Kentucky Windage

[CSACANNONEER]

Are there any good references that will teach you how to read wind speed?

Experience. Wind speed can vary at different lengths along a projectile path. Learning to read mirage is a great way to see what is happening at different distances from you. Or, you can be like a novice and complain about mirage instead of embracing it.

[NorCalNative]

Experience. Wind speed can vary at different lengths along a projectile path. Learning to read mirage is a great way to see what is happening at different distances from you. Or, you can be like a novice and complain about mirage instead of embracing it.

No doubt that experience is key, but are there any teaching resources that teach about mirage, dust, flags, etc?

[Duy12B]

No doubt that experience is key, but are there any teaching resources that teach about mirage, dust, flags, etc?

I was watching a 2 part video on youtube by TiborasaurusRex called "SNIPER 101 Part 31 - Wind Corrections (1/2) - Rex Reviews". He explains some common means of gauging wind speed and also explains mirage.

I also went through a few resources on Sniper's Hide's FAQ section:

• Wind Reading - More important at Gun or Target?
• Where to read the Mirage?

At your position, using a flag or dropping some grass in front of you, you take the angle of the falling flag or grass and divide by 4. That will give you your adjustment. This is a loose guide though, just to get your a ballpark figure.

I'll try all these things out this weekend (should there be wind). With all the variables, I'm hoping I'll have enough intuition to figure it out and all of a sudden get hit with an epiphany of how the rules/formulas/tips support my findings.

[as_rocketman]

So a couple more details...

Those charts are awesome help. I didn't know bullet trajectory would drop or raise depending on a head or tail wind. I will start putting up larger paper to get better readings.

There are three major wind effects on bullet trajectory. One affects "windage," and the other two affect "elevation."

The dominant effect is windage itself, i.e., it's the actual side drag on the projectile. Eventually the projectile will accelerate sideways to the point that it only sees the wind head- or tail-on, but this takes a few seconds, and unless you're shooting artillery your round will impact before then.

The other two effects move the point of impact up or down. The simplest one is headwind / tailwind. Unless the wind is straight across, it will either slightly accelerate or decelerate the bullet. This is just like speeding it up or slowing it down, and faster bullets will impact higher on the paper (if your target is past your maximum ordinate).

The last effect is Magnus Effect. This has to do with the bullet's spin. In the very instructional pictures above, you'll note the picture specifies a right-hand spin, meaning if you could see the bullet spin as you stood behind it, it would appear to turn clockwise. If instead you have a left-hand twist barrel instead of an "S" shape you will experience a symmetrical "Z" shape for different wind directions.

You can think of Magnus Effect as "rolling" the wind either under or over the bullet, and as it does so it increases the pressure below or above, which in turn moves point of impact up or down. Magnus Effect is familiar to baseball pitchers and golfers, and it's been used in paintball to dramatic effect. The physics is slightly different for us, but it's close enough.

Now, for most shooting that you're likely to do, the pattern created by varying wind directions is much flatter, and you can neglect the vertical effects of wind. This is partly because we're already adjusting our come-ups, and wind effect tends to get lumped in there. But it also becomes more pronounced at long to extreme range, and with bullets of high ballistic coefficient. In close with .22's you're not likely to see a whole lot of vertical dispersion due to wind... probably. There's no substitute for trying it and finding out for yourself.

I looked into the Appleseed Known Distance event and noticed there's one in San Jose on the 29th and 30th of this month. Unfortunately, there's a per-requisite that attendees must have already joined an Appleseed event.. and looking at the schedule there isn't a non-KD event located in San Jose on that list. Would love to join though.

We don't do normal Appleseeds at Metcalf, only KD events. Has to do with the geometry of the range and how they schedule events. The nearest normal Appleseed to San Jose is at Chabot in Castro Valley. I believe you'll find it's well worth the drive...

No doubt that experience is key, but are there any teaching resources that teach about mirage, dust, flags, etc?

There are some good books on the subject. John L. Plaster's is a good technical read. Otherwise, classes are your best bet. CMP Clinics and NRA High Power are definitely worth checking out... I'm sure others here have their favorites and can give other recommendations.

I was watching a 2 part video on youtube by TiborasaurusRex called "SNIPER 101 Part 31 - Wind Corrections (1/2) - Rex Reviews". He explains some common means of gauging wind speed and also explains mirage.

Yup, the "Sniper 101" series is worth watching.

The method I find most useful for wind estimation is to read wind signs. For example, the OP mentioned blowing dust, which rarely occurs below 13 MPH, but not clouds of dust which mean 19+ MPH. This is only accurate to +/- 3 MPH or so, not nearly good enough for precision shooting, but usually good enough for field shooting which is my game. And just that one little detail (plus wind direction) was enough for me to estimate his holdoff to within a couple of MOA.

For precision shooting -- any shooting really, but a must for precision shooting -- you should take maximum advantage of target feedback. If there's someone pulling targets and marking hits for you, you can learn what the wind is doing to your shots with a quickness (provided you're making your calls). This is bar none the best way to learn.

Other tools, getting a spotting scope and reading mirage is a great tool, provided you brought your scope. Go ahead and put up flags, both to see how consistent the wind is and also how much it blows. But don't be sloppy with your flags. Make them a consistent length and a known distance off the ground, and they'll blow the same way when they feel the same wind.

Think about what professionals do -- pilots. They use a "wind sock" to show them both direction and wind speed next to the runway. A well constructed flag will be equally consistent.

And as others have said, it's going to take experience. The more the better.