Source of Horizontal Gashes on spent 9mm cases?

Discussion in 'Handloading and Reloading' started by Harriw, Apr 20, 2021.

  1. Harriw

    Harriw Member

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    Hey folks,

    Anybody ever seen horizontal cuts on 9mm brass like this before? There's almost always a corresponding dent on the case a little higher up towards the mouth, a little further around the case to the right (the dent looks similar to the dent you get in .223 cases from an AR's case deflector. But the location of this dent relative to the scratch varies a bit. You can see the dent well on the 1st, 3rd, and 4th cases from the left). This is range pick-up, not my brass. But I see these regularly. They drive me nuts because who-ever is shooting these likes to shoot Federal, which is my head-stamp of choice (FC). It gets frustrating having to cull 1/4 to 1/3 of the scavenged brass I find in my favorite headstamp, lol (I often don't notice it until after I've cleaned up the cases, or I wouldn't pick them up in the first place). I'm just curious what this might be caused by. Is this common with 9mm AR's or something like that? It looks ejection-related to me, but I'm no expert.

    Thanks!

    20210420_113343.jpg 20210420_113357.jpg 20210420_113400.jpg 20210420_113402.jpg 20210420_113405.jpg 20210420_113411.jpg
     
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  2. bullseye308

    bullseye308 Member

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    Looks like the ejected casings hit something on the way out. Do you know what they were fired out of?
     
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  3. NMexJim

    NMexJim Member

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    Some pistol manufacturers - Sig, Glock - don't worry about your reloading brass looking too pretty when it hits the ground (they do worry about reliable ejection), but there are more dents on these cases than I've seen before. It'd be interesting to know what they came out of.

    I'd size 'em and shoot 'em. They'll iron out.
     
  4. Kaldor

    Kaldor Member

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    Same here. Theyll be fine
     
  5. Harriw

    Harriw Member

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    No idea what they were shot out of - was hoping somebody here would recognize them. The dents I'd use without a second thought. But the horizontal scratches are deeper than I'm comfortable using - particularly given that they're about where the bullet will seat (The pictures make them look a bit like simple dents, but those horizontal lines right where the bullet would seat to are deep gouges/scratches. They're deep enough to feel your fingernail drop into the crack). Additional stretching of the brass in an area that's already compromised.... It's entirely possible I'm being overly cautious, but I figure reloading isn't the place to take risks. Too bad, as this is my favorite headstamp and I'm running rather low on that one after loading up 1k rounds of it for upcoming months.
     
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  6. Milt1

    Milt1 Member

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    My take is whatever is happening is happening at the same time given the proximity of the "cut" to the dent at the top.
     
  7. PO2Hammer

    PO2Hammer Member

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    Those look like rounds that were at the top of the magazine when the slide short stroked.
    With light loads sometimes the slide doesn't get behind the rim and hits the side of the top round in the mag.
     
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  8. Harriw

    Harriw Member

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    I agree. The dent and scratch are the same distance from each other in the axial direction. their location around the circumference changes a bit though, almost as if the case is spinning at varying rates when one or the other occurs.

    It's possible... but I see a LOT of these. From my last trip, I kept ~60 good FC cases, and tossed 20+ more due to this defect. The ones I kept included many that do exhibit this same artifact, but the scratches were shallow enough that I kept them. When I notice these at the range, they're all grouped together. No surprise, since they obviously came from the same gun. I've seen cases like this many times over the past year or 2, in similar quantities. Based on the piles of these I've found in the dirt (and a lack of FC cases NOT showing this defect mixed into the same piles), I'm fairly comfortable saying this is happening on every round from whatever firearm this is.

    Re-reading your post though, I realized you didn't mean *just* the top round in a freshly-loaded magazine. With that in mind, you could be right - I have no way of knowing if these were from reloads of factory loads. Although I sort my headstamps such that my reload batches are all of the same headstamp, I assume most people aren't that OCD. My assumption (perhaps an incorrect one) was that piles of like-headstamp were likely factory loads.
     
