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Thread: EARLY signs of over-worked cases?

  1. #1
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    Default EARLY signs of over-worked cases?

    On another thread Professor Murphy talked about the Lee Factory Crimping Die, emphasizing that the beneficial features of the die may also result in over-work of the case. Since I use the LFCD for many calibers (454 Casull, .45 ACP, 10mm, and .223) his comment caught my eye, and I realized that I may not be up to speed at spotting EARLY signs of metal fatigue.

    I understand cracks on the case mouth, shoulder or case head separation...that's time to toss. However, what about EARLY signs that the brass is becoming worn from over-work by the die? How can I tell? Is it a visual discoloration or shininess at those same failure points? Lost Sheep talked about running his finger over the case mouth...are you feeling a crack that you can not yet see? Do I get to buy another new gizzmo that will measure early fatique?

    Thanks in advance guys...

    Doc

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    Default

    In my experience with .45 ACP and the Factory Crimp die, it's low enough pressure that I load them until I see cracks, then toss. I have literally bucketfuls of .45 auto brass, so it's just not worth it to me to try to do exotic stuff to prevent it from happening.

    However, I've never used the FCD with roll-crimp rounds (.454 casull), or bottle-neck rifle cartridges, so I'm not sure what it does to the brass there. My guess is that you're not going to see any warning signs before a case mouth cracks due to work-hardening of the brass. What I hear people doing is annealing the case mouths after X number of firings (and I don't know what number 'X' might be). Never tried that myself though.

    I don't know of any visible warning signs whatsoever that might give you a heads-up that the brass is about to fail, but also afford you an opportunity to save the brass. Some people might consider a bright ring just above the case web, which is a sign of incipient case head separation, a warning sign--I consider it a failure because by the time it shows up the brass should be pitched, there's no way to salvage it.

    Mike

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    Default When to anneal?

    Quote Originally Posted by MikeT View Post
    (trincated for brevity)
    My guess is that you're not going to see any warning signs before a case mouth cracks ...
    If you have a lot of 25 cases, shoot them as a batch until one shows signs of failure. Toss that one and anneal the rest.

    Lots of trouble? Trouble is my nickname.

    Lost Sheep

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    Default

    Thanks for taking the time to post the information and suggestions guys. I appreciate it.

    Doc

  5. #5
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    Doc,

    For straight walled cases, carefully look the cases over after the expanding operation. When the case mouth is flared it will show any splits that are beginning to start. Taper crimped cases last forever it is those we flare out them severely roll crimp that seem to split after a half dozen loads. The belted cases seem to get a ridge just in front of the belt this can prevent chambering. Rimless bottle necked cases will usually begin to get loose primer pockets before they split at the mouth unless very moderate loads are used then just trimming will save most of those.
    Is there nothing so sacred on this earth that you aren't willing to kill or die for?



  6. #6
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    Thanks professor...very informative and exactly what I needed.

    Doc

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