The Los Angeles Handgun - Rifle - Air Pistol Silhouette Club

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There's NO Such Thing As The Wind
By Todd Spotti
 
     I shoot at a public range where I get to see a wide variety of people practicing many, many different shooting disciplines. Black powder, military surplus, varmint, high power hunting rifles - you name it and itís  there. Among the most interesting are the 22 rimfire benchrest shooters. They shoot bench rest rifles that are just as technically advanced (and expensive) as the big bore bench resters. If anyone knows something about shooting in the wind, itís these guys. Let me explain.
 

"The dual vane Hood wind flags are more sensitive than standard flags."

     Instead of shooting groups at 100 yards, they shoot at a 50 yard American Rimfire Association (ARA) target that has 25 bulls printed on it in 5 rows of five each. The center of each bull is only a half inch in diameter and 100 points is awarded per center punch. Fewer points are scored the further away from the center that the bullet hits. A perfect score is 2500 points.
 
     ďSo whatís the big dealĒ you might say. Theyíve got that big, three thousand dollar 10.5 lb gun sitting on a fancy rest, leather or cordura bags filled with exotic zircon sand, a state of the art Leupold 45X Competition Series scope sitting on the top, a click adjustable barrel tuner, and hand selected lots of the very best Lapua and Eley ammunition. How could you possibly miss? Well folks, a perfect 2500 score has been only shot ONCE in the history of ARA competition. Even a target with a score of 2400 is so rare, it has to be sent to their headquarters to be confirmed. So why aren't perfect scores shot more often? Wind.
 
     If there was such a thing as a 50 yard vacuum chamber where a space suited rimfire benchrester could shoot his rifle, all the bullets would very likely go into the exact same hole with boring regularity. However we live in the real world where the air is always moving - even when it seems like it isnít. Another fact of life in this real world that we live in is that when fired, a 22 bullet is very slow. Itís also very light in weight. Consequently, both of these characteristics make it very susceptible to every little bit of air movement that it encounters on the way to our target.
 
     Let me give you just a few examples of wind situations that Iíve personally observed while watching bench-resterís wind flags.
1.  The wind is blowing straight out from the firing line and the propellers on the flags at 5 and 50 yards were spinning rapidly while the propeller on the one at 25 yards was motionless.  How is this possible?
2.  All three flags pointing in radically different directions (very common).
3.  Two flags side by side but set at different heights are pointing in totally different directions.
4.  Three flags set in a row 10í long, all at the same distance, and all pointing in a different direction and all indicating different wind speeds.
5.  A flag at 25 yards rotating continuously in a 360 degree circle.
     I could go on for some time with lots of other examples, but the point Iím trying to make is ďThereís no such thing as THE wind.Ē There are many, many winds between us and the target, and theyíre all doing something different. Itís kind of like what happens when you stir your coffee. First you move your spoon clockwise, then counter-clockwise, then back and forth. Whatís happening in your cup is similar to what happens at the range between you and your targets. There are eddies, swirls, changing currents, cross currents, whirlpools, surges and who knows what else. Itís also my personal and unproven belief that there may also actually be moving bubbles of lower or higher barometric pressure caused by small temperature variations that can cause shots to unexplainably go high or low.
 
     Anyone who has shot silhouettes for any length of time knows that air movement affects our bullets whether itís the little 22ís or even the big bores. Well, you might say ďIíll shoot heavy bullets. Surely they wonít be pushed around as much.Ē Oh boy, I canít tell you the number of times when Iíve shot a 44 Mag revolver with 240 grain bullets in high cross winds where I had to actually aim at the empty space between the 200 meter targets in order to get a hit on the adjacent ram . ďIf big and heavy wonít do it, Iíll go for a really fast bullet. The wind wonít have enough time to work on it.Ē That doesnít work either. I used to shoot a XP 223 for half scale. My velocities were typically around 2700 fps and I got lots of 40ís - except when the wind was blowing. Then you could just forget it. 
 
     So what can we do about air movement? Actually the only thing we can do is to try to understand it. I say ďtryĒ because itís just totally impossible to understand it completely. Thereís just too much going on at the same time. I know people who have been shooting big bore benchrest for over 30 years and have been trying to ďdopeĒ the wind all that time. They freely admit they know almost nothing on the subject - and not for the lack of trying or the amount of money theyíve thrown at the attempt.
 
