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.308 Brass - Impending Case Head Seperation? Pic inside...

Discussion in 'Handloading and Reloading' started by PowderMonkey, Mar 26, 2012.

  1. PowderMonkey

    PowderMonkey Well-Known Member

    Hey folks. My last trip to the LGS I purchased a rubbermaid tub of 250 'used' .308 WIN brass for $24.

    About 30% of the used brass looks like those shown below. I have already culled them aside. I tried the paper clip trick on them and could not feel a ridge or anything inside at that depth that 'caught' the paperclip - but like I said I've already culled the brass that looks like this - as my face and my high-dollar Armalite are too valuable to me to risk on a $0.10 piece of brass.

    All the rifle brass I've ever loaded has been from new ammo that I fired, or factory bagged new rifle brass. None of my brass has had more than about 4 loadings on it, and I'm loading fairly light (70-80% of book max) so I have never seen anything like this in person.

    Am I seeing what I think I am seeing? Impending case head seperation? Should I crush the shoulder and neck closed and put them in my recycle bucket? Did someone sell me 50% wore out used brass and 50% probably almost wore out brass... : (

  2. blarby

    blarby Well-Known Member

    There is something seriously wrong with that.

    May be case head sep, may be something else.

    If you aren't familiar with the paperclip trick, it can be tricky to use... can you section one ?

    IMO, without better pics, i'd say thats is indeed soon to be CHS, and wouldn't load them.
  3. FROGO207

    FROGO207 Well-Known Member

    Cut a couple of them in half lengthwise and look for separation if you want to be sure. The marks look like where the links rubbed on the brass when it was pulled out of them. The brass was probably linked together for use in a machine gun and someone pulled the brass out of them and loaded it in a standard firearm to fire. Case head separation will be a wider band of brightly colored brass that has a frosty appearance. All of mine were at least 1/16 inch wide. Those are scratches on the outside.
  4. blarby

    blarby Well-Known Member

    Also possible.

    I can see a little banding now........ better pics would help.
  5. gamestalker

    gamestalker member

    I noticed in the pics that #1 and #4 of those cases have what appears to be identical bands, at identical angles that bend down toward the web. It almost looks like the bands are showing a casting of a chamber defect, or somthing is in the chamber. But the brass looks quite different than what I'm used to seeing when my brass begins to separate. I shoot all my brass right ot the last loading so I am very familar with the initial signs, and the extended signs of separation.

    If your taking good care to maintain the shoulders, you should be able to get 9 or 10 reloadings from your brass. I don't load for the .308, but I do load 06, .270 win, 7mm RM, and few others, and even though I run large charges of slow burning powders, I still manage to get 12-15 reloadings before they start the process of separation.
  6. earplug

    earplug Well-Known Member

    Slice them length wise

    When I was a master gunner with a bunch of M60's that had head space problems. Many cases looked like your photo.
    We were having lots of separated cases stuck in chambers.
  7. evan price

    evan price Well-Known Member

    To me, they look like the rifle they were fired in had a chamber that had a chatter mark in it.
    I would take the worst looking one and hacksaw in half lengthwise and check the brass thicknesses. That would tell 100% for sure if there is anything to worry about.
    If your paperclip test didn't feel a groove there may not be a groove. I've seen some M1 brass that had a line in it but it was fine.
  8. P-32

    P-32 Well-Known Member

    I've seen this before on F/L sized brass. There is no problem as long as there is not a corresponding ring inside the case.
  9. scythefwd

    scythefwd Well-Known Member

    is the ring raised? It almost looks to be in the 3rd casing. If that's the case.. chamber inperfection. If not... if the peperclip don't feel the dip.. I'd use it.
  10. bigedp51

    bigedp51 member

    Your marks are from the inside of your chamber as explained above and are raised bumps and imprints of your chamber, below are what case head separations look like on a .308 cartridge.

  11. gamestalker

    gamestalker member

    +1 Bigedp51 !! Those are some really good examples of the common place, and common appearance of case head separations. If that were my rifle, I would take it to a good smith and have the chamber examined and head space checked. That brass just isn't looking consistent with case head separation the result of normal wear and tear.
  12. snuffy

    snuffy Well-Known Member

    Those don't look like incipient case head separation. But DO look like they were fired in a rough chamber.
  13. PowderMonkey

    PowderMonkey Well-Known Member

    None of this brass has been fired by me - I bought it used at a LGS.

    Anyway I decided to fire up the scroll saw last night and do a little destructive testing. Pic with a real camera with macro mode now, as opposed to my initial camera phone pics. You can even see my pointy paper clip scrapes inside on pic #3. : )

    Yes the ridge is raised but barely. One is not worse than the other - on the brass that have the mark, it's all the same.




    I can see no ridge or thinning of the case walls in the area around the ring. I'm assuming these are just fine and it was a rough chamber as many of you have suggested. I bet with a firing or two and subsequent full length resizing (all my 308 runs in both AR-10 & bolt guns) the marks may get ironed out and almost go away.

    Thanks for all the replies!
  14. PowderMonkey

    PowderMonkey Well-Known Member

    They all have that angled piece that veers off down towards the web. I just didn't have them all rotated to the same angle.

    I'm totally settled now on - like you said - a casting of someone else's chamber defect.

    Last edited: Mar 28, 2012
  15. Clark

    Clark Well-Known Member

    Looks like the OP's smith did not brush all the chips off the reamer.

    I chambered a 257RAI .004" too long. If I try to fire form in one step, I will always get separation at the shoulder from stretch.

    Attached Files:

    Last edited: Mar 28, 2012
  16. Walkalong

    Walkalong Moderator

    Very good pics PowderMonkey. There is obviously no problem with that brass, other than the cosmetic issue, which won't hurt anything.
  17. fguffey

    fguffey Well-Known Member

    Clark, I am sure everyone else believes a chamber that is longer from the bolt face to the shoulder .004” will result in a separation just behind the case body/shoulder juncture, I don’t. Do not take it personal, it is a matter of keeping up with more than one thought at a time, measuring the case length before and again after (from the head of the case to its shoulder) and being able to measure the length of the chamber first.

    Then there is that part where the model and design of the receiver information is omitted, and, it helps if the fire former has a very good understanding of what is happens when a case is formed when fired, 5 different chambers can be chambered with identical dimensions in different receivers and produce different results.

    I did ask, do not to take this personal.

    F. Guffey
  18. Walkalong

    Walkalong Moderator

    I read that as .004 over accepted headspace, which would be more than .004 stretching. Perhaps I am wrong.
  19. Clark

    Clark Well-Known Member

    I chambered that 257RAI in 2002, nearly my first rifle I chambered.
    I used a 257R piece of brass for a go gauge.
    I did not know the the firing pin would crush Roberts brass into the Ackley chamber neck base, and then the case would get stretched.
    All my brass get stretched in the same place.

    What I learned to do [and I tried a lot of stuff] was 10 gr of any pistol powder, back fill with Cream of Wheat, no bullet and if forms half a shoulder that will stand up to the firing pin on the next shot. The next shot is full powder, full accuracy, and makes a full shoulder when done.
  20. PowderMonkey

    PowderMonkey Well-Known Member

    Thread drift! :neener:

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