bullet fpi question

beantole

March 15, 2004 10:52

OK, assuming my charts are correct a typical 38 special has knockdown power of about 220 fpi and a Makarov 9X18 mm bullet has a fpi of 258.
How can that be when the powder charge in the 38 special is so much greater than the powder charge in the Makarov 9X18 mm ?? I just don't understand it. Thanks.

Bruce

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  Tailgunner1954

  March 15, 2004 11:22

  Are you using Muzzle Energy (MxVxV/constant I can't remember) or Muzzle Momentum (MxV)?
  With ME, the velocity squared is what's causing it to look like it does.
  In compitation they use "Power Factor" which is MxV/100
  
  

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  Some guys like a mag full of lead, I still prefer one round to the head.

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  beantole

  March 15, 2004 17:35

  I don't know anything about those math formulas. I assumed foot/pounds was somewhat equivalent with knockdown power. I still don't understand why the smaller Makarov 9X18 apparently has more knockdown power than the larger 38 special.
  
  Bruce

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