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  1. #11
    Super Moderator Rory McCanuck's Avatar
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    When I start loading for a gun, the first thing I do is see what length they need to be.
    It is bothersome to make up a batch and then discover that they won't cycle through the action or fit in the magazine. Yes, I'm speaking from experience, oops
    It doesn't need to be difficult or even really precise, often I just seat them to the cannelure (crimp groove) and go from there.

    I'll make up a batch of 3 each at half grain increments (08, '06, Mag size cases) and measure the powder very precisely. My thinking is, I want each group to be as exactly the same as possible to give a true account of how accurate it is.
    Now, usually when you find an acurate load, it will sit in a 'node' where precise powder charge isn't so crucial.
    EG:
    50gr gives a 2" group
    50.5gr gives a 1" group
    51gr gives a 1" group
    51.5gr gives a 1" group
    52gr gives a 2" group

    There is a node in there where all those 1" groups will be in about the same spot.
    Once you find that node, now you can fine tune just what charge will be most accurate, but it might not be all that vital.
    One load in my 280 I've found that any charge between 61.5gr and 63gr will all hit in the same spot, regardless of temperature.
    Once you find that node, now you can fine tune the seating depth, and can quite possibly turn that 1" group into a 1/4" group.
    It doesn't always happen, and a 1" group is nothing to sneeze at, but it's nice to shoot a group and watch the hole just get a bit bigger with every shot.

    Addendum:
    The article is about seating to a precise length, according to ogive.
    That is the 'corner' where the parallel shanks of the bullet start to form their taper towards the tip.
    Usually the measurement from ogive to the bullet's base (not the cartridge's base) will be almost exactly the same.
    Often the measurement from bullet's tip to base can be wildly different, like 0.030" especially with exposed tipped bullets.
    So, when seating bullets don't get too wound up in getting the overall length the same from cartridge to cartridge.
    Either measure with a tool that registers from the ogive, or just trust that your seater is doing its job and the mechanical stops in the system stay in the same spot from round to round.
    :Hint: If you don't fiddle with it, they're all going to seat to the same length.
    Last edited by Rory McCanuck; 04-05-2019 at 01:38 PM.
    Don't blame me, I didn't vote for that clown. Oct 20, '15

  2. The Following User Liked This Post By Rory McCanuck

    Hidyn (04-07-2019)

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