Do windflags lie?

B

B. Harvey

Guest
This is a question I have seen a couple of times and several have answered that they do lie, but then put a smiley behind the sentence or whatever.

If we look at what a windflag is, and how it is made, then it is easy to believe that they lie, and often.

Props, all of them I would guess, have a certain amount of slip, cavitation or whatever else you would call it. But they would have a certain speed where they are most efficient, and give the truest reading. My props are a 10" pitch and if you do the math, after maybe 1.8 mph (and giving them time to fully ramp up to that speed) are at 3 revolutions per second. After about 5 mph they might as well be solid discs.

If you have 4 flags, then trying to keep track of rps would be unrealistic.

Enter the tails. Some are very light and some are heavy. The light ones, after maybe 3-4 mph have given you about all it can. The heavy ones aren't worth dirt before maybe 3 mph and might be good to 7-10 mph, or until they are past a certain angle.

If you look at survey tape, it just flutters about at any speed. I have never been able to get along with this stuff. Sail tails (light or heavy) are much better but also have a working range.

Tails, as they rise, loose the initial surface area they had and the more they rise the less they have. This makes me wonder if a tail at say 45 degrees takes less or more wind to push it up even more. What I mean is, say it takes 4 mph to get it to 45 degrees, does it then take another 4 mph to get it to 90 degrees? Since it looses surface area it would seem to take more wind. But since it is getting pretty flat, does it get the float effect and actually take less wind to push it higher? Also, if a tail is out flat at 7-8 mph, and the wind is actually 12 mph, you already have a 4 mph error built in.

The vane just does what it can to tell direction and it seems to do a pretty fair job at that. It does seem to do a better job than a prop or tail.

My flags are a combination of a Wayne Smith flag, with two tails, one a snuffy light, the other a 2' piece of VHS tape, and a 2 blade 15" prop on a slow flyer gearbox. They are balanced very well.

The props start turning at below .5 mph. The VHS tape starts fluttering just before the props start. The sail tail starts at around 1 mph. The vane will turn in a little less than a 1 mph wind. This flag is sensitive.

Now, at the PSL match, the wind at times had my tails parallel with the ground, the props looked like solid disc's. Don't know how fast the wind was blowing, but I was holding quite a bit. It was during these times, as well as a few others, that my flags were lying, or they were totally missing something that was making me miss.

The Kettlefoot PSL match brought forth a desire to have an indicator that would respond quicker, and give a better indication of speed, as well as visually help show which conditions were more stable.

After testing for the past week, I have found something that has verified that my flags are not as good as I thought they were. My flags actually miss a ton of activity that is happening. They either respond anywhere from 1-2 seconds behind the test piece, or they flat miss the condition change all together.

The funny thing is that, with going to matches and seeing other flag, prop, tail designs, and anything else I could look at, it made me think I had the best flags that could be had.
A friend of mine brought up a very good point though. He asked, "If all the other guys shooting had crap windflags, how could they beat you"?

This made me ponder a few other thoughts. One mans treasure is another mans junk, and if I thought all the other flags were sub par, how then do these guys shoot so well? How do they read the flags so well when the flags have built in limitations or errors?

I know what you are thinking, "I don't shoot when my props are turning that fast, or if my tails are flat"

If this is true you'd score a ZERO if you went to a match where the wind was a constant 10-20 mph. Not to mention any windflag I've seen would be useless except for direction.

These things at least confirm in my mind that the top shooters already know the limitations of there equipment, and how to work within those limitations to achieve what they do.

But yes, flags do lie.
 
That's a pretty bold statement..:eek:..I have tried to get a polygraph on my windflags, but they will not answer any of the questions...:D..all they do is smile..:)
All kidding aside the skill of reading windflags and range conditions is eqivalent to a PHd in ??meterology??..there is a lot more than wind angle and velocity which most of the time comes like swirling currents of water...because the wind is bouncing off of every stable object it comes in contact with...it will waver and wobble across the range making the wind flag vane dance from side to side...and ad to that the relative humidty (water in the air) and how it distorts the image...to begin..one must find the ammo/load that is most accurate in his rifle...and that in itself is a chore considering you have to deal with conditions of some sort at all times...
Then once the rifle and load are as good as you can get them...go to a sighter bull and find out which flag/tail or probe position gives you...shoot heads up and watch the flags...if nothing is working change your method and chose a single flag or a combination of flags to test on the sighter...
I once shot my best group at 200 yards using my 25 yard flag and my wind probe (also at 25 yards) and nothing else...it was something I found by trial and error while shooting on the sighter and just trying different combinations of flags and probe...
I have lost matches because I chose a wrong combination and convinced myself to shoot it even though I only got 3 of my 5 shots to print in the same spot...my mistake NOT a lying flag..:rolleyes:
 
Yes

My flags lied to me, so I shot them. Now all they do is lie there on the ground with their eyes wide open not saying a thing. I'll stick with the Wind Probe for now.
Sorry about that.
 
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I agree with Beau, they don't lie. We just don't always understand what they are trying to tell us.
Fred K
 
I would agree we do not understand what they are telling us. Also, they are telling us what happened .5 sec or 1 second ago. I like to shoot straight over the top of my flags, so I realize they are slightly behind. I try to also watch the flags on the bench next to mine so that I can see any major changes that are coming, otherwise I get one of those shots that goes off target and then my flags change to confirm where the shot went. The flags were slightly behind. I thought it was interesting that DJ Hepler said in the PSL interview that he likes to put 2 rows of flags to his target.One row on each side of the target.(I have also seen Marion Collier do this). I think DJ & Marion are correct in doing this. I just do not like to carry around that many flags.
To determine velocity, I use extremely light tails that blow first, then the props start to turn, and then my probe will move. I have no idea what the actual wind speed is. I do not really care. When I pull the trigger, I try to take a snaphshot picture of the flags and probes in my mind. Then I know my bullet goes to point A when the flags look like this picture. I do not know the velocity of the wind, I just know where the bullet is likely to hit when the flags and probes are in this particular position.
 
