Whats the dif between IMR 4350 and H4350

Discussion in 'Reloading' started by earlybird, Mar 25, 2013.

  1. earlybird

    earlybird Well-Known Member

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    Dec 21, 2011
    Just what the title says. What is the difference between the two 4350's?
     
  2. emn83

    emn83 Well-Known Member

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    Feb 11, 2012
    H4350 is an extreme powder, it is less susceptible to temperature changes. Also, doing a real quick look at my Berger manual, it looks like they have different min/max loads, would have to check the Hodgdon website for sure, but guessing they have different pressure curves
     

  3. bbutturff

    bbutturff Well-Known Member

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    Feb 18, 2011
    While they are close in burn rate they have different pressure curves and are not directly interchangeable. Always follow published load data, start about 10% below published max and cautiously work your way up.
     
  4. Lefty7mmstw

    Lefty7mmstw Well-Known Member

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    At one time many moons ago; nothing.... That has changed though and Hodgdon has turned h4350 into a shortcut "extreme" powder that simply burns about the same speed as the other 4350 and isn't the original stuff. I really don't like the H4350 as well but do shoot both powders in at least one rifle.