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The Wind Book For Rifle Shooters Book Pdf
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Delores Mertine
Dec 22, 2023, 12:10:17 AM12/22/23
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In order to interpret and apply wind compensation correctly, you have to determine the angle of the wind; how it flows across the bullet will determine the amount of drift. A tail wind or head wind will have no value; they have essentially no effect on a bullet's flight. A direct crosswind, which blows from 90 degrees into the path of the bullet, is called a "full" wind because the full effect of the wind is experienced.
The Wind Book For Rifle Shooters Book Pdf
Download File https://t.co/QhrDzP0bki
An oblique wind of 45 degrees, from right or left, has not a one-half value, but a three-quarters value. It has a 75 percent effect, even though the angle is only halfway between no effect and full effect. Most shooters initially have trouble getting this straight in their heads. The effect is not proportional because of the aerodynamics of a bullet in flight. Just remember that halfway between full and zero effect is three-quarters. Benchrest shooters use even finer values and split the wind for exact aiming. I've included this to give you a better feel for how quickly the wind has an effect once a bullet is other than at tail or head. Once it's just 15 degrees right or left, already a quarter of the wind value must be used when compensating.
To shoot accurately into a wind, compensate by holding or aiming in the direction the wind is coming from. As the bullet travels downrange, it drifts into your target. In order for this to work, however, you must know exactly how far to compensate.
The accompanying ballistic tables show wind drift for several police and military sniper loads, which you can compare to your favorite hunting loads. Although several wind speeds are listed, the most important is the 10 mph listing, I believe, because once memorized, it's easiest to compute in your head. Just about anything can be divided or multiplied when you start with a factor of 10.
Note that compensation doubles as wind speed doubles--the necessary compensation for a 20 mph wind is twice that of a 10 mph wind, and five mph is half that of 10 mph. But the differences in distances are not proportional: compensation for 600 yards is much more than twice that of 300 yards. This is because the farther the bullet goes, the more it slows down and the worse the effect becomes. In a way, this is similar to how a bullet starts to plunge at long range, when its path becomes a sharp arc.
First, determine which direction the wind is blowing in respect to a line between you and your target. For the sake of illustration, let's say it's 90 degrees and, as already seen, that would make it a "full" wind. Next, determine the speed of that wind--we'll say it's five mph. Finally, you estimate your target is 600 yards away. You're using Federal .308 BTHP Match.
If your scope lacked a windage knob, you would have looked at the target, determined that 16.1 inches is the width of a fit man at the hip, and held this far into the wind, aimed and engaged, again with perfect results.
But what about other than full-value crosswinds? Just factor in the value when determining the compensation. Let's try another example. You know the wind is 15 mph, coming on at a 45-degree oblique, and the range is 800 yards. Again you're using a Federal .308 Match ammo. The table says full compensation would be 96.1 inches, but we will only use three-quarters of that because the wind is oblique at 45 degrees. Three-quarters of 96 inches is 72 inches. So, if you have a windage knob you realize that 1 MOA equals eight inches at 800 yards; therefore, you divide 72 by eight, which equals nine, and you click off nine MOA on your scope, or 36 clicks. On another scope, you'd hold into the wind what you estimate to be 72 inches from your target--about the height of a man.
Where shooting into the wind gets tricky is when it's gusting or you must deal with several winds. Old-time shooters will tell you not to wait for pauses during a steady wind, that you'll have much better results shooting into a predictable wind than hoping a short calm lasts long enough for your bullet to reach the target.
Strong gusts require timing your shot. When faced by two winds, try to time your shot so it's fired during the slower or the least gusting or the farther wind so there's less effect and a more predictable outcome. (This is getting pretty complex, but the reason you prefer shooting through a farther wind is that there's less remaining flight time to be affected by the wind.)
For those of you having a boundless desire for more information, I've included an old U.S. Marine Corps method for computing sight changes when firing in the wind. The USMC has been using this windage adjustment method since the days of the 1903-A3 Springfield.
