Zero in for long range shooting

Discussion in 'Long Range Hunting & Shooting' started by WizardM, Oct 1, 2011.

  1. WizardM

    WizardM Active Member

    Messages:
    43
    Joined:
    Aug 25, 2008
    I'm using a Remington 700 Laminate Thumbhole Special Run 300 WSM with Nightforce NXS 5.5-22x56mm scope. My local shooting range is only setup upto 200 yards. I want to be able to shoot to 600 to 800 yards, and eventually to 1000 yards. How should I zero in my scope for it? It's shooting at 2" high bullseye at 200 yards target now. Should I do anything in order to get bullseye say at 600 yards or 800 yards?

    Looking for input from seasoned LR shooters. Thanks a lot.

    gun)
     
  2. T3-OleMan

    T3-OleMan Well-Known Member

    Messages:
    638
    Joined:
    Jan 3, 2009
    Your Ballistics Calculator might require you to be Zero at 200YDS. My ZEISS does.
     

  3. Pons

    Pons Well-Known Member

    Messages:
    124
    Joined:
    Mar 13, 2011
    You could use a ballistics program like Berger's or JDM to model your bullet drop and flight path

    Berger Bullets

    JBM - Calculations

    Do you have a chronograph?

    -Pons
     
  4. Sendero_Man

    Sendero_Man <strong>SPONSOR</strong>

    Messages:
    1,706
    Joined:
    Feb 4, 2007
    I would zero for 200, chronograph your load, make your drop chart to get you started with your drops at longer ranges, then... you need to shoot at those ranges and confirm your drops.

    You might have to then go back to your software and tweek your FPS or the BC of the bullet to match your actual drops. Target validation is very important ~!!

    Also, you need to consider spin drift, wind direction, wind speed... and many other factors when shooting at longer ranges.....

    Practice, practice and more practice
     
  5. WizardM

    WizardM Active Member

    Messages:
    43
    Joined:
    Aug 25, 2008
    Thanks all for the input. It seems there are a lot of gadets you need to bring

    to the field in order to get accurate shooting at any long distance. Which

    ballistic program, calculator, wind reader do you use on the field? What other

    obsolutely necessary gadgets do you carry with you? I would love to hear

    from you.
     
  6. WildRose

    WildRose Well-Known Member

    Messages:
    8,210
    Joined:
    Feb 3, 2011
    Actually no the toys are not necessary, but they sure take out a hell of a lot of guess work.

    If you just take a range finder with you, a drop and wind chart, and get yourself some practice particularly at things like reading the wind you can get to 1000yds very easily.
     
  7. WizardM

    WizardM Active Member

    Messages:
    43
    Joined:
    Aug 25, 2008
    No, I don't have a chronograph. Which program do you use? Is it better to have one for filed use? Is it essential to use chronograph?
     
  8. WildRose

    WildRose Well-Known Member

    Messages:
    8,210
    Joined:
    Feb 3, 2011
    No you chronograph your loads to see how fast they actually run so you can get the most accurate results possible from a ballistic calculator.

    Just going off of reloading charts and the velocities they give may have you 100 or even 200fps off from the actual velocity.

    No you don't need one to take hunting, but if you are going to dope and dial using output from a ballistic computer program you do need the most accurate data possible to plug into the program to get the best results.
     
  9. Pons

    Pons Well-Known Member

    Messages:
    124
    Joined:
    Mar 13, 2011
    I would not use a chronograph in the field. I would (and do) use one when I am putting together loads and sometimes during target practice to see if I start to get any unexpected changes in bullet velocity.

    A chronograph is nice for getting you better data to model your bullet flight with. If you do not have one, you can use your published "muzzle velocity" for your ammo. Then, just have a really big target at further range to see where your bullet hit vs. expected.

