Calculating mph rifle

Dunraven

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At a recent match, many on my squad were describing their wind calls in terms of mph, by saying eg: I used a 5mph wind( rather than describing it in terms of mils). These were good shooters doing this. (I just got on their squad by accident). Where can I learn about this technique, and whether it is a better way, or just a different way?
 
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    That is a method we talk about a lot




    Go into the Everyday Sniper Podcast Section it's there a bunch

    Basically you determine your 600 yard wind so it lines up to .6 Mils at 600

    That is your MPH Gun, so you have

    100 = .1
    200 = .2
    300 = .3
    400 = .4
    500 = .5
    600 = .6

    From there you only use multiples of that MPH
     

    Sheldon N

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    At a recent match, many on my squad were describing their wind calls in terms of mph, by saying eg: I used a 5mph wind( rather than describing it in terms of mils). These were good shooters doing this. (I just got on their squad by accident). Where can I learn about this technique, and whether it is a better way, or just a different way?

    Speaking wind holds in terms of MPH is an easy way to allow shooters to share wind calls without worrying about whether they are shooting a gun with the same ballistics. One shooter might have a 110SMK at 3050fps and another might have a 105 hybrid at 2850 fps. They can't use the same wind hold because the guns have very different wind drift.

    If I shoot a stage and for the long target I was holding 1.1 mils, I know from my ballistic solver what that worked out to in mph because I had to input mph into my solver to get a wind hold. I might have guessed the wind was 6mph, but that wasn't enough wind hold, I corrected and got hits with the hold that matched up with my 8mph dope. I'd walk off the stage and tell my buddy that 8mph hold was getting me impacts. He can then look at his dope and use whatever mil hold matches up with 8mph, regardless of whether his ballistics are the same.

    Of course, once he has my wind call he misses because the wind changed and did something totally different and he should have been paying attention to the conditions rather than what I was holding. :)

    Side note, the term calculating a "mph gun" is something different. That has to do with being able to quickly estimate a wind hold without having a ballistic solver do it for you.
     

    Dunraven

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    That is a method we talk about a lot




    Go into the Everyday Sniper Podcast Section it's there a bunch

    Basically you determine your 600 yard wind so it lines up to .6 Mils at 600

    That is your MPH Gun, so you have

    100 = .1
    200 = .2
    300 = .3
    400 = .4
    500 = .5
    600 = .6

    From there you only use multiples of that MPH
    I believe this is what i'm looking for. having trouble following those videos you sent. can't find 'everyday sniper podcast section'. what is the first step in determining a 600 yard wind? if a kestrel is used, isn't that telling you what you need to know? it gives wind values with corresponding corrections. apologize for my ignorance. just trying to put these things together.
     

    MinnesotaMulisha

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    I believe this is what i'm looking for. having trouble following those videos you sent. can't find 'everyday sniper podcast section'. what is the first step in determining a 600 yard wind? if a kestrel is used, isn't that telling you what you need to know? it gives wind values with corresponding corrections. apologize for my ignorance. just trying to put these things together.

    In your ballistic calculator, enter all of your data. Velocity, bullet, zero yardage etc.

    Then enter in wind values at 90 degrees to the bullet path.

    Change wind values until, as @lowlight noted, your wind hold at 600 yards is .6 mils.

    If that is 4 mph, you have a 4 mph rifle, or actually a 4 mph load.
     
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    Dunraven

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    In your ballistic calculator, enter all of your data. Velocity, bullet, zero yardage etc.

    Then enter in wind values at 90 degrees to the bullet path.

    Change wind values until, as @lowlight noted, your wind hold at 600 yards is .6 mils.

    If that is 4 mph, you have a 4 mph rifle, or actually a 4 mph load.
    that gives me a 7mph rifle or 'load'. how do I use that in a match?
     

    Jack Master

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    how do I use that in a match?

    So when you are at a match:
    Step 1
    - Measure the true wind speed and angle. Example - the true wind is blowing at 20mph at 45 Degrees (1:30 o-clock right to left wind).
    Step 2 - Turn the wind speed to a 90 deg full value. Example - Using a wind rose or trigonometry the portion of the wind vector that is at 90 Degrees to you is 14mph.
    Step 3 - get your wind hold by using your MPH. Example - 600 yard target is 0.6 mils at 7mph, so at 14mph is it 0.6x2 = 1.2mils wind hold.

