G7 bc for .277 165 grain matrix vld

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by Paramudd, Jan 20, 2012.

  1. Paramudd

    Paramudd Active Member

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    Can anyone give me this info?
     
  2. sbruni

    sbruni Well-Known Member

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    Did you ever find out?
     

  3. MuleHunter

    MuleHunter Well-Known Member

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    I have done extensive testing with the 175gr. It has a G1 of .6435 and a G7 of .3225.

    My friend who is as anal as I am with checking the BC's has tested the 165gr at a G1 of .638, so the G7 profile would be a .319.
     
  4. C.O. Shooter

    C.O. Shooter Well-Known Member

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    Did you happen to test these in the 270 WBY?
     
  5. MuleHunter

    MuleHunter Well-Known Member

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    No. These were tested at a muzzle velocity of 2,990fps with the 175gr and at 2,950fps with the 165gr.

    Brian Litz tests Berger bullets from a 3,000fps muzzle velocity down to 1,500fps and that average BC across those velocity bands are the ones Berger lists on their website for their bullets. My testing gets as close to his results as possible without using sonographs at multiple ranges.

    In my experience when you approach the 3,150-3,300fps range the average BC gets higher. My goal for testing these bullets was to mimic Litzs' testing as close as possible so that the average shooter shooting them in the 2,800-3,000 fps range would have an accurate average BC to start with.

    The cartridges used were a 270 WSM and a 270 Win

    I did a little write up on how I tested the 175gr in the ELR section of this forum.
     
  6. FEENIX

    FEENIX Well-Known Member

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    That's an excellent write up and thanks for sharing.

    Do you mind sharing your 165/175 accuracy loads for the .270 Win? Thank you in advance.
     
  7. MuleHunter

    MuleHunter Well-Known Member

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    Norma brass for the WSM. Fed 210GM primers. .020 off the lands.

    H1000 for both cartridges.

    270 Win. Win brass, br-2 primers, .020 off the lands.

    Work up in small increments like .2 gr

    Im very anal about load prep with charge weight, brass prep, and bullet sorting. The Win is shooting .35 MOA, the WSM is 1/4 MOA or better.
     
  8. FEENIX

    FEENIX Well-Known Member

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    Cool! What's your starting powder charge? Many thanks!

    Ed