World Record Shot
On the 22nd of June 2017 a sniper team operating in the Middle East had made a successful kill at a distance of more than two miles. The team, deployed to fight the Islamic State, killed an ISIS fighter at a distance of 3,871 yards. The shot was a record breaker and more than a thousand yards farther than the previous world record. The shot, which bordered on the impossible, was made only slightly less so by the skill of the snipers involved.
Reports that two snipers assigned of the Joint Task Force 2, Canada’s elite Special Forces unit, had shot an Islamic State fighter in Iraq at a distance of 3,540 meters, or 3,871 yards. The sniper team was stationed on top of a high rise building; the shot took almost ten seconds to reach its target. The sniper and his spotter used a McMillan TAC-50 .50 heavy calibre sniper rifle.
To understand the complexity of the shot, it’s best to start with a sniper maxim:
Sniping is weaponized math.
Although a .50 calibre sniper rifle bullet can fly as far as five miles, a host of factors including gravity, wind speed and direction, altitude, barometric pressure, humidity and even the (Coriolis Effect) is most apparent in the path of an object moving longitudinally. On the Earth an object that moves along a north-south path, or longitudinal line, will undergo apparent deflection to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This acts upon the bullet as it travels.
Even worse, these effects increase the distance the bullet travels.
A successful sniper team operating at extreme distances must do its best to predict exactly how these factors will affect the bullet and calculate how to get the bullet back onto target.
The first and most influential factor on a bullet is gravity. A bullet begins to lose energy as soon as it leaves the muzzle of a gun, and as it loses energy it loses the ability to counteract gravity.
The farther and slower a bullet flies, the more Earth’s gravity will pull the bullet downward. This is known as “bullet drop,” and even the most powerful bullet, such as the .50 calibre round used by the TAC-50, will invariably experience it.
In most shooting situations, bullet drop is only a matter of a few inches or more.
The Canadian snipers, on the other hand, had to deal with a phenomenal amount of bullet drop at 3,450 meters, the bullet would be expected to drop 6,705 inches!
Ryan Cleckner, a former U.S. Army Ranger sniper and author shows the ballistic data for the shot here
As the bullet is traveling subsonic at a spend of 940 feet per second, the bullet is diving an average of nearly two inches per foot of forward travel, with the problem getting much worse as distance increases.
In order to make the shot the Canadian snipers had to counteract the staggering amount of drop. Being on a high rise building or hilltop was a must. The rest of the drop correction had to be done within the rifle’s scope, which can be adjusted for drop, and a scope mount that was angled upward for extreme long distance shooting.
Ryan Cleckner’s data also provides other useful information. Bullet flight time, from the muzzle of the Canadian sniper’s gun to target was just over seven seconds.
The bullet was traveling at 940 feet per second when it hit Islamic State fighter which means it slowed to below the speed of sound.
Finally, after traveling more than two miles the bullet hit with 1,472 foot pounds of energy, greater than most M16 bullets at point blank range.
Another major factor that would have affected the shot was windage.
When shooting at extreme distances, even a mild wind of five miles an hour will have an effect on the flight of a bullet, slowly but surely nudging it off its flight path toward the direction of the wind. At 400 yards, a .50 calibre bullet will be nudged 2.5 inches off its path by a five mile an hour wind.
At 3,800 yards that increases to an incredible 366 inches. In other words, the snipers had to assume their bullet would impact just over thirty feet in the direction of wind travel and plan accordingly.
Other environmental factors played a hand in the shot. Air pressure (generally a function of altitude), temperature, and humidity are factors most shooters at ranges of 500 yards or less rarely encounter, become major issues at 3,800 meters. These factors are mitigated by the use of wind sensors, barometric pressure readers, and knowledge of local weather conditions.
To complicate matters, these conditions may change so that a shot taken on a cold morning will be much different in the heat of the afternoon and snipers must recalculate the shot accordingly.
Earth itself, and the position of the shooter and target on the globe become factors at long range.
Coriolis Effect It dictates that bullets shot in the northern hemisphere drift to the right, while those shot in the southern hemisphere drift to the left, and this phenomenon increases the farther one gets to the poles. Furthermore, shooting east with the rotation of the earth will cause bullets to strike high, while shooting west will cause the same bullet to strike low.
Even the construction of the rifle itself affects the shot.
A high quality barrel will naturally be more accurate and the rifle involved in the shot,
The McMillan TAC-50 is one of the best around.
The barrel rifling has a spiral-like pattern that makes the bullet spin in flight, stabilizing its, imparts “spin drift.”
According to Ryan Cleckner, a rifle with a right-hand spiral twist will send a bullet up to ten inches to the right at 1,000 yards.
