FTF happened more often than the gun going bang. Great design, terrible assembly. The monkeys at CAI couldn’t find their way out of a paper bag, much less build a rifle.

      When I first got my WASR-10, they had installed the safety parts in the wrong order, and the safety did absolutely nothing when activated… ask me how I know… lol. And that is unrelated to the dozen or so other tweaks that gun required to run reliably… and we’re talking about an AK here, not some fancy roller delayed blowback operation.

    • Marcus

      I have between 500 and 700 rounds of dozens of different types of NATO and commercial through my Century CETME, and I can count the number of jams/malfunctions/stoppages on, well… no hands. I’ve yet to have a single issue with mine. It’s an early cast stainless receiver model, and it has run like a champ for the entire two years I’ve owned it. The ONLY issue of any sort I have ever had was with a batch of Santa Barbara 7.62-C with about 50% of the primers not igniting. Ironically, this ammunition was designed specifically for this particular rifle.

      • EthanP

        A lot depends on the ammo. Most problems I’v encountered relate to ammo quality. I’m not saying all bargain ammo is junk. It’s not. But some is. And hand loads can be problematic especially in semi-autos. I have never had function problems with modern brand ammo. I have had a few (very few) problems with Russian commercial ammo in non Soviet calibers.

  • JK

    BTW, the link at the bottom of the article links back to this article, not to Alex’s article.

  • Alex

    I have had it with brass and as mentioned numerous times steel is less malleable

  • Stan Glomb
  • Major Nav

    This can happen when you fire 308WIN in a gun marked 7.62. Even though the rounds have the same external dimensions, the 7.62 has thicker brass and therefore less room for gunpowder. No problem there, but the issue comes from the depth of the chamber in the rifle. Most 7.62 rifles are military spec automatic weapons sold in a semi auto config. Automatic rifles need more shoulder room to prevent jams. Thicker brass will expand to fill the space and most 308WIN cartridges will do just fine, but every once in a while they get over stretched and fail like you see above.

  • Leonidas

    G3 is an obsolete weapon with its operating system. Delayed blowback action is only a joke nowadays. It is not reliable enough in dusty and wet
    conditions. You may think it is a good rifle in shooting range but
    things are very different in mountainous terrain. Even M-16 is reliable
    than a G3 in the field.

  • Toasted Spleen

    The link at the bottom of the article just reloads this article. Thought you would like to know.

  • billrowland

    Looks like the brass wasn’t tempered correctly.

  • motoguzzi

    Steel is fine for the range, for serious social events you should stick with brass.
    I have never had any issues with steel in my HK, but I could not say if it is the rifle or dumb luck. The HK is my only rifle that I will feed steel cased ammo.

  • Kevin Bowers

    I had this happen to me with a 7×57 FN-49. It baffled me as to how it happened, but the FN-49 does like to munch up the brass. Only happened the one time, and has been shooting just fine since. I originally thought it was the old, cheap, mil surp rounds that I have, but maybe not if it happens with quality rounds also.

    • kevin bowers

      oh, and I was using brass cases.

  • Robert

    Yup. My CETME had a case throat stuck in the chamber when I bought it. From what I’ve read, CETME chambers are highly susceptible to fouling and should be periodically checked and cleaned vigorously with an appropriate chamber brush.

  • Dave

    I agree with the previous post but would add that a few thousandths excess headspace caused by either the rifle of the ammo would be very likely to cause the steel case to separate. Some mild steels are fairly ductile but nowhere close to the ductility of brass. I do not use steel cased ammo but if I did I would only use in guns I considered expendable.
    Dave Davison CH Tool & Die

  • Mike

    My PTR91 did this with Match ammo. It ripped the case off further down the body so what looked like a .40 S&W case was ejected.