The tests I have been running have shown the flag to be behind the probe (my own design) by a good second. This is even on a 180 switch which would have the tails getting the switch first. But the probe still picks it up ahead of the the tail. In a calm condition, where tails prop and all are motionless, then hit by a sudden gust, from any direction, the flag looks confused where the probe just shows what is happening, unless it is a head or tail wind of course. The flag itself just sort of flounders around. But, if it is a sudden hard gust from calm, and from a single direction, then the flag gets with the program pretty quick, but still well behind the probe. The two rows of flags is something I have thought of, but like most shooters, prefer not to lug all that around. Might be one reason DJ has won so much, being a smart shooter.

There have been many times I would have my eye on the flags, fire, and just after firing, the flags change, and yes the shot went out.

If using two rows of flags with a set 3 feet either side of your bullet path, and the wind is blowing 5 mph (7.33 feet per second), and your flags are .5 to 1 second behind the change, you see what is going to happen. At best the .5 second delay means the change has already affected your bullet path.

At the moment of firing a bullet, any and all data is used to aim that bullet, and a delay of info even half a second can make all the difference.
 
When Bill Calfee built my rifle we tested it and Bill didn't use any wind flags. He said that Selby Wright had taught him to use what nature provides, instead of man made wind flags. He said Selby taught him that nature provides the absolute best wind indicators and that Selby taught him that nature's wind flags "don't lie"! I remember Selby shooting and he was always watching the subtle changes around him, leaves, cigarette smoke, things like that.

Bill does not use man made wind flags when he tests his rifles. He says he uses what nature provides, as he must test the value of his metal, not his ability to read man-made wind flags, which according to him, do lie. If you've ever shot a test session with him, it's kind of amazing. He's telling you what the wind is getting ready to do by watching the grass and the leaves and whatever else. There are no flags. I remember reading a book about benchrest where the author described basically the same thing but he did use flags. Lots of times you will get caught by a switch if you're not watching pretty far in every direction. The flag has to overcome inertia before it moves, and often you can see the tail move long before the flag turns. You must be as one with the flag and you must be as one with nature.
 
Brian,
What wind velocity does it take to change the bullets path? Will the .5mph wind deflect the bullet? or does it take more than that?
 
The deflection depends on the twist of the bore and if the wind is the same (flag point/wind velocity) along the entire 50yds. At least that is what I find.
I also find flags on both sides is the best. My homemade probe always shows movement before pointers, but not always before the tails.
Fred K
 
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Brian,
What wind velocity does it take to change the bullets path? Will the .5mph wind deflect the bullet? or does it take more than that?

Dan,

I use Professor Art Pejsa’s software for my research and testing with projectiles in the transonic range of velocities and to the best of my knowledge it’s the most accurate available for this purpose.

Using a ballistic coefficient in the .15 to .16 range which is close to what McCoy observed at the Ballistic Research Laboratory with Eley and RWS round nose bullets shows a wind deflection of 0.04” at 50 yds for a .5mph wind.

Landy
 
Landy,
Would the flat nose Eley bullet have a better ballistic coefficient? Does the bullet deflection increase proportionally with wind velocity increase? Also, are you sure you are a corn farmer? You seem awful smart.:D

Fred K,
I would agree with you. It also seems that some lots of ammo will buck the wind better than others. I am not sure how that is possible, but it has been my experience. I do not know if it is a velocity difference or what.
 
Dan,I think that you asked me about my Paddle flags at the PSL shoot at Bristol,These are the only flags that give a absolute reading in both angle & velocity.& the instant let can be seen ,as the paddle set up imediately,no lag time.The paddle can be calibrated as where all paddles are at the same exact setting for velocityThey work better in stronger winds,But are sensitive in light blows,but need more attention,because of what i call suck back conditions,These are the only flags that will show this condition,It is a narrow window that does come & go in a instant,But it is a stable condition & can be shot if you know when to shoot it. BILL
 
If a red mongolian butterfly in Jakarta flaps his wings does that result in an 8 ringer on bench 7 at Kettlefoot?
 
Ok, new shooter chiming in here. Is it a myth that a puff of wind in the first 10 yards will move the point of impact more than a puff in the last ten yards?
 
I wouldn't think that would be a myth would it. Look at it this way. Let's say you're walking straight towards the target and at ten yards there is a huge pile of bear crap in the way, so you sidestep it at an angle but you don't correct your path afterward. Assume the same thing only the bear crap is 10 yards away from the target and you sidestep at an angle with again no correction in your deviation. Which way would you be further away from the target at 50 yards? Of course with a puff of air you have to assume all other things are equal.

Seems fairly logical, but it doesn't always seem to work that way, but the laws of physics always apply.
 
Dan, I do not know if a .5 mph wind will move the bullet, but I would think it would. Measuring the conditions and velocity at 10 and 50 yards, the BC of EPS calculated out to .145 . According to JBM, a 10 mph wind will give 1" of deflection at 50 yards. So, a .5 mph wind should give .050" of deflection, or a half ring hold on the RBA target.
 
Salor
It seems the wind has more effect when the bullet is slowing down the most. Therefore the wind will effect the bullet more in the first 10yds because that is when the bullet is slowing down the most.
Fred K
 
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