    The beauty of using the mph method is the corresponding holds at other distances. For your 7mph gun here are your holds at 7mph in a corrected wind.
    100 yds = .1
    200 yds = .2
    300 yds = .3
    400 yds - .4
    500 yds = .5
    600 yds = .6
    and so on. Around 800 or 900yds is might skip a extra tenth 800 = .9 and skip another at 1000 or 1100. You'll have to check your data to know when your gun will skip a tenth.

    Match Example
    Target at 400 yards
    True wind = 10mph wind at 5PM (R to L)
    Vector = 5mph wind (from wind rose)
    Hold is .4 at 7mph - so hold at 5 mph = .3 (this is rough math that can be quickly done in the field)

    Please note - when finding your gun mph you must use the Wind value only. No spin drift, no Coriolis, no alien voodoo. Just pure wind. If your shooting more than 1000 yards or more you can then add the voodoo stuff manually.

    Cheers.
     
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    Sheldon N

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    that gives me a 7mph rifle or 'load'. how do I use that in a match?

    IMO you wouldn't. You have plenty of time for stage prep. There's no reason you couldn't look at your kestrel and figure out your wind call for the exact yardage at different mph options, rather than doing rough math in your head. It gets to be too much otherwise. You have targets at 376 yards, 581 yards, 731 yard and 1045 yards, wind quartering in from 10:30 gusting and lulling from 3mph to 8mph. Too much math to do in your head on the fly, which is why people write out dope cards with elevation and wind holds.

    What people do in standard PRS/NRL matches is what I described in my post above. Where you would use this is a hasty shot in the field where you don't have time for fumbling with calculators, like maybe a hunting scenario or one of the field based hike, find targets on the clock, range then engage matches.
     

    lowlight

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    Nah, it works perfect, it's not hasty

    and let' s be honest, there is no wind strategy in PRS/NRL, it's edge of plate and adjust ... very few do it right in a match

    Once you know it's lined up in your Ballistic Calculator, you can use it, but at the same time, you know your wind is now trued like your elevation.

    Understanding how to use it is different from guys playing a game with wind cheater calibers, (7MPH is sporty, closer to a 338 in numbers) so most of these guys are just holding edge.

    That is why in my stage recently nobody cleaned it even though it 680 yards to the farthest target and 2 out of 3 were full sized IPSC Plates, but we had wind, and so people blew the first two shots trying to figure it out. See this everywhere, the strategy is correct off the first shot.
     

    Sheldon N

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    Shot maybe a dozen matches thus far this year, most in locations where holding inside of plate edge would be considered an unusually calm day. Probably been squadded with 100 different people. Can't say I've seen or heard anyone using this technique in a match. I know many guys are aware of it, consider it valuable and have it in their mental toolbox. Not belittling the technique, just saying it's not what most guys are using in matches.

    OP... in your original post you described exactly how people shoot in matches.

    At a recent match, many on my squad were describing their wind calls in terms of mph, by saying eg: I used a 5mph wind( rather than describing it in terms of mils). These were good shooters doing this. (I just got on their squad by accident). Where can I learn about this technique, and whether it is a better way, or just a different way?

    The confusion stems from the fact that you used "mph gun" in the title of your post, which has nothing to do with what you described. Two separate things.
     
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    lowlight

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    I was the RO, so I saw it ... and with the Podcast we have been paying a lot of attention to wind strategies, both myself and Mike M have been looking at it and sampling shooters

    You may have gotten lucky with your squad
     

    PracticalTactical

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    I first make a basic wind deflection table for my ammo.

    Determine the wind deflection in mils or MOA (your choice) for a full value 5 MPH wind at different distances… like every hundred yards.

    This basic table provides all I need to make the adjustment on the range, because its easy math at that point.

    I see a 10 mph wind from 3 o'clock… double the MOA or MIL value in the table for that distance. (because its twice the 5 mph value in the table)

    I see a 10 MPH wind from 1 O'clock, that’s half value wind… use the 5 MPH MOA or MIL value from the table for that distance.

