Will GPS elevation work?

Discussion in 'Rifles, Bullets, Barrels & Ballistics' started by rdc, Sep 5, 2007.

  1. rdc

    rdc Active Member

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    I'm tired of searching, read the pinnned altitude vs barometric above and I have no way to test ambient pressure vs altitude corrected from barometric sea level(STP metrics)

    Can I get by using altitude correction up to 600 yards or will I miss? 2-4" of error will cause a miss. That $32 La Cross wind meter/temp is calling me. And did I mention I'm cheap.
     
  2. Buffalobob

    Buffalobob Writers Guild

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    Depending upon your bullet and cartridge, a thousand foot elevation change will cause about a half inch of difference at 600 yards.

    The way to prove this to yourself is to run your ballistics program once with one set of data and then change the altitude by 1000 feet while leaving all other factors the same.
     

  3. rdc

    rdc Active Member

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    Okay. Found out my software will not correct for elevation.

    With reference to altitude vs. ambient pressure. Can I get by with a GPS instead of purchasing a Ketrel 2500 at my personal max of 600 yds?
     
  4. ol mike

    ol mike Well-Known Member

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    I'd say -yes -gps elevation is supposedly accurate.

    I stood at a bronze plaque put there by USGS and my gps was a couple of feet off according to the elevation.
     
  5. Jeff In TX

    Jeff In TX Well-Known Member

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    RDC,

    Altitude is not the best means of measurements but out to 600 yards the margin of errors is very small. Barometric pressure is the best means, but it's not always that simple... well it's pretty simple?

    I have a Krestel 4000 weather meter that I use and each time I head out to the range I have to check my local area conditions and calibrate the unit for the current and known barometric pressure. With the internet this is a quick and simple process and it takes less than a minute to calibrate my Krestel.

    Best of luck.