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  1. #21
    Tagging in

  2. #22
    For those using MILS, itís even easier to use a fast wind formulas with G7 BCís in the .3 range, and velocities of 2700-3000FPS, Using your Ballistic calculator (with confirmed drops) off, determine the FV wind speed that will give you a 1 MIL hold at 1000 yards. Be sure to turn off spin drift At ranges less then 1000 yards, the MIL hold in tenths will be equal to the actual yardage.

    This formula with a 6 MPH FV Wind, works quite well(within .1 MIL) for both my 6.5x47 at .287BC/2890FPS, and my 6,5x284 at.313BC/2995FPS)
    At 1000 yards my 6MPH correction is 1 MIL, at 900 yards .9MIL, iat 800 yards is .8MIL..........100 yards is .1MIL. Once this 6MPH distance setting is determined, itís easy enough to cut the setting in half for a 3mph wind , or double it for a 12mph wind( ie. 1MIL at 500 yards).

    i have had excellent success using this formula in competition with my MIL based PRS rifle. Itís fast and easy.

  3. #23
    One of the reasons the MIL wind method you described is so easy to use, is that it assigns a "basic wind" to your gun. In the MIL method, it is whatever wind pushes your bullet 1 MIL at 1000 yards. This breaks down to 0.1 MIL per 100 yards, as we have said.

    We are essentially multiplying the yard line by 0.1....( 800 yards is 8 x 0.1= 0.8). So we set the angle, and adjust the wind to match. The wind then is our constant.

    By applying the same methodology to MOA, we might find the wind that moves our bullet 3MOA (yard line x 0.3) or 5MOA (yardline x 0.5) or 10MOA (yardline x 1).

    For something like a 6.5 Creedmore the "basic wind" for the 3MOA would be a 6mph wind.....for the 5MOA, a 9mph basic wind....for the 10MOA, an 18mph basic wind.

  4. #24
    Other suggestions or comments?

  5. #25
    Taggin in.....
    Philippians 4.20 "To our God and Father be glory for ever and ever. Amen."

  6. #26
    Quote Originally Posted by Meangreen View Post
    Other suggestions or comments?
    Yes...for the mil brake down how do I figure out what wind will offset my bullet by 1 mil at a 1000 yrds?

  7. #27
    You can use a ballistic app on your phone, or go to JBM Ballistics online, it is free.

  8. #28
    Senior Member
    Join Date
    May 2013
    Location
    North Idaho
    Posts
    394

    For shots 800 and under we start with the full value at what ever distance we are shooting. Full value being a 10mph wind from 90 degrees (3 or 9 oclock). Then we continue by reducing in halfs from there depending on actual wind speed and direction. We use a ballistic program to determine full value. For example. At 800 yards with one of my rifles, both bullet flight and the g7 rangefinder tell me that the full value is 4 moa. If the wind is coming from 6 or 12 oclock, no wind correction necessary. ( other than we use .5 moa for spin drift at 500 and 1 moa for spin drift at 1000). If the wind is only 5 mph cut the full value in half. If the wind is coming from any direction other than 3, 9 6 or 12 we cut it in half again. Back to the example. Full value is 4moa. Wind is 5 mph, so now we are working with a value of 2. Wi nd is coming from 3 or 9, use 2moa. Wind is coming from 1,2,4,5,7,8, 10, or 11, cut the 2 in half again and use 1moa. After a learning curve this can be fine tuned, where we give more value to say 2 and 4 than we would say 1 and 5. And you can fine tune the wind portion by giving more value for 5-9 plus mph and less value for 1-4 mph This isnt perfect but works really well out to 500-600 without the fine tuning, and with fine tuning out to about 800 or so. Before long with practice , out to around 800 or so, you will begin to make calls by feel. If we are shooting an elk at 800 yards, we will feel the wind at location, read it through a spotting scope at target, and make a quick call by feel based on practice. Anything further than 800 we study the wind and input our best educated wind speed and direction into our ballistic program, and let it tell us what to dial. The program takes shot angle, spin drift and coriolis Into consideration.
    Last edited by lamiglas; 04-05-2019 at 19:03.

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