Berger Integrity

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by RH300UM, Aug 14, 2011.

  1. RH300UM

    RH300UM Well-Known Member

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    Does anybody have info for the maximum velocity that a Berger bullet can be pushed to before coming apart? I know that twist rate has a hand in the outcome also. I am shooting 180 VLD,s at 3334 fps average with a 1 in 9 twist. I am having what appears to be bullet integrity problems at this velocity. I have called and talked to Berger but can not get a definite answer from them. I was just wondering if anyone has had any problems or experinces that they can share.
     
  2. Broz

    Broz Well-Known Member

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    I have had no problems with the 180's at 3200 in a 9 twist and have shot 100's. I think Eddybo had some issues with them somewhere over 3400 in an 8 twist. If he doesn't join in here maybe send him a pm.

    Jeff
     

  3. Mikecr

    Mikecr Well-Known Member

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    You can't ask for a limit 'for Berger bullets' because they are not all the same.
    But I had defined(as best I could) the RPM limits of Berger VLDs quite awhile back. Berger didn't like it one bit, but it has always held as useful(still for VLDs).
    For your situation:

    (720*MV/TW)/1000
    (720*3334/9)/1000
    KRPMs = 267 [your rate]

    (0.308-CAL)*238.095+290
    (0.308-.284)*238.095+290
    KRPM LIMIT = 296 [The point of expected failures]

    For the Eddybo mention:
    (720*3400/8)/1000
    KRPMs = 306 [This exceeds the 296 limit]

    So, it's not RPMs(or the energy to produce them) causing your failures.
     
  4. RH300UM

    RH300UM Well-Known Member

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    Thanks for the info.
    I am thinking that the Berger in 7mm 180gr. is coming apart on me due to the fact that on a few shots taken that the only thing hitting the paper target at 200yds. is shrapnel!!! I have 206 rounds down the barrel now and this has happened 3 times.
     
    Last edited: Aug 14, 2011
  5. Mikecr

    Mikecr Well-Known Member

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    If you don't have a borescope, a local gunsmith probably does. I'd have the bore/crown looked at. It's hard to guess at, so that's just where I'd start.
    If there is an issue there, you might salvage the situation with a going of Tubb's FinalFinish.
     
  6. RH300UM

    RH300UM Well-Known Member

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    Not sure as to what you are thinking????
    This is a new rig with a Brux barrel.
    Called 'smith. Was told to try a differnt lot of Bergers.
    The ones I was using were in the old yellow box. Thinner jacket?
    Might be as simple as this.
     
  7. Mikecr

    Mikecr Well-Known Member

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    The new 'Match Target' VLDs have thicker jackets than the original VLDs(now called 'hunting' VLDs). This might work around whatever issue there is, at a cost of killing efficiency. But I don't think it's the bullets.

    Are you sure it's a 9tw, and not an 8tw?
    Have you checked the twist with a cleaning rod?
     
  8. Ridge Runner

    Ridge Runner Well-Known Member

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    yep, I've had problems, (3 times out of 3) shooting .264 140's at 3160 fps from an 8 twist, impact ranges were 230, 456, and 493 yards, no bone was encountered and the bullets penetrated maybe 2" total. yet most posts say they are great bullets, I just can't accept that from what I have saw.
    RR
     
  9. RH300UM

    RH300UM Well-Known Member

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    HOLY S--T !!!!
    I have a 1 in 8 twist. Ordered a 1 in 9. I never checked it I just assumed. Now I am the ass. THANKS Mikecr.
    Ordered up some 180 SMK's. "smith says these will handle the situation.
     
  10. eddybo

    eddybo Well-Known Member

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    You just scared me. I am running them a little hotter than that in a 6.5WSM and was planning on shooting an antelope with it in a couple weeks, but probably at 700-1K yards, but stuff happens and longrange plans often end with short shot opportunities.