Burris 8x32 bmd

Discussion in 'Long Range Scopes and Other Optics' started by cdog, Nov 23, 2006.

  1. cdog

    cdog Well-Known Member

    Messages:
    50
    Joined:
    Dec 28, 2004
    Hello all. I have a question about the bmd reticle in my 8x32 burris. Is there a way to figure out what the hash marks represent at something other than 14x? Preferably 32x or perhaps 24x? It seems like a lot of clicks at 600 yards if I want something more than 14x magnification. The clicks work well, but I was looking for quick and easy. Thanks in advance for any and all responses,
    Cdog.
     
  2. sscoyote

    sscoyote Well-Known Member

    Messages:
    1,255
    Joined:
    Feb 26, 2003
    There really are 2 ways to do it. The best way is to go out and measure the reticle as accurately as possible from the bench @ the higher magnification (including the windage mil-dot subtension). With 32X this should be easy. Once u calculate the dot to dot subtension of the mil-dots the diameters of the dots should be easy. They should be .2 of whatever the dot to dot subtension is @ 32X IF the dot diameters r .2 mil. at 14X. I think they r, but don't know for sure.

    The other way to do it is to apply an inversely proportional equation to calculate it since as magnification INCREASES, reticle subtension DECREASES, and it's supposed to be linear, but that is dependent upon the power ring being calibrated properly-- something i don't trust most of the time.

    I think u r on the right track here by doing a recalibration as i never understood why Burris didn't calibrate the reticle for the highest magnification. I mean, why buy a 32X scope with a ballistic reticle that's calibrated for an intermediate magnification??

    Something to think about tho. with the recalibration is now u're only going to get a little more than about 6 inch per hundred yds. (IPHY) reticle compensation to the lower post since 14X is about 40% of 32X, and therefore 6 IPHY is 40% of 14.5 IPHY (the subtension of the lower post tip @ 14X). That's not much really, but u could certainly add clicks beyond the lower post tip if u wanted to go out farther.
     

  3. cdog

    cdog Well-Known Member

    Messages:
    50
    Joined:
    Dec 28, 2004
    Thanks a bunch for your reply. Although the scope has worked perfectly for about 2 years its a case of wish I knew then what I know now. I think I understand what you are saying, but on a 223 shooting 69gr matchkings at 600 yards @3000fps thats about 102" of drop. So says the infinity program I have. So I came up with a compromise yesterday at the range, I used the bottom hash mark to start with which gave me about four and a half inch head start at 100 yards. Then I added about thirteen and a half inches with the dial. I did this for two reasons, one is I have read the more centered the erector tube is, the better the allighnment of lenses so the better the image? Also the scope is rather lacking in adjustment, it only has 19" of up according to the web site.
    Does this sound ok to you? I dont think the 223 is a flat enuf shooter to use the reticle at 32x the way I would like. So that only leaves one more question, Are the nightforce reticles calibrated at max power? I beleive this is where I am headed next!! Just cant decide between the 3.5x15 or the 5.5x22??!! Thanks again for your reply.

    Cdog.
     
  4. sscoyote

    sscoyote Well-Known Member

    Messages:
    1,255
    Joined:
    Feb 26, 2003
    Good idea-- should work well for u. Don't know about the NF's-- i don't have 1. But all the Leupold's r.