DROP CHART . When EXBAL FAILS ???

Discussion in 'Long Range Hunting & Shooting' started by bigbuck, Dec 28, 2012.

  1. bigbuck

    bigbuck Well-Known Member

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    How do you guys go about creating an accurate or average hard copy drop chart ? I see some of you have them taped to your rifle stocks in some photos ? I usually enter real world conditions with my Kestrel as I know elevation baro, temp,RH changes from location to location and day to day . So how do you get say a rough estimate as accurate as possible ? Thanks any help will be appreciated ..........
     
  2. angus-5024

    angus-5024 Well-Known Member

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    I use my most likely conditions during hunting season. Where I am its usually between -5*C and +2*C and I usually am hunting between 2500 and 3500 ft. with a R/humidity of 30-50%.
    My conditions would be 0*C,3000 ft. and 40% RH. baro around 28.8

    put that on an excel spreadsheet and away you go. Then make a correction in MOA per 10*C and for every 1000 ft. I also have a picture of my reticule and the drops for that on the same sheet.

    I will only use a drop sheet to 700 yards, after that I'm only comfortable with a PDA/phone.

    Oh, if its not gonna get taped to your rifle, carry like 6 of em throughout your pack.
     

  3. toddc

    toddc Well-Known Member

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    I calc a corrected altitude diff per 1000 and put that next to windage at 10mph and do it in my head out to 1200 on my charts. Prefer a phone or palm past 800 but I just have a feel for it also kinda like windage.
     
  4. joseph

    joseph Well-Known Member

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  5. toddc

    toddc Well-Known Member

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    Do you fudge the corrected altitude with that turret? If your conditions are way off how do you allow for it? I was thinking of simplifying with a turret and a fudge factor for various conditions is this what you are doing to account for varying corrected altitudes?
     
  6. joseph

    joseph Well-Known Member

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    I did the drop chart where I live in North Georgia ( el. 800 ft. ) and when I ordered the custom turret I told Vortex I wanted it for hunting in North East Wyoming and they adjusted the altitude to 4,500 feet and everything else to match the arc. I wanted the turret to be true to follow the arc of my bullet as it goes down range. Vortex adjusted all the figures for the computer so the turret would be right on the money. They did a perfect job because when I was at a 2,000 yd. range up there I shot from 200 yds. all the way out to 900 yds. which is as far as my turret is marked for. It was dead center at every 100 yd, interval out to 900 yds. :):):):)

    Back here in Georgia the arc is the same out to 400 yds. Past there the turret will probably be farther off because of the difference in elevation.

    joseph

    PS: When I shot 1,000 competition I had to count 108 MOA clicks up from my 200 yd. zero. which put me centered in the 1,000 yd. target. All three 5 shot groups would have hit in the boiler room of an antelope. :D
     
  7. WildRose

    WildRose Well-Known Member

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    Verify your drops and known ranges, and adjust your BC or velocity or both until you get a match on your calculator.

    Print those drops.

    If you can do it at different elevations conditions and make up multiple cards.

    One thing you can count on with technology is that it's only likely to fail you when you need it the most so always have a backup plan.

    As stated above if you go with custom turrets you can get them for different bullets, different elevations/conditions.

    While we try to narrow the variables and unknowns as much as possible for precision with the high speed calibers we are shooting today combined with the high BC bullets a change in conditions (other than wind) usually isn't going to make or break you out to 1,000yds.

    Beyond 600yds, life gets complicated but controllable, beyond 1,000yds, life gets extremely complicated so you want everything as exact as possible.
     
  8. joseph

    joseph Well-Known Member

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    One thing I do is always shoot the same bullet weather I'm shooting prairie dogs or whitetail deer. This takes another variable out of the picture with a custom turret.

    joseph
     
  9. joseph

    joseph Well-Known Member

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  10. 4xforfun

    4xforfun Well-Known Member

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    Everything I need to know out to 1500 yards.
    Dial up's in MOA every 25 yards.
    Wind dope in MOA every 100 yards with wind speeds from 5 to 30 mph
    NP-R1 retical holdover chart.
    All set for my hunting elevation and within Plus or minus ten degrees f of the temp.

    I usualy have my Shooter program and Kestral 3500 with me...but not always.
     

    Attached Files:

  11. Joe King

    Joe King Well-Known Member

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    I do the same thing, JBm balistics has a handy drop card that allows you to have up to 3 sets of variables on 1 range card, printed out their not very big either. Laminate it, fold it up and stick it the pocket of this
    MidwayUSA Rifle Cheek Rest Rifle Ammo Carrier 5-Round Fixed Stock
     
  12. Greyfox

    Greyfox Well-Known Member

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    I have used yardage turrets for the past several years now. While I have turrets for the locations and typical conditions, I also have committed to memory click adjustments for relevant temperature and altitude variations in a given location which is1-2 clicks for each 1000 ft or 15 degree change depending on distance. This has worked well and is fast. This past season I used a G7 rangefinder that compensates and gives a yardage correction for any turret program I enter. It works so perfectly and I so fast it almost feels like I'm cheating. For back up I always have my Geovids and traditional equipment and technique. Since my yardage turrets limit out at 1000 yards which is my limit on game, if I want to shoot targets or coyotes at longer ranges, I switch my turret to MOA, or will just use come-ups from the 1000 yard mark on my turret. I like the idea of the turret from G7 Nightforce from Gunwerks that has both yardage and MOA on the same turret. I just mounted one on a 338 I'm working on but haven't had a chance to set it up and use it yet.
     
  13. albertakid

    albertakid Well-Known Member

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    Rea: DROP CHART . When EXBAL FAILS ???

    I have been using a prototype I developed that makes field range cards a lot easier to read and use still looking for the best way to show it to the public and not get hosed out of my idea
     
  14. bigbuck

    bigbuck Well-Known Member

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    Thanks guys for your help . My exbal hasent failed me yet but I would hate to have that perfect long range shot standing broad side no wind an the battery go down on the Dell Axium :rolleyes:

    Thanks again for your response.