.243 Barnes TSX & TTSX Lapua cases Vihtavuori N550?

Discussion in 'Reloading' started by alasdair, Jul 26, 2013.

  1. alasdair

    alasdair Member

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    Jun 20, 2013
    Hi there,

    novice re-loader from Scotland, where I principally hunt Roe Deer,

    I've been trying out loads for .243 Barnes TSX (85gr) & TTSX (80gr) using Lapua cases, for my Sako 75 (stainless, synthetic) 21.5" barrel.

    I've had a good search round different threads here and elsewhere.

    As with you lot propellant powders are a bit thin on the ground.

    I started off with Hodgdon H4350 using loads provided by Barnes and/or Hodgdon, but even at maximum (no pressure signs) results were modest and MV was slower than Hodgdon or Barnes predicted (less than 3000fps) and it was very dirty, producing significant change of POI as the barrel got dirtier!

    I managed to get some Vihtavuori N550 and using the Lapua/Vihtavuori recommended loads for the TSX (85gr) and a big jump to lands (0.086"), at less than maximum load and with no signs of pressure, I am getting 3300fps and less than 1.0" groups @ 100metres, with little change in POI from clean and cold. Much cleaner burning!

    I'm inclined to think the loads recommended by Barnes/Hodgdon and H4350 are a bit timid? Anyway, I'll stick with the N550 'cos it works for me.

    However, I have no Lapua/Vihtavuori N550 recommended loads for the TTSX (80gr), despite looking everywhere.
    Since in general terms it seems to be that the slightly lighter TTSX has recommended loads (whatever the powder used) slightly higher than the TSX: would I be right in thinking that I could safely use my N550 TSX load (41.4gr as it happens) as a safe starting point for loading the TTSX?

    My reasons for using the Barnes are two-fold:
    we are beginning to see some land-owners over here demanding lead-free,
    but also I am impressed that there is less meat damage/loss with the Barnes than my previous (Sako Gamehead) ammo, and less risk of that meat being lead contaminated.

    Great forum chaps, thanks!

    alasdair.
     
  2. azsugarbear

    azsugarbear Well-Known Member

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    Welcome aboard. I shoot 243 as well and I have been wanting to try some V V 500 series powder with my 105 gr. bullets, but it seems hard to come by these days. As a general rule: given the same caliber, the lighter the bullet, the bigger the powder charge required to reach max pressure/velocity. So take the charge for your 85. gr. bullet and back off about 2.0 grains, then start working up to your max load. Max load for your 80 gr. bullet should be about .5 to 1.0 gr. higher than your 85 gr. bullet.
     

  3. alasdair

    alasdair Member

    Messages:
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    Jun 20, 2013
    Thanks azsugarbear,

    I appreciate your advice and respect your wisdom.
    But here's the problem:
    for .243 TSX 85 gr, Lapua case Lapua/Vv recommend starting load N550 39.5gr to maximum 42.0 gr. My best load to date seems to be 41.4 gr.
    But Lapua/Vv don't give a recipe for the TTSX.

    As you say: as a general rule it is seems to be that for similar bullets in same case, same powder, same rifle scenario the lighter bullet takes a slightly higher load.
    e.g. .243 Win. and H4350

    from Barnes reloading data:
    TTSX 80 gr min: 41.5 gr to max: 45.5 gr
    &
    from Hodgdon reloading data:
    TSX 85 gr min: 37.3 gr to max: 40.5 gr

    If I subtract 2.0 gr from my best 85gr load of N550 that will take me below the starting load for the 85 gr, and I'm wanting a starting load for the 80 gr - which must surely be higher?
    . . and since most of the tables caution against using less than minimum/starting loads, I'm wary . . remember I'm a novice!

    It seems to me that given a same rifle, same case, same powder scenario and with bullets as similar as the .243 TSX & TTSX, that I would be pretty safe using my TSX load (41.4 gr) as a starting load for the TTSX. But I'm a novice. So I need to check out my assumptions!


    Why bother, when I have a load that I'm happy with for the TSX 85 gr?
    Well with bullet availability being precarious it would be nice to have a load for the TTSX in the event that I can't get TSX but can get TTSX.

    What on earth did folk do in the days when there was no internet or forum?

    Thanks again,

    alasdair.
     
  4. azsugarbear

    azsugarbear Well-Known Member

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    Sep 20, 2005
    Every manufacturer has their own data / load tables. As you note, they can vary widely - even with the same bullet and powder combinations. I believe potential legal liability has a lot to do with where each mfg. draws the line.

    So what you have is a lot of book wisdom stacked against your own practical experience. You have a load the works well for you with the 85 gr. bullet. It is not a max load. So drop down a couple of grains and start working back up with your 80 gr. bullet.

    Don't worry about shooting below min. loads. There is no danger in shooting a load under min. load data. The bullet just won 't perform well. Even std. calibers such as the .308 that are load down to subsonic velocities (1,040 to 1,080) fps still function in a rifle and will not leave a bullet stuck in the barrel. The real danger is loading too hot and damaging your rifle, or worse- you or the shooter next to you. Go with what your experience has shown you with your own rifle and load development work.
     
  5. mooser

    mooser Well-Known Member

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    Jan 26, 2007
    Barnes book shows the exact same load for both the 85tsx and the 80 ttsx
     
  6. alasdair

    alasdair Member

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    Jun 20, 2013
    Thank you Gentlemen,
    that's both helpful and reassuring - now all I need is some time to myself to load some up and check MV and zero!


    alasdair.
     
  7. Pistolero

    Pistolero New Member

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    Feb 1, 2014
    Be careful with going below minimum recommended loads listed in reloading manuals. Guns have been destroyed and people hurt.