Th measuring of group size

Discussion in 'Long Range Hunting & Shooting' started by mtmuley, Jan 3, 2008.

  1. mtmuley

    mtmuley Well-Known Member

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    Recent days of talking with friends and perusing other sites has me confused about how to measure a group of a string of shots that a certain rifle will shoot. How do YOU guys here measure "group" size? I have heard to take outside to outside of the bullets impact, and subtract the bullet diameter. Or, take center to center of the furthest impacts. Help. mtmuley
     
  2. britz

    britz Well-Known Member

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    you've pretty much got it. You take the farthest two holes in a group (all of the shots in the group, not the best three!) and you measure to the outsides of these two and subtract one bullet diameter to give you the center to center group. Not official but close enough!
     

  3. James Jones

    James Jones Well-Known Member

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    Its alot harder to measure the center to center of the shots so i measure the furthest outside edges and subtract the bullet diameter.
    Note though that if you take a paper target and flatten it out on a desk that the actual bullet hole is smaller than the bullet diameter but their will be a slight grey ring just around it , use your caliper and adjust it from the actual hole in the paper out till you reach the bullet diameter and make a not as to where this falls out then measure the group from the furthest outside edges of that grey ring then subtrack the bullet diameter. I have hurt alot of guys feeling by doing this but that the accurate way to get the group size.
     
  4. shootinfool

    shootinfool Well-Known Member

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    I have always used a pair of calipers to masure the outside to outside of the darker ring, not the acutal hole in the paper, of the furthest two shots, then simply subtracting the bullet diameter. This is the easiest and in my opinion the most accurate way, like james jones said, it is harder to find the exact center of the bullet holes and then masure the center to center group.
     
  5. eddybo

    eddybo Well-Known Member

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    I measure the size of an individual bullet hole then zero the calipers w/o moving them.......then just measure the outside to outside. Same thing no math involved.............then I just fudge a little from there:p
     
  6. Adam Lee

    Adam Lee Well-Known Member

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    i just guess! lol
     
  7. mtmuley

    mtmuley Well-Known Member

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    Thanks guys. The help is appreciated. mtmuley
     
  8. gbraach

    gbraach Member

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    1 moa group???

    So I got a follow up question for whoever can help.

    If your rifle shoots 1 moa groups. Shooting at a hundred yards, is your group size 1.05 inches (moa = diameter of group) or is your group size 2.10 inches (moa = radius of group)?
     
  9. James Jones

    James Jones Well-Known Member

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    one minute of angle at 100yds would be a 1" group measured by the DIAMTETER , measuring outside to outside of the widest spread minus the bullet diameter