Click-in the two minutes of angle in the direction of the wind and aim dead-on. This is a great formula--except it's only accurate at 500 yards or less. When your target is farther, the mathematical constant must increase, as shown below:
Aside from the shooting fundamentals, wind calling is one of the most important skills you should develop for long-range shooting. Knowing how to read the wind will have a greater effect on your precision than reducing your groups through reloading. This helps any shooter who is hunting, competitive shooting or just having fun.
A wind meter is essential for learning how to estimate wind speed. Kestrel wind meters are the standard for the shooting sports. They have various models available from strictly wind readers like the model 1000 to full-featured ballistic solvers like the 5500 and 5700 models.
Next, using your wind meter again, associate wind speed to the environment. Use grass, shrubs, trees, and dust that are close to you and not far off in the distance. The wind speed and direction may be different at far distances. As you check wind speed, associate the wind pressure you feel on your body to the way the vegetation is moving. Test yourself to see if the wind meter, your body, and the environment corelate. From there, compare the vegetation and trees farther out to ones nearby. This will help train your eye on the terrain that is familiar to you. You will quickly build up a mental database that you can refer to at any time.
Once you have your wind speed, you need to figure out the wind direction in relation to the target. When you have these two, you will then be able to derive wind hold from a ballistic solver to get the bullet centered on the target.
Wind is, and will always be, an elusive shooting factor. The more you study it and shoot in windy conditions, the sharper your wind calling will be and the more precise your shots will become. Learning to do the wind calculations without tools is helpful when you need to respond quickly. Use the tools when you want the most precision.
Before we break down the wind component of the B.C. numbers, understand something equally important. We moved away from this model because we shot M.O.A. Style sights and scopes for many years. The numbers using M.O.A. change the wind value to 10 M.P.H. This speed is where the game of telephone comes into play; we just defaulted to using a 10MPH value because that matched a 308. They cut out the long hand math part and just gave you a 10MPH value assuming you had a 308 in your hand. Today with Mils, we can see the flow of the wind calls much better.
Looking at your ammo box, find the G1 number for the bullet being used. That first number is the wind speed for your rifle. Understanding right off the bat that B.C.s are muzzle velocity-dependent, if your rifle is on the fringes, as with a short barrel or extremely long one, it will not line up 100%.
We fine-tune the M.P.H. gun number by using software and setting the target range to 600 yards. I then scroll the wind speed until the pure wind value (Do not include the drifts) reads .6 Mils at 600 yards. We want the wind speed to match .1 Mils per 100 yards.
After we have determined the wind speed and applied that to our M.P.H. Gun Formulas, we have to look at the wind angle. Most people underestimate the wind because of the terminology surrounding the clock system. Most use the clock system versus degrees, but at the same time, the clock system has created a problem over the years.
First, the shooter wants to determine the direction; the lanyard is fantastic for demonstrating the wind direction. Point the Kestrel into the wind and let the lanyard help. Next, we want to read the wind for at least 1 Minute; 2 Minutes is better, but monitor the Highs, Lows, and Average speed.
I have reduced my wind zone discussion to just wind at the shooter. Yes, I recognize we have Mid Range Wind and Wind at the Target, but as a newer shooter, focus on you. The more experience you get, the further downrange your readings will be valid, but in the beginning, look at wind at the shooter.
I break the wind-down two ways: the science and the art departments. The science department is my wind meter; the art department is everything else because it is an artistic interpretation of what I am feeling, seeing, and hearing. My Kestrel matches my observations to an actual value.
If the wind is 8 M.P.H. and I am shooting at 600 yards, that means I am using .8 for my initial wind hold. Why .8, well, a 6 M.P.H. gun will move the strike .6 Mils at 600 yards, so adding 2 M.P.H. over that value, I get .8 if the wind was 12M.P.H. that puts me in my second bracket so that the wind call would be 1.2 Mils.
Lastly, I want to talk about wind brackets. As noted above, wind ebbs and flows; it does not move in a straight line. Often we see wind gusts that can be larger than the target or smaller than the target. By noting the size of the target upfront, we look at using brackets.
Wind brackets use more than one value on the plate. We have an average estimate for the wind call of .6 Mils and a gusting value of .8, so the goal would be to place both on the target simultaneously.