How much spin drift would affect the shot at 3,800 yards was essential information for the Canadian snipers.
In taking their record-breaking shot, the Canadian sniper team had to consider all of these factors misjudging one would have caused a clean miss and it is an incredible testament to their skill that they were successful.
The average man-sized target is just twenty four inches wide, leaving zero room for error in a two mile shot.
The shot took place at the extreme edge of viability, given the current levels of sniper technology.
While the JTF-2 shot will almost certainly be equalled, it seems unlikely it will be decisively beaten for the foreseeable future..
THE CORIOLIS EFFECT
On Bullet Trajectory I talked about Coriolis Effect as a variable which affect the bullet flight both on the horizontal and the vertical plane of the trajectory. But what exactly is Coriolis Effect?
When talking about ballistics, the Coriolis Effect refers to the deflection on the trajectory of the bullet generated by the spinning motion of the Earth. Its effect is negligible at medium distances, but becomes important around 1000yds and beyond, especially because it can add to other minimal errors and keep you off target.
Coriolis Effect affects everything not firmly attached to the Earth’s surface. It affects fluids, like air and water, as well as floating and flying objects like ships, airplanes and… bullets.
Despite being associated with Coriolis, the phenomenon that actually affects the vertical component of the trajectory is called Eötvös Effect.
The rotation of the Earth generates a centrifugal force, the same that pushes you to the side when you make a sharp turn with your car. This force acts perpendicular to the Earth rotatory axis, adding or subtracting to the gravity force. When an object flies eastward, in the same direction of Earth’s rotation, centrifugal force acts opposite of gravity, pushing it away from the Earth’s surface. If the object flies westward, in the opposite direction of the Earth rotation, centrifugal force pushes the object toward the ground concurrently to gravity force. Thus, bullets fired to the east always fly a little higher, and, conversely, bullets fired to the west always travel somewhat low.
The amount of drop change is in function of
The linear velocity of a point on the Earth’s surface, and thus the amount of centrifugal force, is a maximum at the equator and decreases going toward the poles, where it is null.
Shooting direction, or azimuth – The amount of drop change is highest when shooting east or west, and as the trajectory angles north or south, the amount of drop change decreases, becoming null, as the angle points toward either pole.
The amount of centrifugal force is determined by the speed of the flying object.
Before, I mentioned that the vertical element associated with the Coriolis Effect is actually called the Eötvös effect. To give you an idea how the Eötvös effect alters a trajectory, here’s an example. Let’s say you’re firing a .308 175gr bullet, with a muzzle velocity of 2700fps, from latitude of 45°. The drop at 1000yds will be 392 inches, shooting either to the north or south (without error). Shooting with an azimuth of 90°, or eastward, the drop will be 388in. shooting with an azimuth of 270°, or westward, the drop will be 396in. In either case, there is a total change in drop of 4in. An easy assumption is to predict that, when shooting with an intermediate azimuth, that the drop change will be linear. This is incorrect. Instead of a 2in change for an azimuth of 45°, the error is a function of the sine of the azimuth angle. For those of you who don’t have a fondness for trigonometry, this essentially means that you have half the error at 30° rather than at 45°. Changes in latitude have a minimal effect, since at the equator, where the effect is greatest, the error would be 5in, only one inch more than the error we calculated at 45° latitude.
What is most affected by Coriolis Effect is the horizontal component of the bullet trajectory. Because of the Coriolis Effect, every moving object not connected to the ground is always deflected to right in the Northern Hemisphere, and always toward left in the Southern Hemisphere. The deflection is not east or west, but specifically to the right or left with reference to the shooting direction. It doesn’t matter in which direction you shoot; it is a function of latitude and average bullet speed. Its effect is maximum at the poles, and decreases as one moves toward the Equator, where it is minimal. The explanation of this phenomenon is more difficult than the explanation of Eötvös Effect, so I won’t go into it into detail.
Here’s an example of error due to Coriolis Effect: firing the same .308 175gr bullet at 2700fps muzzle velocity, from latitude of 45° in the Northern Hemisphere, the deflection at 1000yds will be of 3in to right. At the North Pole, where the effect is maximum, the deflection will be a little more than four inches. The deflection will be the same in the Southern Hemisphere, but it will be to the left, instead.
As you can see, these errors are subtle, even when shooting long distance. However, especially when combined with other potential error factors in your long distance shooting equation; it could make the difference between hitting and missing your target. If you have portable ballistic software, you can use it to calculate Coriolis for you at every distance. But, if you’re doing the math on your own, I wouldn’t start to take Coriolis into consideration unless shooting at 1,000 yards, or more.