  9. BreechFace

    BreechFace Member

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    Hitting the ejection port, would be my thoughts.

    Looks like the ejection port needs to be enlarged or tuning of the buffer springs.
     
    Last edited: Apr 21, 2021
  10. shoobe01

    shoobe01 Member

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    Here's a nice video of how messy ejection can be:

    Both are probably ejector port, the dent is first, high speed, and something relatively rounded, the second a sharper part it smacks as a result, but semi-lightly.

    Could easily be a handgun, have seen everything (1911, Glock, XD, CZ...) cause dented cases on ejection.
     
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  11. Otto

    Otto Member

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    Just mark your brass with a Sharpie to easily identify it from others. It’s not that difficult.
     
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  12. Harriw

    Harriw Member

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    I actually do mark my primers with a sharpie for easy identification. More to mark them as "once/twice/etc. reloaded" than as "mine" though. There aren't typically that many shooters at a time at my club so identifying your own is rarely a problem. This is somebody else's discarded brass I'm picking up for use. It was obviously not wanted, as I was the only one at the range at the time (meaning somebody got in their car and left it there in the gravel).

    I freely admit I'm being "picky beggar" and complaining about the condition of the free brass I find lying around and make no claims otherwise. More than anything else though I was simply curious what might cause those markings, as I see them often enough that I don't believe them to be caused by stove-pipes or other malfunctions.

    It could certainly be hitting the ejection port (or something else) similar to that. Actually that's rather likely... If I'm finding this in the gravel, it means that it was ejecting forward across the firing line at least to a certain extent. I suppose it could also mean that the shooter gathered up his casings and tossed them across the line, but that's doubtful... Our club has collection barrels for unwanted brass that can be easily swept up behind the firing line.
     
  13. ballman6711

    ballman6711 Member

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    I haven't seen it on 9mm cases, but I do have a 1911 45acp that left those same type of marks.

    IMG_3453.JPG IMG_3456.JPG IMG_3463.JPG

    In my case the loaded rounds were hitting the barrel hood while chambering. I had no corresponding dents as shown in your pics. My fix was twofold, first I broke the edge on the barrel hood which helped but didn't completely fix the problem. Second was to adjust my coal, which eliminated the problem. I would think the dents would be happening during ejection when the brass hits the ejection port.

    chris
     
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  14. Klaatu Barada Nikto
    • Contributing Member

    Klaatu Barada Nikto Contributing Member

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    I see this often with 223/5.56 brass. The ejector is trying to toss the case before it has fully cleared the port.
    Just about every bolt parts kit that I have ever purchased came with an extractor "O" ring.
    It positions on top of the extractor spring and slows down the ejection process. Not much, maybe 1k\sec. But it's enough to eject cleanly.
    My guess is right there with yours, I believe it's a 9mm AR that's the culprit.
     
  15. whughett

    whughett Member

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    I have a PCC carbine in 9 that will throw the cases a county mile compared to the same rounds fired in in a pistol.
    My guess is someone is shooting them in a PCC.
    Maybe someone with a good stash of 9MM. :(
     
  16. lordpaxman

    lordpaxman Member

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    Have you run any though your process? Dents like these typically either size out or fire out. I’ll cull splits but that’s about it. Good luck.
     
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  17. EricBu

    EricBu Member

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    My Scorpion Evo makes similar dents. I ignore them. They'll size fine. Send 'em.
     
  18. Jim Watson

    Jim Watson Member

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    The horizontal dents look like "stem bind" at the chamber mouth, the mouth dents likely upon ejection.
    Cases are usable by MY standard.
     
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  19. PO2Hammer

    PO2Hammer Member

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    disregard
     
  20. MFInc

    MFInc Member

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    I recently shot some 40s+w rounds with 2 diff measures of WSF using SPM primers out of a glock23., the higher loads left a similar mark on the cases. Just not as exaggerated. Never had any other ammo leave a mark like that. I'll try to get pics of them.
     
  21. DocRock

    DocRock Member

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    Ejection port dings. Why we have sizing dies...
     
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