    If the distance is somewhere in between, just figure about what it would be in relation to the closer and farther values in the chart.

    I made nice printed turret wraps to tape the info right on the scope turret that worked very well for this. Its so simple.

    I just need to do a little bit of in my head interpolation on the fly, that's all. I've never found a faster method.

    If it's taped to the turret, I can get to a point where I don't even think about MILS or Minutes, just the wind value that correlates to the distance.
     
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    Dunraven

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    Thanks much to all. It's slowly coming into focus. Looking at this approach as something that could improve my performance, since these 'good shooters' seemed to be using it.
     

    Jack Master

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    There's no reason you couldn't look at your kestrel and figure out your wind call for the exact yardage

    Unless you are new or cheap and don't have a Kestrel. Sure would be nice... cuz I ain't got one.

    I used this method at a match last weekend, I didn't have any trouble bracketing wind and different ranges or intermediate ranges. And, I was the only shooter in my squad to hit the 1000+ yard target. They all held way to much wind that thier Kestrel told them to use.
     
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    Jack Master

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    a full value 5 MPH wind at different distances…
    I think you missed the boat on the gun Mile per hour idea. Making charts for 5 and 10 mph for distances is the old way. Frank showed us a new faster method (gun mph) this last year. Forget the 5mph and 10mph (I used to do this too) and get on board with the mph method. Its so much easier to remember, faster to use and easy on the brain one you get it.
    What works for you works for you, I get it. No worries there, but I think if you try the mph method you'l really like it. Note - It works best in mils. If you are in MOA than what you are doing might be the best.
     
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    Two ways of doing mph:

    Line it up at 600 yards, and add a 0.1 or so after 800 yards.

    Line it up at 1,000 yards and accept the small deviations at the closer distances where it matters least.

    I prefer the latter, but I don't shoot matches where most targets are 600 and closer.
     
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    PracticalTactical

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    I think you missed the boat on the gun Mile per hour idea. Making charts for 5 and 10 mph for distances is the old way. Frank showed us a new faster method (gun mph) this last year. Forget the 5mph and 10mph (I used to do this too) and get on board with the mph method. Its so much easier to remember, faster to use and easy on the brain one you get it.
    What works for you works for you, I get it. No worries there, but I think if you try the mph method you'l really like it. Note - It works best in mils. If you are in MOA than what you are doing might be the best.

    The problem for me is that I've been shooting MOA forever and I'm not sure how Franks way converts to minutes.

    I had an IOR 3-18 in Mils for a few years but it just slowed down my translation time from minutes, so I sold it. Now for better or worse have to deal with MOA.

    More like this I suppose but not so easy to remember.

    100 yds = 3/8 MOA
    200 yds = 3/4 MOA
    300 yds = 1-1/8 MOA
    400 yds - 1-1/2 MOA
    500 yds = 1-7/8 MOA
    600 yds = 1-1/4 MOA
     
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    Long Range 338

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    The problem for me is that I've been shooting MOA forever and I'm not sure how Franks way converts to minutes.

    I had an IOR 3-18 in Mils for a few years but it just slowed down my translation time from minutes, so I sold it. Now for better or worse have to deal with MOA.

    More like this I suppose but not so easy to remember.

    100 yds = .1 mils x .36 MOA = .36 MOA
    200 yds = .2 mils x .36 MOA = .72 MOA
    300 yds = .3 mils x .36 MOA = 1.08 MOA
    400 yds = .4 mils x .36 MOA = 1.44 MOA
    500 yds = .5 mils x .36 MOA = 1.8 MOA
    600 yds = .6 mils x .36 MOA = 2.16 MOA

    It looks like it would translate really well from mils to MOA with a quick conversion like I did above. I am assuming that you are only able to gauge or adjust for wind in 1/4 MOA increments. Perhaps its that I am used to mils but it seems just as easy to deal with the numbers in decimals and round to the nearest .25 MOA
     

    Dunraven

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    I think you missed the boat on the gun Mile per hour idea. Making charts for 5 and 10 mph for distances is the old way. Frank showed us a new faster method (gun mph) this last year. Forget the 5mph and 10mph (I used to do this too) and get on board with the mph method. Its so much easier to remember, faster to use and easy on the brain one you get it.
    What works for you works for you, I get it. No worries there, but I think if you try the mph method you'l really like it. Note - It works best in mils. If you are in MOA than what you are doing might be the best.
    would you explain it please?
     

