Determining the distance to the target using available means. Distance meter on the ground. Methods for measuring distance. Determining distances by eye

Methods for determining distances on the ground and target designation

Methods for determining distances on the ground

Very often it is necessary to determine the distances to various objects on the ground. Distances are most accurately and quickly determined using special instruments (rangefinders) and rangefinder scales of binoculars, stereo scopes, and sights. But due to the lack of instruments, distances are often determined using improvised means and by eye.

Common methods for determining the range (distances) to objects on the ground include the following: by the angular dimensions of the object; by linear dimensions of objects; eye; by visibility (discernibility) of objects; by sound, etc.

Determining distances by the angular dimensions of objects (Fig. 8) is based on the relationship between angular and linear quantities. The angular dimensions of objects are measured in thousandths using binoculars, observation and aiming devices, a ruler, etc.

Some angular values ​​(in thousandths of the distance) are given in Table 2.

table 2

The distance to objects in meters is determined by the formula: , where B is the height (width) of the object in meters; Y is the angular magnitude of the object in thousandths.

For example (see Fig. 8):
1) the angular size of the landmark observed through binoculars (a telegraph pole with a support), the height of which is 6 m, is equal to the small division of the binocular reticle (0-05). Therefore, the distance to the landmark will be equal to: .

2) the angle in thousandths, measured with a ruler located at a distance of 50 cm from the eye, (1 mm is equal to 0-02) between two telegraph poles 0-32 (telegraph poles are located at a distance of 50 m from each other). Therefore, the distance to the landmark will be equal to: .

3) tree height in thousandths, measured with a 0-21 ruler (true tree height 6 m). Therefore, the distance to the landmark will be equal to: .

Determining distances by linear dimensions of objects is as follows (Fig. 9). Using a ruler located at a distance of 50 cm from the eye, measure the height (width) of the observed object in millimeters. Then the actual height (width) of the object in centimeters is divided by that measured by a ruler in millimeters, the result is multiplied by a constant number 5 and the desired height of the object in meters is obtained.

For example, a distance between telegraph poles equal to 50 m (Fig. 8) is closed on the ruler by a segment of 10 mm. Therefore, the distance to the telegraph line is:

The accuracy of determining distances by angular and linear values ​​is 5-10% of the length of the measured distance. To determine distances based on the angular and linear dimensions of objects, it is recommended to remember the values ​​(width, height, length) of some of them, given in table. 3.

Table 3

Determining distances by eye

Eye control is the easiest and fastest way. The main thing in it is the training of visual memory and the ability to mentally lay down a well-imagined constant measure on the ground (50, 100, 200, 500 meters). Having fixed these standards in memory, it is not difficult to compare with them and estimate distances on the ground.

When measuring distance by successively mentally setting aside a well-studied constant measure, one must remember that the terrain and local objects seem reduced in accordance with their distance, that is, when removed by half, the object will seem half as large. Therefore, when measuring distances, the mentally plotted segments (measures of terrain) will decrease according to the distance.

The following must be taken into account:
- the closer the distance, the clearer and sharper the visible object seems to us;
- the closer the object, the larger it seems;
- larger objects seem closer than small objects located at the same distance;
- an object of a brighter color appears closer than an object of a dark color;
- brightly lit objects seem closer to dimly lit ones that are at the same distance;
- during fog, rain, twilight, cloudy days, when the air is saturated with dust, observed objects seem further away than on clear and sunny days;
- the sharper the difference in the color of the object and the background against which it is visible, the more reduced the distances seem; for example, in winter a snow field seems to bring the darker objects on it closer;
- objects on flat terrain seem closer than on hilly terrain, distances defined across vast expanses of water seem especially shortened;
- folds of the terrain (river valleys, depressions, ravines), invisible or not fully visible to the observer, conceal the distance;
- when observing while lying down, objects seem closer than when observing while standing;
- when observed from bottom to top - from the base of the mountain to the top, objects seem closer, and when observed from top to bottom - further;
- when the sun is behind the soldier, the distance disappears; shines into the eyes - it seems larger than in reality;
- the fewer objects there are in the area under consideration (when observed through a body of water, a flat meadow, steppe, arable land), the smaller the distances seem.

The accuracy of the eye meter depends on the training of the soldier. For a distance of 1000 m, the usual error ranges from 10-20%.

Determination of distances by visibility (discernibility) of objects

With the naked eye, you can approximately determine the distance to targets (objects) by the degree of their visibility. A soldier with normal visual acuity can see and distinguish some objects from the following maximum distances indicated in Table 4.

It must be borne in mind that the table indicates the maximum distances from which certain objects begin to be visible. For example, if a serviceman saw a pipe on the roof of a house, this means that the house is no more than 3 km away, and not exactly 3 km. It is not recommended to use this table as a reference. Each serviceman must individually clarify this data for himself.

Table 4

Orientation by sounds

At night and in fog, when observation is limited or impossible at all (and in very rough terrain and in the forest, both at night and during the day), hearing comes to the aid of vision.