Other books cover wind reading in a broader discussion of ballistics or long-range shooting, such as Applied Ballistics for Long-Range Shooting by Bryan Litz. But the Miller & Cunningham book is ALL about wind reading from cover to cover, and that is its strength. The book focuses on real world skills that can help you accurately gauge wind angle, wind velocity, and wind cycles.
0aad45d008
The Wind Book For Rifle Shooters Book Pdf
Download File https://t.co/QhrDzP0bki
An oblique wind of 45 degrees, from right or left, has not a one-half value, but a three-quarters value. It has a 75 percent effect, even though the angle is only halfway between no effect and full effect. Most shooters initially have trouble getting this straight in their heads. The effect is not proportional because of the aerodynamics of a bullet in flight. Just remember that halfway between full and zero effect is three-quarters. Benchrest shooters use even finer values and split the wind for exact aiming. I've included this to give you a better feel for how quickly the wind has an effect once a bullet is other than at tail or head. Once it's just 15 degrees right or left, already a quarter of the wind value must be used when compensating.
To shoot accurately into a wind, compensate by holding or aiming in the direction the wind is coming from. As the bullet travels downrange, it drifts into your target. In order for this to work, however, you must know exactly how far to compensate.
The accompanying ballistic tables show wind drift for several police and military sniper loads, which you can compare to your favorite hunting loads. Although several wind speeds are listed, the most important is the 10 mph listing, I believe, because once memorized, it's easiest to compute in your head. Just about anything can be divided or multiplied when you start with a factor of 10.
Note that compensation doubles as wind speed doubles--the necessary compensation for a 20 mph wind is twice that of a 10 mph wind, and five mph is half that of 10 mph. But the differences in distances are not proportional: compensation for 600 yards is much more than twice that of 300 yards. This is because the farther the bullet goes, the more it slows down and the worse the effect becomes. In a way, this is similar to how a bullet starts to plunge at long range, when its path becomes a sharp arc.
First, determine which direction the wind is blowing in respect to a line between you and your target. For the sake of illustration, let's say it's 90 degrees and, as already seen, that would make it a "full" wind. Next, determine the speed of that wind--we'll say it's five mph. Finally, you estimate your target is 600 yards away. You're using Federal .308 BTHP Match.
If your scope lacked a windage knob, you would have looked at the target, determined that 16.1 inches is the width of a fit man at the hip, and held this far into the wind, aimed and engaged, again with perfect results.
But what about other than full-value crosswinds? Just factor in the value when determining the compensation. Let's try another example. You know the wind is 15 mph, coming on at a 45-degree oblique, and the range is 800 yards. Again you're using a Federal .308 Match ammo. The table says full compensation would be 96.1 inches, but we will only use three-quarters of that because the wind is oblique at 45 degrees. Three-quarters of 96 inches is 72 inches. So, if you have a windage knob you realize that 1 MOA equals eight inches at 800 yards; therefore, you divide 72 by eight, which equals nine, and you click off nine MOA on your scope, or 36 clicks. On another scope, you'd hold into the wind what you estimate to be 72 inches from your target--about the height of a man.
Where shooting into the wind gets tricky is when it's gusting or you must deal with several winds. Old-time shooters will tell you not to wait for pauses during a steady wind, that you'll have much better results shooting into a predictable wind than hoping a short calm lasts long enough for your bullet to reach the target.
Strong gusts require timing your shot. When faced by two winds, try to time your shot so it's fired during the slower or the least gusting or the farther wind so there's less effect and a more predictable outcome. (This is getting pretty complex, but the reason you prefer shooting through a farther wind is that there's less remaining flight time to be affected by the wind.)
For those of you having a boundless desire for more information, I've included an old U.S. Marine Corps method for computing sight changes when firing in the wind. The USMC has been using this windage adjustment method since the days of the 1903-A3 Springfield.
Click-in the two minutes of angle in the direction of the wind and aim dead-on. This is a great formula--except it's only accurate at 500 yards or less. When your target is farther, the mathematical constant must increase, as shown below:
Aside from the shooting fundamentals, wind calling is one of the most important skills you should develop for long-range shooting. Knowing how to read the wind will have a greater effect on your precision than reducing your groups through reloading. This helps any shooter who is hunting, competitive shooting or just having fun.
