Stadia-relation formula

Discussion in 'Long Range Scopes and Other Optics' started by sscoyote, Jan 3, 2005.

  1. sscoyote

    sscoyote Well-Known Member

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    Feb 26, 2003
    For the past yr. or so now i've been checking out something that's been working pretty good so far. While i was looking into the mil-relation formula, i started wondering if the system could be used with any reticle with a stadia out of the optical center of the scope once it's subtension was known. Turns out it works just fine, especially when all a shooter has is just a plex reticle. Here's how it works-- just substitute the stadia subtension measurement for the mil reading, i.e. target size x 100/stadia/# stadia units. For example i was using a 4-12X Burris Mini on a 17 Mach IV XP for coyotes. The plex gap measures 5.7" @ 12X, so plugging the #'s in figuring a 10" back-brisket coyote gives,

    10 x 100/5.7/# stadia units (SU), or

    1 SU= 175 yds.
    .9= 200
    .8= 220
    .7= 250
    .6= 290
    .5 (x-hair)= 350
    etc.

    Seems to be working pretty good for me so far. Anybody ever use anything similar.
     
  2. Aussie

    Aussie Well-Known Member

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    Apr 29, 2004
    SSCoyote ,
    Leupold used a similar principle on some of the Vari X 111 scopes for range estimation and does on their current Boone and Crocket and Varmint Hunter's reticles .So have other manufacturers .
    Can be done with any duplex reticle and some others .
     

  3. sscoyote

    sscoyote Well-Known Member

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    Feb 26, 2003
    Yeah-- i've seen their systems. I think the advantage of the "modified mil-ranging" system here is that it can be used for any size target (Leupold's is calculated for a deer size target only), it can be used with fixed power or variable, is quick to apply in the field, can be used with any stadia subtension, and doesn't require any fiddling with the power ring.