    Lets say you used Federal factory ammo with a 180 gr accubond with a estimated (from factory) muzzle velocity of 2960 fps. G7 BC for the 180 accubond would be 0.246 (0.246 G7 BC from Applied Ballistics - by Bryan Litz). You can plug those values in to (lets use the Berger model for this one) along with the height of your scope center above the center of your bore, along with atmospheric conditions ( temperature, humidity, pressure ) to give you an estimation of what your bullets flight path would be.

    You have errors, always. So, when you are out practicing at 600 yds, you can use the estimates from the model to get an idea of how low you might be. Then you shoot at your target and then "dial in" to find out what your setting should be.

    Hypothetical - if your load is similar to the one mentioned above, and you are 2 inches high at 200 yds, you are probably sighted in somewhere around 250 yds. On std atmospheric conditions day, you might be around 5 feet low at 600 yds. The thing is, you need to test out your estimations on targets at 600 yds. It would be good to test at 300, 400, 500 as well. The further you get out, the more important it is for you to know how far the target is and the larger 1 moa scope adjustment matters. If your scope (nice choice btw) is right on with minute adjustments then 1 moa at 100 yds is 1.0471996" inches, at 300yds it is around 3.14", at 600 yds, it is around 6.28". At 600 yds, with the previously mentioned Federal load, if the distance is 25 yds closer or further away, the height adjustment is going to be about 1 moa (based on estimation of being sighted at 250 yds with 1.75" scope height). Therefore, if you see a target at 600 and you think it is 625, on a std day, you would be around 6 inches high. Lets say then that you saw it at 630 yds, you thought it was 575 yds, you would be around a foot low. Of course, all that doesn't take into account how precise your shooting rig & you are. (ie add more error)

    That is all based on the assumption that your load met the criteria entered every time with no variation (not real life - there will be some fps difference). If you are shooting instead around 2880 fps, and still shooting 2 inches high at 200 yds, well then you are probably sighted a bit closer than assumed earlier. Everything will change some. Modelling, is based off the info you put in.

    That is something nice about a chrono. It lets you know while you are practicing of what your velocities are (albeit with some error), and if you are getting a wide variation in velocities.

    If you don't have a smart phone, pda, or some ballistics computer with you, you can print out ballistics charts for your loads and expected conditions to give you a guideline.

    I haven't even mentioned wind, angle, bullet spin, etc...

    Good range estimation is very important. Laser range finders and gps and maps, using your mil-dots are methods of getting a range estimation. You need have good range estimation, unless you are sighted in at a fixed target have been consistently hitting said fixed target, and your game animal also comes to and stands immediately in front of that fixed target. :)

    Toys are great both for giving you good data and helping you improve your estimations, nothing replaces practice. Hit some paper and gongs at different long ranges, get consistent at it.

    A great book for you to read would be "Applied Ballistics For Long Range Shooting" by Bryan Litz. He has a good Ballistics program for smart phones - Products

    I use Bryan's ballistics programs.
     
    Last edited: Oct 2, 2011
  10. Pons

    Pons Well-Known Member

    Messages:
    124
    Joined:
    Mar 13, 2011
    I agree with WildRose
     
  11. WildRose

    WildRose Well-Known Member

    Messages:
    8,210
    Joined:
    Feb 3, 2011
    Yep and if you are dinosaur like me who doesn't use a smart phone you can pick up a good, used Rugged PDA off of Ebay for anywhere from about 200.00 up to use specifically for field ballistics calculations.
     
  12. WizardM

    WizardM Active Member

    Messages:
    43
    Joined:
    Aug 25, 2008
    Wow, thanks for the great posting. Your knowledge really enlights me. There are so much I need to learn for LR shooting. I'm going to check out the book "Applied Ballistics For Long Range". I do have Perry's Exbal program for my HP iPaq PDA. Haven't try it out on the field yet. I guess I need to get a wind meter like Krestel 4000. Thanks a lot!
     
  13. Pons

    Pons Well-Known Member

    Messages:
    124
    Joined:
    Mar 13, 2011
    Thanks, glad you liked it. I hope you have lots of fun & good shooting :)

    -Pons