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Discoloration on factory 9mm casings

Discussion in 'Caliber Corner' started by catalyst686, Sep 21, 2010.

  1. catalyst686


    Apr 13, 2010
    Ok, I don't have an incredible amount of knowledge with ammunition asides from the basics. I was loading my mags and I noticed strange shaped, dark marks all over the majority of the casings. I am using Speer law man 9mm 115gr. TMJ rounds. This is pretty hard to explain so I am going to have pictures to do that for me. My main question is, obviously, what are these marks? why have I never see these types of marks on ANY other of the many brands of ammunition I have used. The only difference I can take into account is that these rounds are TMJ, not the usual FMJ. Could they be treated with something different, which would naturally cause these marks? I really have no idea, I'm guessing they are safe to shoot, but I obviously would want to be sure before I go to the range tmrw afternoon. I've posted pics of the marks on the casings, all I have is my 8 meg camera phone, but I think the marks I am talking about can be seem fairly easily.
    Thanks for the help all, I really appreciate it, if someone wants additional pictures of anything that would help them in figuring out what it is, I would be more than happy to take a few more pictures and put them on here. Here are a few bullets where i thought these "marks" could be seen the best. The marks are somewhat resistant to light, which makes them harder to see, so the bullets you will observe you will see "some" of the marks, keep in mind that there are actually many more all over case, its just hard to see them because of the lighting.
    Note: I'm guessing there will be quit a few fellows suggesting that the ammo had been loaded in mags many times, of they have cycled through the weapon without being fired. These bullets are STRAIGHT out of the box, 3 of them were loaded in a mag, I left those ones out of the pictures.
    again, thanks to all the knowledgable GT's out there that have been able to help me with all of my newb "issues" LOL.

    Last edited: Sep 21, 2010
  2. robin303

    robin303 Helicopter Nut

    Sep 27, 2009
    Austin, TX
    Go to the reloading forum and ask the guys there.

  3. Dreamaster


    Feb 9, 2009
    Outer Space
    Wow this place just isn't what it used to be. :crying:
  4. fredj338


    Dec 22, 2004
    It looks like corrosion, but the pics aren't that good. Probably from storage or handling during packaging.
  5. bentbiker

    bentbiker NRA Member

    Sep 11, 2009
    Orange County, CA
    As for your pictures, you are trying to take pictures closer than the minimum focusing distance for your camera. If you notice, the cartridges in the background are in perfect focus. With an 8MP camera, you can enlarge a well focused picture taken another 6 inches from the camera. As to what I assume is corrosion, do they cycle OK? If so, and you only have a box or 2, since they are presumably for the range, I'd say shoot them and forget about it.
  6. Merkavaboy

    Merkavaboy Code-7A KUZ769

    Catalyst686, there's nothing to worry about, all it is is tarnish on the brass. I've seen this type of tarnish on many brands of ammo, but I've seen it most often on Speer brass. I have no idea what causes it though. My guess is it's probably something like "water spots" caused by not being completely dried off after the cases are washed/cleaned during the mfg process.
  7. Roering

    Roering Sorting nuts

    Feb 14, 2008
    Costa Mesa
    I see it on factory ammo all the time. It will shoot just fine.

    But if you still have reservations, you could mail it to me.
    Last edited: Sep 22, 2010
  8. Zombie Steve

    Zombie Steve Decap Pin Killa

    May 31, 2007
    Old Colorado City
    Ammo Pox. :supergrin:

    Where's Tous when you need the "casing - what sausage goes into" rant?

    Just some form of tarnish. Go shoot them and you'll feel better.
  9. catalyst686


    Apr 13, 2010
    Thanks for the info, I shot 300 rounds of it at the range today and I had no problems. I wont be worrying about these marks on Lawman ammo anymore.