MOA

knucklehead14

July 31, 2003 19:30

what does MOA stand for?
I Think it has something to do with group size but I`m not sure.
Thanks.

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  knucklehead14

  July 31, 2003 19:30

  If is 1" @ 100 yds., 2" @ 200 yds
  What is it at 400 yds ?

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  redcedars

  July 31, 2003 19:41

  minute of angle
  
  1/60th of one degree, 1" at 100 yards
  
  A "one minute" gun is capable of 1" groups at 100 yards.
  
  redcedars

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  nononsense

  August 01, 2003 01:10

  knucklehead14,
  
  I know that this will sound like nitpicking and it is but Minute of Angle at 100 yards is equal to 1.0472" not just one inch. Use this link for one of the easiest explanations that I've read.
  
  http://www.aeroballisticsonline.com/ballistics/minuteofangle.html
  
  I'm not being critical of redcedars at all since most of the time we all think of MOA as being 1 inch at 100 yards, it's faster and simpler. But, when it comes to measuring groups in any form of competition, accuracy of measurements is paramount.
  
  Best.

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  gskyhawk

  August 01, 2003 03:40

  you could add that a sub MOA gun will hold its group at what ever the range is ie
  1 inch or less at 100 yards
  2 inches or less at 2oo yards
  3 inches or less at 300 yards
  for the average person / hunter MOA is 1 inch at 100 yards
  they may get down to the thousands of inch in bench rest compettions but for the average Joe going out to see what is rifle can do 1 inch is fine
  Not taking any thing away from nononsense( whos right ) just saying most people don't get that picky[:D]

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  Travis Hallam

  August 01, 2003 04:42

  Another point to bring up is that the "average joe" groups are measured from the center of the bullet holes and not the outside diameters. In competition I imagine they take the ouside diameters and subtract the bullet diameter. That is how you get groups that are .01 MOA (or less).
  
  Mad Dog

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  easygo6

  August 02, 2003 18:49

  Thanks Travis,
  
  I appreciate learning something knew tonight!
  
  SEMPER FI

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  nononsense

  August 02, 2003 22:18

  There are as many explanations as to how a target gets measured as there are targets and shooters. Here are a couple of responses regarding match target measuring that I copied from a benchrest site.
  
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  "At benchrest matches, groups are measured under magnification, using a caliper-mounted reticle plate with a scribed circle. Centering this circle on the bullet holes largely eliminates problems with trying to find the edge of the hole, and the resulting center-to-center group measurements are pretty accurate."
  
  "Still, the caliper's ability to measure in 0.001" increments does not mean measurements are correct to 0.001". Actual precision of group measurements is probably on the order of plus or minus 0.005" (five thousandths), and remeasurement by a different scorer or under different lighting conditions will often if not usually result in a slightly different group size."
  
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  "...when groups are measured at matches, the scorer only reads the instrument in .001 increments. The computer, when averaging the data, converts to four places, or tenths. For example, a combined agg of .232, .197, .282, .205, .221 would add up to 1.137, divided by five for an agg of .2274."
  
  *********************************************************************
  
  Just for the sake of information and discussion.
  
  Best.

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