Powder Graph with the redding 3BR measure.

Discussion in 'Reloading' started by zetor, Mar 4, 2017.

  1. zetor

    zetor Gaston beat up John

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    I use a lot of H110 powder. I reload for .357, .44, and .500 S&W. The charges go from 15-43 grains with those calibers and the bullet weights I load for. I always sort of ball parked it with the micrometer barrel adjust screw and then fine tuned it until I got what charge weight I wanted. This normally took 4-6 tunings to get it dialed in. The papers that came with the measure mentioned making a graph, but I figured it would look more like a scatter plot and not worth fooling with, but that's definitely not the case.

    X=barell reading
    y= charge weight (grains)

    That's the best straight line I could do through those points.....and it's a good one.
    Using the formula for the line, I'm not off by more than a .2 grains when checked on the scale.
    Just thought I'd mention it in case you had a powder you use for multiple calibers. It might be worthwhile to make one of these.
     

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  2. Verbal101

    Verbal101 Active Member

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    Just making sure I understand this - X axis is the setting on your powder measure? So this allows you to dial in a new weight without all the, what shall we call it, educated guessing?
     

  3. zetor

    zetor Gaston beat up John

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    Yeah that's all it is. If I just had a few loads and never tried anything new, I'd just write the adjustments down. The equation to this line is y=1.11x+4.9
    So if I want 40 grains, I just subtract 4.9 and divide by 1.11 and I get 31.6 for the barell adjust setting.
    It's pretty much dead on if the temperature is fairly constant. I have an unfinished unheated work area and if it gets cold, it will be off a little, but not much.
     
  4. Verbal101

    Verbal101 Active Member

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    That is very handy. Thanks for sharing!