    Snuby642

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    The part I am not getting is the 600 yard starting part?

    Is there a reason for the 600 or just an example?
     

    lowlight

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    600 yards is because even with a 308, the wind will line up perfect, after 600 in lesser calibers it will change by .1 mils after. Short answer the bullet is slowing down so the wind has bigger effect.

    With a 7MPH rifle it will not really change until closer to 800 yards.

    600 is the perfect middle ground to line everything up.

    Guys appear to be missing the simplicity that everyone else sees,

    6 MPH Rifle
    100 = .1
    200 = .2
    300 = .3
    400 = .4
    500 = .5
    600 = .6

    It' s simple counting starting from 1, if the wind is stronger you use that same multiple to figure it based on this.

    Your wind offset comes from BC in a calculator, the first number in the G1 BC is your wind speed, so if you are shooting a cartridge with a .605 BC you have a 6 MPH. (there are other factors like atmospheric but that is something else and pretty small)

    A 308 with a .496 BC is a 4 MPH gun, so you now know how the ballistic calculator looks at your bullet in terms of wind.

    We shoot a series of 4" plates at 675 yards during our wind class, normally in winds 12MPH to 18MPH out here and this works perfect, guys hit the plates on command in higher than average winds. In lower winds it's just as easy.

    The random use of 10MPH is silly and does not match anything, it's just a random number, sure the British Method works with MOA using 10MPH but that is based on a 168gr 308 and nothing else. This works with every caliber.

    Using this and the target's error budget you'd hit a lot more often in the wind.
     
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    The problem for me is that I've been shooting MOA forever and I'm not sure how Franks way converts to minutes.

    I had an IOR 3-18 in Mils for a few years but it just slowed down my translation time from minutes, so I sold it. Now for better or worse have to deal with MOA.

    More like this I suppose but not so easy to remember.

    100 yds = 3/8 MOA
    200 yds = 3/4 MOA
    300 yds = 1-1/8 MOA
    400 yds - 1-1/2 MOA
    500 yds = 1-7/8 MOA
    600 yds = 1-1/4 MOA
    The methodology is the same.

    Find the wind that gives you 5moa drift at 1,000 yards.

    This should translate to 1/2 moa per hundred.
     

    Snuby642

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    Just tried that calc and worked out to be 6mph for 6.5g shooting 123 sst.

    Does that sound right.
    Used the moa method.
    @ 2500 fps
     
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    Just tried that calc and worked out to be 6mph for 6.5g shooting 123 sst.

    Does that sound right.
    Used the moa method.
    @ 2500 fps
    When I put your numbers into my solver, I get 5mph giving 5moa at 1k yards @ 2k ft elevation.

    If you are using 600 yds, then 6mph is a good fit.

    That round will go subsonic around 900 yards according to my solver.
     
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    Snuby642

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    Thanks.

    I will have to redo the numbers as soon as my dies get here anyway.
    Just remembered Hornady says 2580 fps in a 16 inch barrel I have a 20 inch.
    Have 80 rnds down it and figure setteled in by now. Time to chrono.
     

    Jack Master

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    PracticalTactical

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    So I punched in the bullet using JBM and a .308 155 SMK 2156 at 2800 FPS being max speed for PRS.

    Using a wind speed of 14 MPH it works out for MOA about as follows...

    14 MPH Wind @ 9 O'clock

    100 Yards=1 MOA
    200 Yards=2 MOA
    300 yards = 3MOA
    400 Yards = 4 MOA
    500 Yards = 5 MOA
    600 Yards = 6 MOA
    700 Yards = 7.5 MOA
    800 Yards = 9 MOA
    900 Yards = 10.5 MOA
    1000 Yards = 12.25 MOA

    It's a little messy because diving by 14 doesn't round very well but its workable.

