Safe to shoot?

Discussion in 'Reloading' started by Morack, Feb 21, 2014.

  1. Morack

    Morack Well-Known Member

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    I've got an Olympic Arms UMAR AR-15 chambered in 22.250. While resizing brass I failed to realize my die was set up incorrectly and set the shoulder back to 1.567 instead of saami min 1.571.
    Before I noticed my error I had fired 15 of these rounds with no problems.
    Would they be safe to shoot? Or would headspace be an issue?
    Thanks in advance!
     
  2. varmintH8R

    varmintH8R Well-Known Member

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    What is the headspace measurement of your fired brass?

    I would strongly suspect that 4thou under spec will not be an issue. Check the 15 you fired for a shiny line on the brass just forward of the case head. Also make a small 90deg "hook" on the end of a paper clip and run it inside to feel for the beginning of thinning in the same area. If there is no evidence of issues using these indicators, I would say you are GTG - not just to fire them but to reload them again as well.
     
  3. Morack

    Morack Well-Known Member

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    Fired brass measures 1.588. I will check for line tomorrow and try paperclip at 90.
    Thanks
     
  4. varmintH8R

    varmintH8R Well-Known Member

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    The fact that it is an auto-loader makes this a more interesting question. By sizing to SAAMI min you are still pushing your shoulder back 17thou. When you fire the round, the case stretches back to chamber dimensions. Doing that over and over is likely to be an issue. At minimum it will greatly reduce brass life.

    Because it is an auto loader, you have to size your brass enough to ensure reliable feeding. That means not just pushing the shoulder back but also making sure you size the case far enough down toward the bottom. I would guess that 15 thou difference wouldn't make a difference in that regard, but the proof is in the pudding.

    I would recommend setting your sizing die up to push the shoulder back to about 1.584 (4thou of shoulder set-back vs fired loads). Load 5 rounds like this, and shoot to see if there are cycling issues. If not, I would use this as your "spec" for future sizing. If there are feeding issues, work incrementally toward the SAAMI spec until you find the place with the least amount of sizing but 100% reliability in chambering.

    The less you work the brass the better, but with an auto-loader you also have to factor in reliability and chambering. On my bolt guns, I usually bump shoulders 1thou. On my 223 auto-loaders, 4 thou I has worked for me.

    Good luck with yours and let us know where you end up.

    Brandon
     
  5. Morack

    Morack Well-Known Member

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    I tried the paperclip with didn't notice any thinning or shiny ring above case head. I will try setting die @ 4thou.

    Thank you for your input it is appreciated, Marc
     
  6. varmintH8R

    varmintH8R Well-Known Member

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    No problem, hope it helps. 22-250 in an AR type platform sounds pretty awesome. I am going to look it up to get the specs. Let us know how it shoots, and post a pic of the rifle if you have one.


    Brandon
     
  7. Morack

    Morack Well-Known Member

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    It shoots consistent 3/8 @ 100. Great big country coyote gun.
    Thanks Marc
     

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