Barrel temperature between shots??

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Mule, Jul 18, 2007.

  1. Mule

    Mule Well-Known Member

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    Reference : 264 Win Mag Sendero SF II

    I am performing load testing and need to know how warm/cold the barrel needs to be before groups of two shots. I noticed that on this particular rifle, I would get the first two shots from a cold barrel at about 1/2 MOA at 200 yds and then once the barrel was "warm" (not hot) the group would open up immediately to 1-1.5 MOA. Is this normal for such sensitivity and does this indicate that I really need to "cool" the barrel back to 75 deg prior to the next two shot sequence. I am concerned that this is having a dramatic impact on finding the load that this rifle likes.

    Thanks for the advice

    Mule
     

  2. Eaglet

    Eaglet Well-Known Member

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    Mule,

    I know Senderos are free floated from factory, still I would take the stock off and check for any indications of barrel rubbing against anything or if the bedding has any similar marks. If after checking for rubs and making sure the action bolts are tighten to specifications and if that third shot is still walking away, then is time for a skim bedding.
     

  3. silvertip-co

    silvertip-co Well-Known Member

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    Monday when I was sighting in my new 7 RemMag i shot ten shots and the shot string dropped 4" the bbl got so hot. I let it cool 45 min then it was back on exact zero where i set it. After that I only shoot two then rest two then rest etc.
     
  4. Mikecr

    Mikecr Well-Known Member

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    These are not benchrest cartridges..
    If you get 2 together from a cold hunting barrel.. That is, 2 into your killzone.. What more could you want?
    How many shots do you need in the real world?
    The answer is -ONE

    Don't confuse field accuracy with BR consistancy. They are not at all related.
    If you need accuracy, measure from the center of your mark to the center of each impact. forget hole to hole grouping.
    If you need cold barrel accuracy, let the barrel cool an hour between each shot.
    If you need cold-clean barrel accuracy, clean it while your waiting an hour.
    If you need cold-clean barrel -field accuracy, take each shot off a bipod in the dirt, or fence post or whatever.

    It's alot of work, but a rifle that does well here is your best friend for sure.
     
  5. Bug

    Bug Active Member

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    Ya' know, IF I could make myself really BELIEVE that, things would be a lot easier. You make sense... If THE VOICES would just shut up!
     
  6. Mikecr

    Mikecr Well-Known Member

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    This is LongerangeHUNTING.com
    Don't listen to voices saying LongrangeTARGETSHOOTING.com

    Snap out of it!
     
  7. goodgrouper

    goodgrouper Writers Guild

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    Some barrels have stresses in them from less than perfect metallurgy or machining and when they get to a certain temperature, they will tend to shoot poorly. We just cross our fingers and hope we don't get one of those barrels. If we do get one, all one can do is let her cool off before shooting another shot.