A wind meter is essential for learning how to estimate wind speed. Kestrel wind meters are the standard for the shooting sports. They have various models available from strictly wind readers like the model 1000 to full-featured ballistic solvers like the 5500 and 5700 models.
Next, using your wind meter again, associate wind speed to the environment. Use grass, shrubs, trees, and dust that are close to you and not far off in the distance. The wind speed and direction may be different at far distances. As you check wind speed, associate the wind pressure you feel on your body to the way the vegetation is moving. Test yourself to see if the wind meter, your body, and the environment corelate. From there, compare the vegetation and trees farther out to ones nearby. This will help train your eye on the terrain that is familiar to you. You will quickly build up a mental database that you can refer to at any time.
Once you have your wind speed, you need to figure out the wind direction in relation to the target. When you have these two, you will then be able to derive wind hold from a ballistic solver to get the bullet centered on the target.
Wind is, and will always be, an elusive shooting factor. The more you study it and shoot in windy conditions, the sharper your wind calling will be and the more precise your shots will become. Learning to do the wind calculations without tools is helpful when you need to respond quickly. Use the tools when you want the most precision.
Before we break down the wind component of the B.C. numbers, understand something equally important. We moved away from this model because we shot M.O.A. Style sights and scopes for many years. The numbers using M.O.A. change the wind value to 10 M.P.H. This speed is where the game of telephone comes into play; we just defaulted to using a 10MPH value because that matched a 308. They cut out the long hand math part and just gave you a 10MPH value assuming you had a 308 in your hand. Today with Mils, we can see the flow of the wind calls much better.
Looking at your ammo box, find the G1 number for the bullet being used. That first number is the wind speed for your rifle. Understanding right off the bat that B.C.s are muzzle velocity-dependent, if your rifle is on the fringes, as with a short barrel or extremely long one, it will not line up 100%.
We fine-tune the M.P.H. gun number by using software and setting the target range to 600 yards. I then scroll the wind speed until the pure wind value (Do not include the drifts) reads .6 Mils at 600 yards. We want the wind speed to match .1 Mils per 100 yards.
After we have determined the wind speed and applied that to our M.P.H. Gun Formulas, we have to look at the wind angle. Most people underestimate the wind because of the terminology surrounding the clock system. Most use the clock system versus degrees, but at the same time, the clock system has created a problem over the years.
First, the shooter wants to determine the direction; the lanyard is fantastic for demonstrating the wind direction. Point the Kestrel into the wind and let the lanyard help. Next, we want to read the wind for at least 1 Minute; 2 Minutes is better, but monitor the Highs, Lows, and Average speed.
I have reduced my wind zone discussion to just wind at the shooter. Yes, I recognize we have Mid Range Wind and Wind at the Target, but as a newer shooter, focus on you. The more experience you get, the further downrange your readings will be valid, but in the beginning, look at wind at the shooter.
I break the wind-down two ways: the science and the art departments. The science department is my wind meter; the art department is everything else because it is an artistic interpretation of what I am feeling, seeing, and hearing. My Kestrel matches my observations to an actual value.
If the wind is 8 M.P.H. and I am shooting at 600 yards, that means I am using .8 for my initial wind hold. Why .8, well, a 6 M.P.H. gun will move the strike .6 Mils at 600 yards, so adding 2 M.P.H. over that value, I get .8 if the wind was 12M.P.H. that puts me in my second bracket so that the wind call would be 1.2 Mils.
Lastly, I want to talk about wind brackets. As noted above, wind ebbs and flows; it does not move in a straight line. Often we see wind gusts that can be larger than the target or smaller than the target. By noting the size of the target upfront, we look at using brackets.
Wind brackets use more than one value on the plate. We have an average estimate for the wind call of .6 Mils and a gusting value of .8, so the goal would be to place both on the target simultaneously.
Other books cover wind reading in a broader discussion of ballistics or long-range shooting, such as Applied Ballistics for Long-Range Shooting by Bryan Litz. But the Miller & Cunningham book is ALL about wind reading from cover to cover, and that is its strength. The book focuses on real world skills that can help you accurately gauge wind angle, wind velocity, and wind cycles.
0aad45d008
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