Seating depths ??????

Discussion in 'Reloading' started by cbryant, Nov 26, 2012.

  1. cbryant

    cbryant Member

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    Oct 2, 2011
    Iam gonna load some berger 140 vld for my 6.5-284 and i was checking distance the distance to lands with the vld its at 2.487 to the ogive and my 130 accubonds are 2.494 fo the ogive, should i start my seating depth at the 2.494 because this load shoots real good or start at the 2.487 or did i screw something up and this is not my true distance????
     
  2. SBruce

    SBruce Well-Known Member

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    Oct 31, 2009
    It's common for different bullets to have a different measurement in this regard.
    They vary in bearing surface length and Ogive length in addition to overall length.

    In my 270 WSM, my OAL with the 150 VLD just kissing the lands would be 2.925", but the 140 Accubond seated to just kiss the lands would give an OAL of 2.990".........or, .065" difference between the two bullets. However, the case head to ogive (comparator measurement) would only differ by .005" between those two bullets. In contrast, comparing the 150 Ballistic Tip to the 140 TSX Barnes BT; OAL would be .080" different when both are seated to the lands, but the comparator measurement would only be .002 different.

    If it were me, I'd start my testing with 2.490 and call it "kissing" or "light jam" with the Bergers.
    Then if not satisfied, you can back off from that depth without raising pressures. Pressures should actually decrease with the bullets further off the lands.

    Hope this helps, good luck.
     
    Last edited: Nov 26, 2012

  3. RT2506

    RT2506 Well-Known Member

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    Jan 10, 2008
    Go to the top of this reloading section and read the sticky on how to load the VLDs for accuracy. They will shoot waaaaaaaay off the lands so you don't run the chance of sticking a bullet in the bore in a hunting situation by having them jammed into the lands when you go to unload your rifle.