     That brings us to the subject of wind flags. A wind flag is a weather vane type device that indicates the direction of air movement. They come in two general configurations i.e. either single vane or double vane. I like the doubles mainly because I think they look cool and I believe theyíre more sensitive. Both types do a good job however, and theyíre about the same in price.
 
     Additionally, flags are often equipped with a multi-bladed propeller on the front and/or a broad ribbon type tail on the rear. The purpose of the propeller and/or tail is to give an indication of air velocity by noting either how fast the propeller is rotating or how far out the tail is being blown. Most rimfire and center fire benchresters will have at least three flags set out in a line out to their targets. Many will use more.
 
     Let me say right up front, that using wind flags during a handgun silhouette match isnít very practical if you use the Creedmoor position. If you could, youíd want a flag next to each target youíre shooting. You say ďHey, thatís crazy. You donít need to do that!Ē  Well ideally, you do. Many, many  times Iíve seen wind flags standing only a few feet apart across in a line actually pointing in totally different directions, and where oneís propeller is spinning rapidly and the otherís isnít moving at all. Even though having a flag for each target would be ideal, itís totally impractical.
 
     Another problem occurs when your knees are drawn up in front of you while in Creedmoor. Theyíre likely to block your view of any flags that do happen to be out there. If not then, they probably will when you move to the next bank. Most importantly, itís also very difficult to focus and concentrate on your sights and to watch the flags simultaneously.
 
     So what CAN you do with flags? For one, you can use them when developing loads to help determine the optimum theoretical accuracy of a given combination of components. Second, and perhaps most important, you can use them try to learn the general air movement conditions on your range and determine how they affect bullet placement. This is particularly important when shooting big bore revolver and 22 rimfire as both are particularly affected by the wind.
 
     Letís first take a closer look at wind flags. As mentioned before, flags come in all kinds of styles and colors. I like the flags made by Hood Custom products (www.benchrest.com/hoodpress/wind_flags/html). Theyíre double vane, meaning there are two vanes set parallel to each other with a single lead counter weight out front. The purpose of the counter weight is to balance the front and rear portions of the flag to insure it will turn smoothly on its pivot point with minimal drag. The vanes on wind flags are often made of a plastic honeycomb material making them light, strong, and waterproof. However, Iíve also seen flags made of heavy cardboard and even sheet aluminum. On the Hood flags, the outside of one vane is colored a very bright orange and the outside of the other vane is colored a very bright lime green. The inside of both vanes feature broad vertical black and white stripes. The orange and green colors make it easy to see what direction the vane is pointing, while the stripes can help you quantify the direction i.e. ďone stripe into the orange, two stripes into the green, etc.Ē
 
     As mentioned before, flags can give an indication of wind velocity by observing a propeller on the front or a tail on the rear. Most people have both on their flags. These devices are useful, however they have limitations in that once the velocity of the wind reaches a point, the propellers and tails get maxed out. In other words, if the propeller is spinning as fast as its design will allow at 10 mph, if the wind picks up to 11 mph, the propeller canít spin any faster. Even if it could, you still wouldnít be able to tell any difference - a blur is still a blur.
 
     The same is true of the tail. If itís standing straight out at 10 mph, itíll look exactly the same at 11 mph. However, with tails, you do have a little more flexibility in that there is a wide variety of materials that are used that react differently in the wind. Some tails are made of a strong but light plastic which works very well in light winds but get maxed out very quickly in higher wind conditions. Other tails, like on the Hood flags, are made of a heavier nylon material that isnít as good in light winds but works well in moderate to heavier winds. Someone whoís serious about discovering the effects of the wind would probably be well advised to have two sets of tails (light & heavy) that you could take on and off your flags to cover all the bases.
 
     Obtaining your flags is only half of the equation. Now we need something to put them on. We have two choices. One, there are the classic 3 legged music stands. Theyíre light weight, stable, and generally very versatile in that they can be used on every type of moderately level ground there is. However, they can blow over if the wind gets up to the 20-25 mph range unless you put a sandbag on one of the legs. My personal feeling is if the wind is THAT high, itís time to go to the club house to get a cup of coffee. The other choice to mount a flag is a steel stake with a foot rest that you use to push the stake into the ground. I understand that theyíre popular in the East. Out here in the rocky West, the music stand is a better choice. Interestingly, both types of stands cost just about the same.
 
