Bersin Concentricity Tool

Discussion in 'Reloading' started by bailey1474, Apr 28, 2006.

  1. bailey1474

    bailey1474 <strong>SPONSOR</strong>

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    Anybody have any experience or opinions on these? I got to play w/one a couple of weeks ago and was impressed. Pretty neat tool. I'm still not sure if I want to spend that much money on one though.

    Thanks,
    B.J.
     
  2. MagMan

    MagMan Well-Known Member

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  3. älg

    älg Well-Known Member

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    Looks interesting. Does it then fix the RO problem of the bullet in relation with the case or neck?? Won´t this twist the neck somehow??
     
  4. Darin S Johnston

    Darin S Johnston Member

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    Bill go ahead and get one, your best friend at the long star shoot had one shooting those good groups at 1000 yards, he also said that he will spot for you at the up coming shoot at ricks /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif
     
  5. Bart B

    Bart B Well-Known Member

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    I don't think I would accept ten of them free. Their problem is they push the bullet back straight. Too much of the time when that's done, it loosens them in the neck. That's because the neck will also bend and become oval shaped at the mouth.

    Crooked seated bullets are typically very well aligned with the case neck. To straighten them out, you have to bend the neck on the case. And do so without disturbing the bullet's position in the neck.

    This can easily be done by using a bullet puller with a collet sized a bit larger than loaded round neck diameter. First measure your rounds for bullet straightness, then mark their high point. Put the bullet puller in the press, then push up a bullet in it from below with the high point mark towards you all the way to the shoulder, then gently tighten the collet a bit. Push the bottom of the round back a bit, remove the round then check its out of round value. You'll soon learn about how much to push the bottom of the case to straighten the runout a certain amount.
     
  6. lerch

    lerch <strong>SPONSOR</strong>

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    Darrin????

    I thought you were dead man!!!!! I heard you were blown to peices in some wierd 8mm Mauser explosion!!!! /ubbthreads/images/graemlins/blush.gif /ubbthreads/images/graemlins/blush.gif /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

    You all better watch out at Ricks shoot, daddy is coming down and I got a new 22-250 to whip on yall with. /ubbthreads/images/graemlins/laugh.gif /ubbthreads/images/graemlins/grin.gif

    Sad thing is those guys from texas you all invited will probably beat all of us with there damn bench guns!! /ubbthreads/images/graemlins/grin.gif /ubbthreads/images/graemlins/grin.gif

    See ya in a week

    steve
     
  7. Ballistic64

    Ballistic64 Well-Known Member

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    I'd agree with Bart on this tool screwing with the neck tension of your loaded rounds.
     
  8. Ernie

    Ernie SPONSOR

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    I have been told the same thing about it changing the neck tension. I have one though, and it has not been detrimental (as I have been able to tell) to my shooting.
    I have a couple of other friends who have one and they consistently shoot 1k (IBS) and they are very satisfied with it's performance.
    With that being said, I have not done the kind of litmus test that would be required to prove it one way or the other.
    My guess is, most people who speak negatively about the product have not done so either.
    Since I have been using mine, my results have been very satisfying.
    Wish I could be more scientific in my response, but I can't /ubbthreads/images/graemlins/grin.gif
     
  9. Ballistic64

    Ballistic64 Well-Known Member

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    Your right XP,Ive never used one.I first saw them advertised by Kinnemans and thought it would be a neat tool but then started thinking that a piece of fired brass is going to be as straight (uniform with the chamber) as its ever going to be from fireforming with the exception of wall thickness in the body,neck etc.
    So with all things copasetic with a fireformed case that is being reloaded,ideally the variance in neck thickness is the only thing left to screw with bullet runout (aside from reloading practices that arent quite right...misadjusted dies etc.)
    Then I thought how is a Bersin going to true a bullet to be in the centerline of the bore if the neck wall thickness isnt even.I dont think it can.You may be able to reduce runout where the Bersin is measuring but for every thousandths you push the bullet to reduce run out, the other end of the bullet is increasing in run out.
    So in my mind,with prepped fireformed brass and proper loading the Bersin was another concentricity gauge that I didnt need,I already have one.
    Is my thinking correct?
     
  10. EddieHarren

    EddieHarren Well-Known Member

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    I'm with BartB, I've never used one but, I'm sure it won't work.
     
  11. Bart B

    Bart B Well-Known Member

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    [ QUOTE ]
    I have not done the kind of litmus test that would be required to prove it one way or the other. My guess is, most people who speak negatively about the product have not done so either.

    [/ QUOTE ]I spoke negatively aabout it because of experiences years ago shooting service ammo in match grade rifles. Folks would take .30-06 ball or AP ammo, chuck the bullet in a pulling collet, then bend the round a bit to straighten the bullet's alignment with the case axis. None of them shot as accurate as when the loaded round's case neck was held in a larger bullet pulling collet then the neck bent so as not to disturb the neck tension on the bullet. So, when this "bullet bending" rig came out some time ago and I was asked back then about it, I said 'twouldn't work well.

    This was the norm back in the '50s and early '60s when M1 Garands were the only service rifle allowed in military style matches. 'Course that was before epoxy bedding and folks used match book covers or sand paper between the trigger housing flats so the receiver would be held tigheter in the stock.

    All the above aside, if one does anything to loaded ammo that makes it consistantly shoot more accurate, do it; again and again and again......
     
  12. Darin S Johnston

    Darin S Johnston Member

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    stevyboy bring that laddies cal down "kimber" HaHaHa
    the texas boys, well you know the only things that come out of the big T are steers and q....s.
     
  13. lerch

    lerch <strong>SPONSOR</strong>

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    Well as long as you got some of them kick @$$ hot links again I will be there

    steve