    How well this works for you would depend on the BC and muzzle velocity rounding off to a base wind speed that's easier to work with.

    I ran the .223 75 grain Hornady ELD at 2900 FPS and it works out about the same for a 13 MPH wind... so it gives up one MPH in wind performance compared to the 308 with 155s.
     
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    So I punched in the bullet using JBM and a .308 155 SMK 2156 at 2800 FPS being max speed for PRS.

    Using a wind speed of 14 MPH it works out for MOA about as follows...

    14 MPH Wind @ 9 O'clock

    100 Yards=1 MOA
    200 Yards=2 MOA
    300 yards = 3MOA
    400 Yards = 4 MOA
    500 Yards = 5 MOA
    600 Yards = 6 MOA
    700 Yards = 7.5 MOA
    800 Yards = 9 MOA
    900 Yards = 10.5 MOA
    1000 Yards = 12.25 MOA

    It's a little messy because diving by 14 doesn't round very well but its workable.

    How well this works for you would depend on the BC and muzzle velocity rounding off to a base wind speed that's easier to work with.

    I ran the .223 75 grain Hornady ELD at 2900 FPS and it works out about the same for a 13 MPH wind... so it gives up one MPH in wind performance compared to the 308 with 155s.
    Use 1/2 moa per hundred (5moa at 1k) it's easier.
     

    PracticalTactical

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    For some reason I've always remembered 1 MPH wind = about 1 MOA at 1000 yards... so working backwards from there this MPH system is pretty close.

    But the real advantage is in communicating a common wind value if guys are shooting different calibers.
     

    lowlight

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    1 MPH at 1000 yards is a 308 only

    You are going back to old stuff where everything is based off a 308, 168 at 2550fps same thing with the USMC Wind formula, based off a specific bullet at a specific speed. You need to change the constant for your caliber and changing the constant requires you already know the wind hold.

    Wind was always voodoo because everyone used flawed data from the start. The wind rose was flawed a 1/2 value wind is not half the value but 1/2 the distance, the formulas were for a specific bullet and did not adjust for the shooter. So the old mantra was, grab a case and go out and shoot in the wind. Expensive and it requires you have the capacity to understand and learn from the misses.

    Here we give you the tools do it for your system with an actual number... it's not a guess, it's an actual adjustment.
     

    Rutter

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    I just need a bit of help here. Sorry for being stupid or slow to understand this. You guys are saying to go off of the G1 bc. With a bc .617, With that being said my 6creedmoor with 110smk is a 6mph gun?
    Then there’s the idea of setting your yardage at 600 with a 90 deg wind and moving the wind speed up until you get a .6 mil adjustment. If I do that in the hornady app I’m getting an 8mph gun. So am I right doing the hornady app and getting an 8mph gun or is the bc correct and I’m getting a 6 mph gun. I’m guessing the 8mph is more like it since a 6.5 Creedmoor is a 6 mph gun I can’t really see a 6 Creedmoor being a 6mph gun as well. And if this is correct then the bc number doesn’t mean anything in this case.
    Any thoughts??
     

    Jack Master

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    @Rutter
    using the G1bc is a starting point. if you know your velocity and have a good ballistic program use the program.

    two things to note.
    1. Read lowlights comments above about turning off certain wind zones if your can. (using a kestrel for example)
    2. make sure you are using only the true wind value, no spin drift, Coriolis or alien Voodoo.
     
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    I just need a bit of help here. Sorry for being stupid or slow to understand this. You guys are saying to go off of the G1 bc. With a bc .617, With that being said my 6creedmoor with 110smk is a 6mph gun?
    Then there’s the idea of setting your yardage at 600 with a 90 deg wind and moving the wind speed up until you get a .6 mil adjustment. If I do that in the hornady app I’m getting an 8mph gun. So am I right doing the hornady app and getting an 8mph gun or is the bc correct and I’m getting a 6 mph gun. I’m guessing the 8mph is more like it since a 6.5 Creedmoor is a 6 mph gun I can’t really see a 6 Creedmoor being a 6mph gun as well. And if this is correct then the bc number doesn’t mean anything in this case.
    Any thoughts??
    For that to be an 8mph gun, you are probably pushing 3200fps.

