alltitude

Discussion in 'The Basics, Starting Out' started by zach93, Jan 14, 2008.

  1. zach93

    zach93 Member

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    I live at 50 feet above sea level I go hunt wyoming every year for deer and antalope my question is if I set my gun up to shoot here for deer hunting then go to wyoming where it is 4500 feet how will this affect the bullet. will I have to switch the dials, change impact and that whole thing.
    I have not got the dials or anything to start.
    Just asking questions before I start.

    Thanks,
    Zach
     
  2. J E Custom

    J E Custom Well-Known Member

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    Zach

    The higher you go the thiner the air.

    The bullet will impact higher if the temp and humidity are the same as
    at sea level.

    The best thing to do is plan on sighting in at a minimum of 3 different
    yardages (100,300 and 500yrd,s to establish your trajectory at that
    elevation.

    J E CUSTOM
     

  3. Buffalobob

    Buffalobob Writers Guild

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    The best thing to do is use JBM Eskimo and enter all of your data from where you normally shoot and record that information. Then go back and change the altitude input to what you hunt at in Wyoming. Take note of the difference.


    For one of my rifles, these are the affects of temperature and altitude on the point of impact.

    Effects @1000 yards
    10 Degrees F = 0.1 inches of drop
    1000 ft elevation = 0.2 inches of drop

    So if my drop chart or dial was established at sealevel and I hunted at 5000 feet ( 5 X 0.2 = 1.0) I would be off by exactly 1.0 MOA at 1000 yards which is 10 inches or more.

    Temperature changes can be computed similarly.
     
  4. J E Custom

    J E Custom Well-Known Member

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    Altitude

     
  5. Sendero_Man

    Sendero_Man <strong>SPONSOR</strong>

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    Zach,

    what are you shooting ?

    Rifle, load data, velocity, zero... etc.

    thanks
     
  6. Buffalobob

    Buffalobob Writers Guild

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  7. J E Custom

    J E Custom Well-Known Member

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    Sorry BOB

    I use the JBM all the time, It was the (ESKIMO) that threw me off.

    Thanks
    J E CUSTOM
     
  8. zach93

    zach93 Member

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    Right now I just got all my reloading stuff last couple of weeks.
    I am shooting a tikka t3 lite ss in 270 wsm With leupold VX-II 3-9X40 the barrel is kind of medium contour.
    How much will a bedding job help out at long range I dont know how to bed a rifle so if I do decide to bed my gun how hard is it?
    Getting ready to buy dies then I will find out what bullet I want to shoot.
    I am thinking of shooting either the nosler ballistic tip, hornady interbond, sierra match king, maybe try the swift scricco anybody have any experiance? the factory bullet I am shooting now is the federal premium nosler accubond 140 gr and it is shooting terribale 2.5-3.25 in groups.
    I want to be able to shoot out to 500 yards minimum maybe 700.
    also what kind of bipods are you guys using.
    Thanks for all the help.

    Zach
     
  9. Sendero_Man

    Sendero_Man <strong>SPONSOR</strong>

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    Here is an example of the 2 different states.

    load data used was a Federal Vital Shock 270 WSM 140 grain nosler accubond. 3200 fps

    With a 200 yard zero, you'd be good out to 400 yards in both states.

    Home state data:

    based on 50 ft. asl and 70 degrees.

    RANGE Elevation
    (yd) MOA
    0 0.00
    50 -0.50
    100 -1.00
    150 -0.75
    200 0.00
    250 0.75
    300 1.75
    350 2.75
    400 3.75
    450 5.00
    500 6.25
    550 7.50
    600 8.75
    650 10.25
    700 11.75
    750 13.25
    800 15.00
    850 16.75
    900 18.50
    950 20.50
    1000 22.50


    And here is the Wyoming data:

    based on 4500 ft asl and 40 degrees

    RANGE Elevation
    (yd) MOA
    0 0.00
    50 -0.50
    100 -1.00
    150 -0.75
    200 0.00
    250 0.75
    300 1.75
    350 2.75
    400 3.75
    450 4.75
    500 6.00
    550 7.25
    600 8.50
    650 9.75
    700 11.00
    750 12.50
    800 14.00
    850 15.50
    900 17.25
    950 19.00
    1000 20.75
     
  10. zach93

    zach93 Member

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    Thanks,
    Is there a diffreance in tempeture bucause 2 years ago is ranged around 25-35 dergrees in wyoming and in california deer season its 90-100 degrees in aug. and 75-85 in sep. is that going to change the whole chart?
    Zach
     
  11. Buffalobob

    Buffalobob Writers Guild

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    First of all, the gold standard of bipods is the Harris with the notched legs and swivel base.

    Secondly, when you get ready to bed the rilfe which is a good beginners gunsmithing job, just put up a post on how to bed a rifle. Somewhere is a very detailed and comphrehensive thread on it but the "search" function usually doesn't find it for some reason. You have to know what you are looking for. I really like it because it is so detailed.

    Rifles are like people, each has its own personality and will only enjoy eating certain foods. It doesnot matter what you like. It only matters what the rifle likes. That is one reason many of us reload - to try to coax the rifle into shooting what we like.

    I do not shoot a 270WSM so I am not going to try to guess what it will like.
     
  12. Sendero_Man

    Sendero_Man <strong>SPONSOR</strong>

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    If you look at the charts I did...

    Home is 70 degrees

    and Wyoming is 40 degrees.... :)