Military personnel must learn to determine the nature of sounds (that is, what they mean), the distance to the sources of sounds and the direction from which they come. If different sounds are heard, the soldier must be able to distinguish them from one another. The development of such an ability is achieved through long-term training (in the same way a professional musician distinguishes the voices of instruments in an orchestra).

Almost all sounds that indicate danger are made by humans. Therefore, if a soldier hears even the faintest suspicious noise, he should freeze in place and listen. If the enemy starts moving first, thereby giving away his location, then he will be the first to be detected.

On a quiet summer night, even an ordinary human voice in an open space can be heard far away, sometimes half a kilometer. On a frosty autumn or winter night, all kinds of sounds and noises can be heard very far away. This applies to speech, steps, and the clinking of dishes or weapons. In foggy weather, sounds can also be heard far away, but their direction is difficult to determine. On the surface of calm water and in the forest, when there is no wind, sounds travel a very long distance. But the rain greatly muffles the sounds. The wind blowing towards the soldier brings sounds closer and away from him. It also carries sound away, creating a distorted picture of the location of its source. Mountains, forests, buildings, ravines, gorges and deep hollows change the direction of sound, creating an echo. They also generate echoes and water spaces, facilitating its spread over long distances.

The sound changes when its source moves on soft, wet or hard soil, along the street, along a country or field road, on pavement or soil covered with leaves. It must be taken into account that dry soil transmits sounds better than air. At night, sounds are transmitted especially well through the ground. That’s why they often listen by putting their ears to the ground or tree trunks. The average range of audibility of various sounds during the day on flat terrain, km (in summer), is given in Table 5.

Table 5

To listen to sounds while lying down, you need to lie on your stomach and listen while lying down, trying to determine the direction of the sounds. This is easier to do by turning one ear in the direction from which the suspicious noise is coming. To improve hearing, it is recommended to apply bent palms, a bowler hat, or a piece of pipe to the auricle.

To better listen to sounds, you can put your ear to a dry board placed on the ground, which acts as a sound collector, or to a dry log dug into the ground.

Determining distances using the speedometer. The distance traveled by a car is determined as the difference between the speedometer readings at the beginning and end of the journey. When driving on hard-surfaced roads it will be 3-5%, and on viscous soil 8-12% more than the actual distance. Such errors in determining distances using the speedometer arise from wheel slip (track slippage), tire tread wear and changes in tire pressure. If you need to determine the distance traveled by the car as accurately as possible, you need to make an amendment to the speedometer readings. This need arises, for example, when moving in azimuth or when orienting using navigation devices.

The amount of correction is determined before the march. For this purpose, a section of the road is selected, which in terms of the nature of the relief and soil cover is similar to the upcoming route. This section is passed at marching speed in the forward and reverse directions, taking speedometer readings at the beginning and end of the section. Based on the data obtained, the average length of the control section is determined and the value of the same section, determined from a map or on the ground with a tape (roulette), is subtracted from it. Dividing the result obtained by the length of the section measured on the map (on the ground) and multiplying by 100, the correction factor is obtained.

For example, if the average value of the control section is 4.2 km, and the measured value on the map is 3.8 km, then the correction factor is:

Thus, if the length of the route measured on the map is 50 km, then the speedometer will read 55 km, i.e. 10% more. The difference of 5 km is the magnitude of the correction. In some cases it may be negative.

Measuring distances in steps. This method is usually used when moving in azimuth, drawing up terrain diagrams, drawing individual objects and landmarks on a map (scheme), and in other cases. Steps are usually counted in pairs. When measuring a long distance, it is more convenient to count steps in threes, alternately under the left and right foot. After every hundred pairs or triplets of steps, a mark is made in some way and the countdown begins again.

When converting the measured distance in steps into meters, the number of pairs or triplets of steps is multiplied by the length of one pair or triple of steps.

For example, there are 254 pairs of steps taken between turning points on the route. The length of one pair of steps is 1.6 m. Then

Typically, the step of a person of average height is 0.7-0.8 m. The length of your step can be determined quite accurately using the formula: , where D is the length of one step in meters; P is a person’s height in meters.

For example, if a person is 1.72 m tall, then his step length will be equal to:

More precisely, the step length is determined by measuring some flat linear section of terrain, for example a road, with a length of 200-300 m, which is measured in advance with a measuring tape (tape measure, range finder, etc.).

When measuring distances approximately, the length of a pair of steps is taken to be 1.5 m.

The average error in measuring distances in steps, depending on driving conditions, is about 2-5% of the distance traveled.

Determination of distance by time and speed. This method is used to approximate the distance traveled, for which the average speed is multiplied by the time of movement. The average walking speed is about 5, and when skiing 8-10 km/h.

For example, if a reconnaissance patrol skied for 3 hours, then it covered about 30 km.

Determination of distances by the ratio of the speeds of sound and light. Sound travels in the air at a speed of 330 m/s, i.e. approximately 1 km per 3 s, and light travels almost instantly (300,000 km/h). Thus, the distance in kilometers to the place of the flash of the shot (explosion) is equal to the number of seconds that passed from the moment of the flash to the moment when the sound of the shot (explosion) was heard, divided by 3.

