Overpressure?

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  • d.kaufman

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    Hobart
    So i got a Keltec sub2000 glock 17 version in 9mm and hit the range today. Was using some reloads i got in a 5trade probably 5 years ago roughly from CNC cartridge which according to box is out of Macedonia, IL. Ran 3 full 17 round mags (pmag) and was running a factory glock 30 round mag when on the 29th round i had 1 blow up out the side. Is this an Overpressure/double charge load? Theres also a few other spent cases (3 total) that have a mark on them, 1/3 of a circle mark, that kind of matches the feed ramp. Had zero issues until this 1 blew the side of case out. What say you INGO? I've never had this happen before and it did give me a decent little scare. Anyone hear of this company before? Also have a piece of plastic with the messed up round. I cant visually see where it came from, but haven't done a complete tear down of the weapon yet.

    r7rhwp.jpg


    2hxncat.jpg



    29ookcj.jpg
     

    snapping turtle

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    Could it have fired out of battery? I have seen a few older style pistols fire out of battery and look a bit like that. I don’t know if yours would do it as my time with the sub 2k has been limited.
     

    d.kaufman

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    Could it have fired out of battery? I have seen a few older style pistols fire out of battery and look a bit like that. I don’t know if yours would do it as my time with the sub 2k has been limited.

    I guess it could be possible. Im trying to see where this piece of plastic came from and im thinking it looks look it could be the feed ramp. Primer strike on the round looks normal if that helps to determine the cause. Did feed ramp break because of round blowing up or was timing just right that feed ramp broke just prior to round going off. It was the round was wedged between bolt and throat of the barrel
     

    Fargo

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    In a state of acute Pork-i-docis
    The cases on the bottom left and right of your second picture also appear to be stretched but not to the point of failure. I don't know that I would trust that ammunition.

    Is this a new gun or one that has run fine before?
     

    d.kaufman

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    The cases on the bottom left and right of your second picture also appear to be stretched but not to the point of failure. I don't know that I would trust that ammunition.

    Is this a new gun or one that has run fine before?

    I got it used from a fellow ingoer. First time i shot it. Ran 79 rounds prior to this. Only 1 of these rounds left from these reloads, and i definitely won't be using it. The plastic piece i found is definitely the feed ramp. Not sure if it broke from the explosion or just prior? Looks loke ill be upgrading to the mcarbo stainless steel feed ramp.Heres a better pic of some of the primers
    2lnfupi.jpg
     

    Wolfhound

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    Oh yeah, those primers sure look like over pressure to me. They are expanding back into your firing pin hole on the bolt face. Don't use that stuff. :twocents:
     

    mac45

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    Haven't dealt with them in a while, but I have bought a ton of stuff from CNC in years past before I reloaded one round or another.
    Everything I bought was new ammunition, and as far as I know, they didn't do reloads.
    There's different headstamps in the pic, so obviously these were reloads.
    Wondering if someone just dropped their reloads in a CNC box? I know I've reused 'em. Still have some boxes under my bench in fact.
    Like I said.....it's been quite a few years since I bought anything from them. Possible that they started reloading, but they didn't used to.
     

    d.kaufman

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    Haven't dealt with them in a while, but I have bought a ton of stuff from CNC in years past before I reloaded one round or another.
    Everything I bought was new ammunition, and as far as I know, they didn't do reloads.
    There's different headstamps in the pic, so obviously these were reloads.
    Wondering if someone just dropped their reloads in a CNC box? I know I've reused 'em. Still have some boxes under my bench in fact.
    Like I said.....it's been quite a few years since I bought anything from them. Possible that they started reloading, but they didn't used to.

    I guess it is possible somebody out their own reloads in the box. I got these in a trade roughly 5-6 years ago and figured id burn them up. Now gotta order a feed ramp, so may as well upgrade from the crappy plastic to the mcarbo ss one. I thought the primers looked off to me and thats why i initially thought Overpressure. Only 1 of these rounds left and I'll just go ahead and pull it apart for the case and bullet, probably just the bullet. Doubt id really be able to tell if overcharge since i won't kbow what powder was used
     

    d.kaufman

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    Going thru all the cases i swept up the one that blew up is stamped wcc 1987. Only 1 other 1 stamped that. I had fire some federal ae and winchester thru my Hk p30 and shield 9mm so it is possible the guy i traded with duped me with some of his reloads. Been years ago so i guess i just bite the bullet and never use any reloads other than mine from now on. At least the upgraded feed ramp from mcarbo will only set me back $35
     

