By Damon Cali
Posted on February 21, 2012 at 02:25 PM
Wind reading is one of the more challenging skills for a long range precision shooter to master. Spend a little time playing with a ballisics calculator, and you'll know what I mean. At 600 or 1000 yards, a 10 mph gust of wind will push your bullet feet off of your point of aim. In competition, that means lost points.
Reading the wind has shooters resorting to all sorts of shenanigans to help. Benchrest shooters litter the range with cartoonish wind flags draping with windmills, ribbons and other paraphernalia. High power shooters have to rely on huge range flags, often placed in the worst places. But the goal is always to try to figure out how fast the wind is moving and in what direction.
At a high power clinic hosted by the Marine Corps Rifle Team at Quantico, I once learned a few tricks to help keep track of the wind speed. The simplest was to take a couple of small blades of gras and drop them. Eyeballing the angle of their fall would tell you the approximate wind speed. So the story goes, at least. The engineer in me wanted a "better" way.
So I picked up a Speedtech SM-18 SkyMate Hand-Held Wind Meter. (Update: a newer version of the SkyMate is available from Brownells. It's a simple device consisting of a replaceable propeller, an LCD screen, a thermocouple, and a couple of buttons. To see how fast the wind is blowing, you just hold it up and let the wind spin the propeller. The wind speed is then displayed on the LCD screen, which updates every second or so. As a side benefit, the thermocouple will tell you the air temperature. There are several combinations of wind speed and temperature units, including the shooter friendly miles-per-hour and fahrenheit. The last relevant bit of information is that there is a threaded hole in the unit meant to fit a standard camera tripod, which can come in handy at the range.
So how does it work? Pretty well. I don't know exactly how accurate it is, but it is surely better than my eyeballs. It couldn't be any easier to use.
The downside is that the LCD screen is on the wrong side for shooters. We're usually interested in the sideways (left to right) wind, and in order to measure that wind, the unit must be turned so that the propeller (and LCD screen) are facing the wind. Not much help when you're on the firing line if you can't see the screen.
But the value of the Skymate wind meter is not so much in using it to guide your aim on the line, but to help calibrate your eyes. On the firing line, a wind meter is a bit of a distraction. But if you can remember what a 5mph breeze feels like because you measured it a few minutes prior, you'll have gained some confidence in your instinctive wind reading ability. I like to spend a couple minutes observing the range with the Skymate in hand to help me get a feel for what the wind is doing and how hard it is blowing. I find that a quick "brain calibration" to be quite helpful.
So is it worth it? I'd say so. There are more expensive, more feature-laden versions on the market as well, but they all do pretty much the same thing, so why spend more?
Damon Cali is the creator of the Bison Ballistics website and a high power rifle shooter currently living in Nebraska.
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