What do your drop charts look like?

Discussion in 'Long Range Hunting & Shooting' started by AJ Peacock, Apr 13, 2009.

  1. AJ Peacock

    AJ Peacock Well-Known Member

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    Guys,

    I have spent a lot of time formatting/re-formatting drop charts. Here is what I've come up with. Just thought I would share and see what others have come up with.

    First of all, I use Nightforce scopes with the R1 reticle (which has 10MOA marks above the crosshair and 20moa marks below the crosshair).

    I decided that instead of using a set of given yardages and listing the MOA drops, I'd use a set of given MOA's (from 10moa above to 20moa below the crosshair) and list the appropriate yardages.

    I then wanted to be able to use the chart at a number of different elevations, as a single day of hunting in Southern Colorado can easily require shots from 7000ft elevation to well over 14000ft !!

    Here is what I came up with. With a simple Barometric pressure gauge, I can determine which line of the drop chart to use. If the pressure is between 2 of the lines, I've found that simply estimating between the 2 lines gives me VERY close info as compared to exbal on my PC.

    So far, the drop chart has worked very well. As an example, the cell that is highlighted shows that for a barometric pressure of 22 (approximately 7902ft elevation) and a range of 1240yds , I would use my 12moa below the crosshair and would allow 3.5moa for a 10mph full value wind.

    [​IMG]

    Let me know what you think.

    AJ
     
  2. Buffalobob

    Buffalobob Writers Guild

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    I use a simple laminated piece of paper with an average trajectory for where I think I will hunt. I also include Mach or velocity and TOT being as I might be tempted to take an exceptionally long shot or God send ATH to flame me but I might shoot at something on the move. :D At the bottom of my chart I have the conditions it was run for and the correction factor for alternative conditions. Plus a separate piece of paper for cosine corrections
    This is what appears at the bottom of my 7AM chart for Idaho elk hunting.

    Ele=5175, Temp = 60F

    @1000 yards, +10 Degrees = 0.1 inches less drop
    +1000 ft elevation = -0.2 inches less drop
     

  3. Michael Eichele

    Michael Eichele Well-Known Member

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    I print mine to include the average altitude I will be hunting at as well as the average temprature. It also has equasions and constants for calculating the angle of fire correction.

    This is of course as a last resort when my hand held takes a dump.

    I also cut out the circle for my scope flip cover and tape the range card to my stock. All are printed on waterproof map paper so they do not need lamination.

    [​IMG] [​IMG]
     
    Last edited: Apr 14, 2009
  4. Bravo 4

    Bravo 4 Well-Known Member

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    AJ,
    I couldn't get the pic to come up on the email you sent...but now I see!
    I think you did a hell of a job on it...like you said, you think too much! :D
     
  5. AJ Peacock

    AJ Peacock Well-Known Member

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    Yep, A couple things I failed to mention.

    1) I use a PDA and this chart would only be used in the event that the PDA was not avail.
    2) I wouldn't carry the entire chart, just 3 colors that are centered around the Baro pressure I expect. This makes it small enough to easily tape to the stock of the rifle.

    AJ
     
  6. AJ Peacock

    AJ Peacock Well-Known Member

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    Michael,

    I love your chart. I assume that is the calculator you put together?

    Is there an easy way to output the data from your calculator by MOA instead of by yardage? In other words, list the drops associated with a reticle (like the NF NP-R1)? I currently have to go through all the exbal data and manually create my drop chart for each moa from -10 through +30moa.

    AJ
     
  7. 3fingervic

    3fingervic Well-Known Member

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    Just getting started, and that was some good info.
     
  8. Michael Eichele

    Michael Eichele Well-Known Member

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    Thank you AJ. Yes that is one of the calculators I have put together.

    It is set up for inches, MILS, NP-R2 Bars or clicks.

    I am not 100% sure what you are asking but if it is set up for NP-R2 bars it simply tells you that at a given yardage or in meters how many bars you need for a hit.

    An example is when setting up for a shot at 1000 yards and set for bars, it will tell you you need 9.81 bars instead of 5.7 mils etc.....

    Below is an example. The screen shot is only to 700 yards but you get the idea.

    [​IMG]
     
  9. AJ Peacock

    AJ Peacock Well-Known Member

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    Actually, close but not quite. What I need is the output that shows the bar and the yardage for that exact MOA.
    Like this (moa and yardage from 10 above the crosshair to 30 below) (I use the NP-R1)

    10.....100
    9.......211
    ...
    0.......735
    ...
    -30.....1812

    AJ
     
    Last edited: Apr 15, 2009
  10. Michael Eichele

    Michael Eichele Well-Known Member

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    It has not been assembled that way.
     
  11. sscoyote

    sscoyote Well-Known Member

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    Just a small suggestion here. I also put my dope for the most common air density in my Butler Creek scope cap ocular cover for the reticle i'm using. Any additional information i may need goes into a Butler Creek Blizzard style objective cover. The clear plastic piece is held in place by a spring clip. If u pull that out, the plastic piece comes out and u can put a lot of dope on a sticker and attach it to a thin piece of circular cardborad and put it all back in the BC so when it pops open it's right there to see without having to get out of position to reference it. I have also found that the Blizzard holds onto the scope tube better when switched to a std. BC scope barrel mount. The one that comes with the Blizzard is too flimsy, and tends to slip off when it gets hot out.

    That's a lof of info AJ--well thought out!