     When you buy your flags, if at all possible, also buy your stands from the same maker to insure that theyíre compatible with each other. Hereís the deal. All music stands have to be modified by the seller to install a 2-4 inch steel pivot pin on their tops. A female pivot joint on the flag slips over the standís pin and thatís what the flag swivels around on. Turns out that pins come in two diameters i.e. 1/4Ē and 3/16Ē depending on the standís seller. So if your standís pin is one diameter and your flag accepts only another, youíve got a problem. Hood doesnít sell stands, so I bought mine at Sinclair International. Hood will make their flags to accept either size pin, but first you need to know what size is on your stands. Also make sure that who ever you buy your stands from furnishes them with the pins installed. Interestingly, some donít. Donít ask me why not.
 
     After I got my stands and flags, I went a couple of steps farther to make them more wind sensitive. This is necessary because there is always a lag between any change in air movement and the flagís reaction to that change. We want to minimize that lag time and make that flag as reactive as much as possible. The first thing I did was to grind a point onto the top of my standís pivot pins with my little bench grinder. (Originally, the steel pivot pin had a flat top.) I figured the flag would turn easier in light air if the pin were pointed, and so it did. I also replaced the optional Hood daisy wheel propeller. The wheel is large and meaty and probably is very good in really breezy conditions, but its relatively heavy mass isnít very sensitive in light winds. My good friend Bill Racer took a much lighter propeller from an inexpensive K-Mart lawn ornament and fitted it with a little piece of aluminum tubing in the center of the hub so it would fit on the shaft of the Hood flag. A piece of brass tubing would have been better (less friction), but none was available at the time. Both these simple modifications definitely increased the flagís sensitivity. To put the icing on the cake, I then lubed both the pivot pin and the propeller shaft with a graphite solution. Both ďLock EaseĒ or ďDri SlideĒ work well for this purpose. The flags are now much more reactive than before. Modifying flags is pretty common and some bench-rester's even will go as far as to use miniature ball bearings on their propeller shafts.
 
   One thing about flags though is the fact that they can only give you an indication of what the air is doing at the precise location where the flag is sited. In other words, it wonít necessarily tell you how the air is moving just 5 feet away. This is a major, major limitation. However, there is a simple, very low cost device that can. I canít take credit for this idea and unfortunately I donít know who to give the credit to. Itís just one of those things that travel around the grapevine where many ideas are traded but often are never actually tried. Well, I decided to try it, and found that it works big time.
 
     Itís simply a string attached to something on the shooting bench ( I use a sandbag.) and which is stretched out to fifty yards. Youíll probably need a stake or something similar at 25 yards to prop up the sag in the line at that point. Tie the far end to a small hook or eye in your target stand or to another stake. Now take a strip of plastic surveyorís tape about 18-24Ē long and tie it to the string at 5 foot intervals. Surveyorís tape in various colors can be purchased at Home Depot for around $3.50 or so. The tape is very thin, very light, and extremely reactive to the slightest air movement. For lack of a better term, I call this device a ďwind lineĒ. Believe me, with a wind line out in front of you, youíll be able to see everything thatís happening and I guarantee that youíll be amazed at its complexity. However, be prepared for jokes and jibes from your friends and fellow shooters when they first see the wind line. Theyíll soon change their tune however when they see the groups you can shoot using it .
 
     The wind line is particularly useful in those situations when you know something is happening out there that the wind flags arenít telling you i.e. the bullets arenít hitting where the flags say theyíre supposed to be hitting. Let me give a quick example: your three flags are motionless indicating there is no air moving between you and your target. You fire a couple of rounds and your shots are off - way off. What happened? Obviously, there was moving air out there that wasnít being detected by the flags. ďHow can that be?Ē you might ask. Well with a wind line, Iíve observed narrow bands of wind actually moving between the flags. Obviously, if you donít know itís there, you canít compensate for it. As I like to say, a wind line actually tells the whole story about air movement between you and the target.
 
