Is Magpro Temp sensitive?

Discussion in 'Reloading' started by chad, Mar 20, 2014.

  1. chad

    chad Well-Known Member

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    Magpro seems to push bullets fast but im wondering if its temp stable?
     
  2. Boman

    Boman Well-Known Member

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    I'm tagging in. I'd like to try Magpro
     
  3. Bullet bumper

    Bullet bumper Well-Known Member

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    It's a double base ball powder as far as I can find out . Distributed by Western powder company so it could be a Winchester Western product.
    It does not seem to have a direct burning equivalent to the slowest Winchester ball powder so maybe a special mix?
    Anyway double base ball powders tend to be more temp sensitive than certain extruded single base powders but they are very chemically stable and long lasting if you keep them cool in storage .
    Also they exhibit higher energy per grain which is handy when powder space is lacking and meter through a measure very smoothly .
     
  4. FEENIX

    FEENIX Well-Known Member

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  5. 65WSM

    65WSM Well-Known Member

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    MagPro is a run of double base ball powder manufactured at the former Olin St Marks plant in Florida. It is the reason that Hodgdon developed the "Extreme" line of powder at the Australian Defense Industries facility in Australia (French ownership).

    MagPro is amongst the most temperature sensitive powders available. The US military uses similar ball powders (close to Win 748 and 760 in handloader form) from St Marks but not for accurate sniper ammunition. I have a friend, a retired Physics professor, who tested small arms and ammunition for the US Army Aberdeen Proving Ground (Nome in the Winter followed by the Panama Canal Zone) and they chose Reloader 15 which is a Bufors stick powder made in Sweden because of its temperature tolerance.

    MagPro is my favorite powder because of the velocity it produces with 140 Accubond or Berger Hunting VLDs in .270 WSM. For some reason MagPro disappoints in the 6.5 WSM for which I have two rifles. In the 6.5 WSM it produces less velocity than Retumbo and VV N570 using 130 and 140 gr bullets.
     
  6. chad

    chad Well-Known Member

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    I guess I have two pounds of powder I need to sell