    Adjustments have to be made for speed and altitude.

    200fps increase = 1mph increase
    4,000ft elev. increase = 1mph increase.

    The baseline numbers are 2,800fps at 2,000ft.elev....you start adjusting from these numbers.

    In all likelihood you will be using your solver to find your number. I only tell you this so you understand why you are getting a different result.
     
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    PracticalTactical

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    1 MPH at 1000 yards is a 308 only

    You are going back to old stuff where everything is based off a 308, 168 at 2550fps same thing with the USMC Wind formula, based off a specific bullet at a specific speed. You need to change the constant for your caliber and changing the constant requires you already know the wind hold.

    Wind was always voodoo because everyone used flawed data from the start. The wind rose was flawed a 1/2 value wind is not half the value but 1/2 the distance, the formulas were for a specific bullet and did not adjust for the shooter. So the old mantra was, grab a case and go out and shoot in the wind. Expensive and it requires you have the capacity to understand and learn from the misses.

    Here we give you the tools do it for your system with an actual number... it's not a guess, it's an actual adjustment.

    What I meant by 1 mph at 1000 is that the mph system you describe is about consistent for me with 1 moa at 1000 per mph... meaning 12 mph wind = 12 moa and working back from that is close to the math mph table but working backwards from 1000

    I'm not disagreeing with you I'm just working it through and relating to the way I think.

    Its actually 14 mph for my current PRS load but its close enough to make sense.

    As percentage for wind direction... I soo agree that 1:30 is not the half value... 1:00 is.

    How I think of wind angles is as though a plumb line is hanging vertically from the tip of the minute hand on a clock.

    at 1:00 the plump line is half way from center to 3
    12:30 is 1/4
    2:00 is 3/4 value

    When shooting in a head or tail wind I pay more attention to wind direction

    When shooting in a cross wind I pay more attention to wind speed.
     

    Rutter

    Sergeant of the Hide
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    Minuteman
    Nov 19, 2018
    252
    83
    For that to be an 8mph gun, you are probably pushing 3200fps.

    Adjustments have to be made for speed and altitude.

    200fps increase = 1mph increase
    4,000ft elev. increase = 1mph increase.

    The baseline numbers are 2,800fps at 2,000ft.elev....you start adjusting from these numbers.

    In all likelihood you will be using your solver to find your number. I only tell you this so you understand why you are getting a different result.
    I sent you a pm of all my results along with a few different workings. Let me know what your thoughts are.
     
    D

    Deleted member 113831

    Guest
    I sent you a pm of all my results along with a few different workings. Let me know what your thoughts are.
    I ran this in GeoBallistics, AB, Strelok Pro, Trasol, as well as 4DOF.

    Long story short, 4DOF is the outlier with this bullet. It doesn't match any of the other solvers, and all the other solvers agree.

    Your gun is a 7mph gun according to all but Hornady.
     

    MakeSawdust

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    Full Member
    Minuteman
    Feb 25, 2017
    459
    408
    Tons of discussion on this. I started using this in matches and my wind calling has improved dramatically. I don't write anything for wind on the range card. I write the range and the elevation.

    To make the math one less step at longer ranges, instead of doing the add a tenth at 800 etc, I determine that I have a 7 mph gun to 600, a 6 mph gun from 600-900 and a 5 mph gun from 900-1100 yds etc. Then, if I make a bad wind call and see the miss, I can correct the wind call in mph and run it on the rest of the stage. I can see the reticle in mph. I'm not saying you can't do this using the "add a tenth at 800+ method. I'm simply saying the mental math is easier for me personally if I do it as described above.

    Before I learned this method I would write down what I wanted to hold for wind, but when I would miss I would have a lot harder time correcting for the targets at different distances. Instead of missing the first shot and hitting everything else, I would miss the first shot and hit the second. Then I would transition to the next target and try to guess how far my range card was off with some quick, shitty math. I would miss and then correct and hit the second shot on the second target. This would more or less repeat itself throughout the target array.