     The wind line does have a minor disadvantage though. It can be awkward to wind up at the end of a shooting session. I kind of loop mine up like an extension cord and then tie things together with a garbage bag twist tie. Conversely, the wind line is also awkward to unwind as youíre deploying it out to 50 yards. If youíre not careful, things can get tangled, so take it slow. I probably should look into coming up with some kind of reel to wrap the wind line around. Another small disadvantage of a wind line is that under some circumstances, all those fluttering tails can appear to overlap each other and kind of blur and blend into each other. Just take a moment or two to look things over, and youíll figure out whatís happening. I also use my wind flags simultaneously with my wind line so if Iím not sure what the wind line is doing, Iíll look at the flags for a supplemental clue.

     So how do you use these various devices? First of all, let me say this is all art and no science, but there are two basic methods. One is passive and one is active. The passive method uses the wind indicators to identify a ďconditionĒ. A condition is a set of circumstances indicating that the air is in a certain state of being. For instance, in an idealized situation, this might be when your three flags  are pointing all in the same direction at the same time and the propellers are all rotating at the same speed. When this occurs, you fire your first shot no matter which direction the flags are pointing or how fast or slow the air might be moving - just as long as all three are doing exactly the same thing simultaneously. After the shot has been fired, the condition will probably change and the flags will probably be swinging around in different directions. So now you wait until the original chosen condition repeats itself. Then you fire your second shot. Since the second shot was fired under the same set of circumstances as your first shot, it should be right on top of the first bullet hole - all other things being equal. Of course they never are exactly. But, if your second shot is off, you know itís likely because of the load or shooter error - not the condition. If youíre really lucky, a condition may hold long enough for you to fire all your shots. The chances are though, that youíll have to just be patient and wait for your condition to repeat itself. The most desirable condition is of course using the flags or wind line to indicate that there is no wind present at the moment. When that precious time occurs, get your shots off as soon as practical to take advantage of the situation. The passive method is used primarily for shooting groups when you donít care where the group is located on the target board. Your only concern is the size of the group, not itís location. If you do care, then the passive method would then be used only to indicate when the wind had stopped moving.

     The active method utilizes a wind line or wind flags to observe their positions and then based on that information, the shooter compensates for the air movement by changing their aim point. This is very difficult to do and takes a lot of experience, skill, intuition, and luck. This method is used when weíre trying to place our shots in a specific place like the center of a 22 shoot off target or the center of a bull. Let me give an simple example. Say all your three flags indicate that the air is moving from right to left at a moderate speed. Based on your previous experience, you estimate that your shot will be blown an inch to the left. Consequently, you hold an inch to the right to compensate. If you were shooting an ARA benchrest target, you could put a shot on one of the sighter bulls to get a better idea of how far over the wind would take your bullet. Of course thatís not an option when shooting silhouettes. However, with a lot of experience, it is possible to become very skilled at estimating wind drift.
 
     One last point on the passive/active methods of using wind indicators, itís not a case of using one or the other. Almost all 22 benchresters use both methods during competitions. In situations when the conditions are constantly changing second to second during a match, you just canít wait forever for your favorite condition to return. Youíve got a time limit to contend with, so you go active. On the other hand, if the movement of the air stops for a period, you go passive. The moral of the story here is that you have to be flexible in how you use either a wind line or flag.

     So there is it. Trying to figure out what air movement is happening at any given moment is extremely difficult and you need good tools to do it. Then, trying to come up with a way of dealing with it is even tougher, and the only tool available for that job is that bowl of Jell-O between our ears. However, if we want to hit small targets and shoot small groups, weíve got to become serious students of good old Mother Nature. Two things about Mother Nature always have to be remembered though. One - sheís the one in charge, not you. Two - sheís got a wild sense of humor.

Good luck and good shooting, Todd

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Warning: All technical data mentioned, especially handloading, reflect the limited experience of individuals using specific tools, products, equipment and components under specific conditions and circumstances not necessarily reported in the article or on this web site and over which IHMSA, The Los Angeles Silhouette Club (LASC), this web site or the author has no control. The above has no control over the condition of your firearms or your methods, components, tools, techniques or circumstances and disclaims all and any responsibility for any person using any data mentioned. Always consult recognized reloading manuals.