Zeiss Z-Plex for ranging targets

Discussion in 'Long Range Scopes and Other Optics' started by Bill Maylor, Aug 24, 2008.

  1. Bill Maylor

    Bill Maylor Well-Known Member

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    Just pick up a Zeiss 6.5x20x50 Conquest rifle scope. I did not see any info on using #20 Z-Plex for est, distances. Dose anyone have a clue? This is my first Zeiss rifle scope. My other scopes have a mark or dot on the power band. Idont see any on this scope. Any help would be thankful. Bill Maylor.
     
  2. sscoyote

    sscoyote Well-Known Member

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    Bill, i'm not sure what the subtension of the plex post tips are with that reticle, but it should be advertised in their catalog somewhere. Or u could just go out and measure it yourself. Probably best to measure at 100 yds. although the measurement can be done at any distance really.

    Here's the rangefinding formula as stated in the other post (inches to yds.)--

    tgt. size x range of reticle subtension measurement / reticle subtension / quantity of reticle gap tgt. occupies (decimal equivalent) = range

    If the subtension isn't wide enuf at the upper magnification then it can be adjusted some by turning the power down proportionally, i.e. as maginfication DECREASES, subtension INCREASES (inversely proportional), so if it measures 4" between posts @ 20X it will be very close to 8" @ 10X.
     

  3. Bill Maylor

    Bill Maylor Well-Known Member

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    Thanks sscoyote, I will try the measurement at 100yrd AM. I will be able to do this in my yard. I will post what I find. Bill Maylor
     
  4. sscoyote

    sscoyote Well-Known Member

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    "Thanks sscoyote, I will try the measurement at 100yrd AM. I will be able to do this in my yard. I will post what I find. Bill Maylor"


    Exactly!!

    I've found a good place to practice rangefinding with reticles is often right out the window of my old house (assuming discretion, of course). When i was studying this part of the LR shooting game, i was looking out the front window of my old house 1 day when i noticed all the signs that were along the street that ran more than 1000 yds. away from my house. All i had to do was go out and measure them and range back to my dining room window. What i'd done really was established a sort of "optics lab" with different stds. that i could use to play with my optics. It was really a great project. Once i knew the subtension of my reticles it was easy to reticle-range these signs and see how close i could come to the true (lasered) range. Then once i figured out that reticle subtension changes porportionally with magnification change it really got fun. Now i could take a 3-9X plex-reticled scope that i knew the subtensions of, and calculate a power that would be needed to bracket a certain sign at a certain distance--drove my wife crazy for awhile, i tell ya'.

    Interestingly i often wanted to help my buddies when they came over the house to help them establish a long-range shooting system with their plex-reticled scopes too (usually for coyote hunting during the winter). The problem was if they were using an optic that we didn't know the subtension of (many scope companies have the subtensions advertised in their catalogs), then i didn't know how to measure it really at the time. 1 day i was riding my bike down the road when i stopped at an intersection. I looked over at the stop sign and there was my answer. Many road signs use posts that have .25" holes drilled in them at 1" intervals, and there was 1 out in front of my house at something like 95 yds, i think it was. I used that "std." many times after that, and could get measurements off those holes when the light was right.
     
  5. royinidaho

    royinidaho Writers Guild

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    sscoyote,

    I liked what you posted. I did something similar but not as intensive.
    I used a 36" piece of orange kids floaty thinger and placed it at different distances out to 1K.

    After I got good at it I put it at unknown distances then measured the distance with a +/- 1' DGPS unit. I got pretty comfortable.

    The big disappointment came when I learned from laying in the field and ranging elk that they don't have a standard size and wouldn't let me stick that orange thinger on their side.;)

    Bill, I'm bettin' you'll like that scope. I put mine through the first field test this weekend and it passed with flying colors. The side focus seems very well calibrated and the clicks are spot on and repeatable.

    Keep us posted on your results.
     
  6. Bill Maylor

    Bill Maylor Well-Known Member

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    I called Zeiss today, to try and get some written info on the Z-Plex. their were very helpful.they are sending me the info I need. They also gave me a co. named www.kentonindustries.com. This co. makes custom drop target knobs for lot of scopes with yardage on the knob. Too easy:). Just wanted to pass along some info if it will help anyone. Thanks again Bill Maylor.
     
  7. royinidaho

    royinidaho Writers Guild

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    Bill,

    Good information.

    Me thinks you'll also need a method to compensate for altitude, shooting angle and atmos changes.

    Justa tho't