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    • #28600
      Wright Arms
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      This ties in with my thread about case neck concentricity. How do those of you who check it measure case head runout? I have a method in mind that involves a turned mandrel and my lathe, but perhaps there is a better/simpler way? Please share what you do, if you would be so kind. Thank you.

    • #28604
      Doc Highwall
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      The best one I saw is this one, notice in the second picture that the case mouth locates on a ball bearing.

    • #28605
      Wright Arms
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      That looks like it would be quite accurate. I do not own a neck turner right now, so I used my lathe to turn the necks on a turned mandrel and watched for case head runout at the same time as I used the primer pocket to run my live center in. Kinda looking a 3 things at once. I only found 2 cases out of 60 that I rejected from my LC brass, but the ones that were out were WAY out. (.015″ +).

      I do not know yet if all this scrutiny will matter or not, as I am still working on the brass, but I will post my range results once I get to that point.

    • #28606
      Doc Highwall
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      What happens when you have case heads out of square, they get straighten upon firing, but this causes case stretching on the side that is lowest on the case face, and the case takes on a banana shape. This is not good for case run-out upon reloading.

    • #28608
      Wright Arms
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      I completely agree that logic dictates that what ever I can do to present the bullet to the barrel in the most square and concentric fashion should result in the smallest group on the target. Weather of not my shooting skills and the accuracy level of this rifle can show the difference or not is what remains to be seen.

    • #28610
      Scharfschuetze
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      If your bolt face is square to the bore, your cases will form to that and remain so and thus minimize any run out. If your bolt face is not perpendicular to the bore, then the head will form to that error on every shot as Doc points out above.

      Before you invest the time and effort to the project, check your bolt face. A good gunsmith can square it easily. If it is way out of square, then you may have to set your barrel back a thread and rechamber. That is a worse case scenario as usually only a very small amount of steel need to be removed, if any at all.

      If your rifle ends up at the gunsmith, then have him also square the recoil lug and mate the locking lug faces up with the receiver’s locking lug seats so that they both bear evenly.

      All the above can add up pretty fast and may or may not help.

    • #28612
      Wright Arms
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      Scharfschuetze;n7785 wrote: If your bolt face is square to the bore, your cases will form to that and remain so and thus minimize any run out. If your bolt face is not perpendicular to the bore, then the head will form to that error on every shot as Doc points out above.

      Before you invest the time and effort to the project, check your bolt face. A good gunsmith can square it easily. If it is way out of square, then you may have to set your barrel back a thread and rechamber. That is a worse case scenario as usually only a very small amount of steel need to be removed, if any at all.

      If your rifle ends up at the gunsmith, then have him also square the recoil lug and mate the locking lug faces up with the receiver’s locking lug seats so that they both bear evenly.

      All the above can add up pretty fast and may or may not help.

      I see. I was primarily concerned with the condition of my LC .308 parent cases, as I have no idea how many different firearms this brass was fired from nor what condition these arms were in. I have not detected any case head problems with any brass I have fired in my rifle before, so I do not expect any problems. Thank you for the replies.

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