    Now, I can make a wind call and shoot the first shot. If I started shooting with an 8 mph wind call, but see that I hit the edge of plate and the wind is actually 5 mph, now I can use 5 mph to do the quick math in my head for every target on the stage. Obviously, there are situations where the terrain, target angle, or gusts/lulls will dictate shooting different wind speeds throughout a stage. I find all these things much easier to manage while utilizing the bc method and doing the math in my head on every shot/target.

    For those worried about the speed/accuracy, it is very easy to look at, say .6 mils on the 600 yd target and say that is 7 mph so 4 mph is just over half of that. I visualize the reticle divided in mph instead of mils if that makes any sense. A guy can make really quick adjustments and be within .1 mils of what the Kestral would have spit out. I have actually timed out less since I started using the bc method, and I've hit a lot more targets.

    I'm pretty grateful there are people out there like Frank. Without this site and the podcast it would have taken me a lot longer to get to this point, if ever. There is a lot of good information being shared. It significantly shortens the learning curve vs. just going out and shooting and analysing and trying to reinvent the wheel.
     
    D

    Deleted member 113831

    Guest
    Tons of discussion on this. I started using this in matches and my wind calling has improved dramatically. I don't write anything for wind on the range card. I write the range and the elevation.

    To make the math one less step at longer ranges, instead of doing the add a tenth at 800 etc, I determine that I have a 7 mph gun to 600, a 6 mph gun from 600-900 and a 5 mph gun from 900-1100 yds etc. Then, if I make a bad wind call and see the miss, I can correct the wind call in mph and run it on the rest of the stage. I can see the reticle in mph. I'm not saying you can't do this using the "add a tenth at 800+ method. I'm simply saying the mental math is easier for me personally if I do it as described above.

    Before I learned this method I would write down what I wanted to hold for wind, but when I would miss I would have a lot harder time correcting for the targets at different distances. Instead of missing the first shot and hitting everything else, I would miss the first shot and hit the second. Then I would transition to the next target and try to guess how far my range card was off with some quick, shitty math. I would miss and then correct and hit the second shot on the second target. This would more or less repeat itself throughout the target array.

    Now, I can make a wind call and shoot the first shot. If I started shooting with an 8 mph wind call, but see that I hit the edge of plate and the wind is actually 5 mph, now I can use 5 mph to do the quick math in my head for every target on the stage. Obviously, there are situations where the terrain, target angle, or gusts/lulls will dictate shooting different wind speeds throughout a stage. I find all these things much easier to manage while utilizing the bc method and doing the math in my head on every shot/target.

    For those worried about the speed/accuracy, it is very easy to look at, say .6 mils on the 600 yd target and say that is 7 mph so 4 mph is just over half of that. I visualize the reticle divided in mph instead of mils if that makes any sense. A guy can make really quick adjustments and be within .1 mils of what the Kestral would have spit out. I have actually timed out less since I started using the bc method, and I've hit a lot more targets.

    I'm pretty grateful there are people out there like Frank. Without this site and the podcast it would have taken me a lot longer to get to this point, if ever. There is a lot of good information being shared. It significantly shortens the learning curve vs. just going out and shooting and analysing and trying to reinvent the wheel.
    What you are doing is perfectly viable of course, but unnecessarily complicated.

    Same goes for the guys lining things up at 600 yards instead of 1k yards when they are shooting 6mph or 7mph guns.

    If you have a 6mph or 7mph gun, lining it up at 1k yards only puts you off 0.05 mils at the closer ranges. It is an inconsequential amount of error in my opinion.

    This stuff is hard enough without making it harder.
     

    PracticalTactical

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    Minuteman
    May 13, 2019
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    What you are doing is perfectly viable of course, but unnecessarily complicated.

    Same goes for the guys lining things up at 600 yards instead of 1k yards when they are shooting 6mph or 7mph guns.

    If you have a 6mph or 7mph gun, lining it up at 1k yards only puts you off 0.05 mils at the closer ranges. It is an inconsequential amount of error in my opinion.

    This stuff is hard enough without making it harder.

    Its good to make things as simple as possible, but not simpler.

    I get the impression Sawdust gets it and has things worked out in a way that HE understands and relates to.

    Different people process information differently, but as long as they get there and in this case it works for him, who is anyone to criticize?