    Wolfhound

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    Going thru all the cases i swept up the one that blew up is stamped wcc 1987. Only 1 other 1 stamped that. I had fire some federal ae and winchester thru my Hk p30 and shield 9mm so it is possible the guy i traded with duped me with some of his reloads. Been years ago so i guess i just bite the bullet and never use any reloads other than mine from now on. At least the upgraded feed ramp from mcarbo will only set me back $35

    WCC 1987 would be Winchester Cartridge Company made in 1987. It is the military marking for Winchester brass. In my experience carbines and SMG's handle hot loads much better than handguns. Probably a good thing you were shooting a carbine. Sounds like a cheap fix on that feed ramp. :yesway:
     

    Steel and wood

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    Sure looks like over pressure. The plastic piece is most likely is the feed ramp it just snap in. Mcarbo web site sells metal feed ramps plus a lot of up grades for the sub 2000. I have most upgrades that they offer. There metal feed ramp is a good up grade.
     

    d.kaufman

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    Sure looks like over pressure. The plastic piece is most likely is the feed ramp it just snap in. Mcarbo web site sells metal feed ramps plus a lot of up grades for the sub 2000. I have most upgrades that they offer. There metal feed ramp is a good up grade.

    Yeah. Been on their website looking at all the upgrades. I really didnt mind the trigger at all and the thing shot great up to the point of malfunction. 2" groups at 50' Probably leave the trigger alone but upgrade the plastic trigger guard and obviously the feed ramp since its in 2 pieces now. Im guessing since that piece of brass was military and has thicker case wall maybe thats what could of caused Overpressure/overcharge possibly?
     

    d.kaufman

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    Wolfhound is spot on here.

    I appreciate everyones responses. That was my thought initially, but wanted some more input. I've been reloading a short while and shooting for a long time, and have never had this issue, ever, so i just wanted to be sure. Glad there's no more of this ammo left so i don't have to waste it or tear it down for components. Was looking at the Mcarbo upgrades anyway, guess I'll be doing it sooner rather than later though as its inoperable now. Really love the accuracy out of this thing.
     

    d.kaufman

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    Why I don't shoot reloads from people I don't know.

    Well if you look at the box i posted i thought it was from a company that remanufatures ammo, but i believe what someone stated upthread is true. That maybe this guy just put his own reloads in this box.
    Trust me it'll be my reloads or factory ammo from now on!
     

    Bookmark

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    Not at all disagreeing with the overpressure diagnosis since apparently at least some of them were definitely overcharged, but I usually have flattened primers with that much pressure and from that angle the other case's primers don't appear to be flattened. Could your sub2000 have a particularly large firing pin hole on the bolt face causing the cratering? :dunno: Glad the feed ramp was the only injury....
     

    d.kaufman

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    Not at all disagreeing with the overpressure diagnosis since apparently at least some of them were definitely overcharged, but I usually have flattened primers with that much pressure and from that angle the other case's primers don't appear to be flattened. Could your sub2000 have a particularly large firing pin hole on the bolt face causing the cratering? :dunno: Glad the feed ramp was the only injury....

    When i get some time i will have to look at the bolt face. Oldest daughter showed up with the grandson, so had to put it away for now.
     

    bigedp51

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    It could also been caused by old weak brass fired too many times. I'm sure you heard of "Glocked Brass" but any barrel that does not fully support the base of case can bulge when fired.

    And when a bulged case is resized it will weaken that part of the case and the weakened part of the case can let go.

    I buy bulk once fired 9mm WCC cases and have never had a problem. "BUT" I also use range pickup brass and only use light practice loads in them.

    I'm 67 and have been reloading for over 47 years and last month I had my first double charge in a pistol case. Luckily it was in a Ruger .357 Vaquero and the cylinder is thicker in that caliber. I think I know what happened, normally I charge all the cases with powder leaving them in my loading block and check them all with a flashlight before placing the bullet in the case. But I bought a new RCBS Charge Master and was loading one case at a time with powder and then seating a bullet and somehow double charged the case. I was lucky and was loading light Cowboy loads of 231 and not loading hot.

    Lesson learned, back to the old method of visually checking all the cases in the loading block for the same level of powder before seating any bullets.

    Bottom line, I would never shoot anyone else's reloads in my firearms, and "anyone" can make a mistake when reloading.
     
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