For example, an observer heard the sound of an explosion 11 seconds after the flash. The distance to the flash point will be:

Determination of distances by geometric constructions on the ground. This method can be used to determine the width of difficult or impassable terrain and obstacles (rivers, lakes, flooded areas, etc.). Figure 10 shows the determination of the river width by constructing an isosceles triangle on the ground.

Since in such a triangle the legs are equal, the width of the river AB is equal to the length of the leg AC.

Point A is selected on the ground so that a local object (point B) on the opposite bank can be seen from it, and a distance equal to its width can be measured along the river bank.

The position of point C is found by approximation, measuring the angle ACB with a compass until its value becomes equal to 45°.

Another version of this method is shown in Fig. 10, b.

Point C is selected so that the angle ACB is equal to 60°.

It is known that the tangent of an angle of 60° is equal to 1/2, therefore, the width of the river is equal to twice the distance AC.

In both the first and second cases, the angle at point A should be equal to 90°.

Orientation by light very convenient for maintaining direction or for determining the position of an object on the ground. Moving at night towards a light source is most reliable. The distances at which light sources can be detected by the naked eye at night are given in Table 6.

Table 6

Target designation

Target designation is the ability to quickly and correctly indicate targets, landmarks and other objects on the ground. Target designation has important practical significance for controlling a unit and fire in battle. Target designation can be carried out either directly on the ground or from a map or aerial photograph.

When designating targets, the following basic requirements are observed: indicate the location of targets quickly, briefly, clearly and accurately; indicate goals in a strictly established order, using accepted units of measurement; the transmitter and the receiver must have common landmarks and firmly know their location, and have a uniform coding of the area.

Target designation on the ground is carried out from a landmark or in azimuth and range to the target, as well as by pointing the weapon at the target.

Target designation from a landmark is the most common method. First, the closest landmark to the target is named, then the angle between the direction to the landmark and the direction to the target in thousandths, and the distance of the target from the landmark in meters. For example: “Landmark two, forty-five to the right, then one hundred, there is an observer at a separate tree.”

If the transmitting and receiving target have observation devices, then instead of the distance of the target from the landmark, the vertical angle between the landmark and the target in thousandths can be indicated. For example: “Landmark four, thirty to the left, ten below - a combat vehicle in a trench.”

In some cases, especially when issuing target designation for unobtrusive targets, local objects located near the target are used. For example: “Landmark two, thirty to the right - a separate tree, further two hundred - ruins, twenty to the left, under a bush - a machine gun.”

Target designation by azimuth and range to the target

The azimuth of the direction to the appeared target is determined using a compass in degrees, and the distance to it in meters using binoculars (observation device) or by eye. Having received this data, they transmit it, for example: “Thirty-two, seven hundred - combat vehicle.”

Target designation by pointing a weapon at a target

Targets spotted on the battlefield must be immediately reported to the commander and their location correctly indicated. The target is indicated by verbal report or tracer bullets.

The report should be short, clear and precise, for example: “There is a wide bush straight ahead, a machine gun to the left.” “The second landmark, two fingers to the right, under the bush there is an observer.” When designating targets with tracer bullets, fire one or two short bursts in the direction of the target.

A person located in any area may need the ability to measure distances to certain objects, as well as determine the width and height of these objects. Such measurements can be better and more accurately carried out using special means (laser rangefinders, rangefinder scales of optical instruments, etc.), but these may not always be at hand. Therefore, in this situation, knowledge of “old-fashioned” time-tested methods will come to the rescue. These include:

• determining distances by eye
• by angular value
• determining distances using a ruler and handy objects
• by sound

Determining distances by eye

This method is the simplest and fastest. The decisive factor here is the ability to mentally lay out equal segments of 50, 100, 500 and 1000 m on the ground. These distance segments must be studied and well fixed in visual memory. The following features must be taken into account:

• on flat terrain and water, distances seem shorter than they actually are,
• hollows and ravines reduce the apparent distance,
• larger objects seem closer to smaller ones, being on the same line with them,
• all objects seem closer during fog, rain, cloudy days,
• brightly colored objects appear closer
• when viewed from the bottom up, the distances seem closer, and when observed from the top down, they appear larger,
• At night, luminous objects appear closer.

Distances of more than 1 km are determined with a greater error, reaching 50%. For experienced people, especially at short distances, the error is less than 10%. The eye sensor must be constantly trained in different visibility conditions, on different terrain. At the same time, tourism, mountaineering, and hunting play a huge positive role. This method is based on the concept of thousandths. The thousandth is a unit of measurement of distances along the horizon, and is 1/6000 of the horizon. The concept of a thousandth is accepted in all countries of the world, and is used to introduce horizontal corrections for the firing of small arms and artillery systems, as well as to determine distances and distances. Thousands are written and read. way:

• 1 thousandth 0-01, read as zero, zero one,
• 5 thousandths 0-05, read as zero, zero five,
• 10 thousandths 0-10, read as zero, ten,
• 150 thousandths 1-50, read as one, fifty,
• 1500 thousandths 15-00, read as fifteen, zero zero.

The use of this method is possible if one of the linear quantities of the object is known - width or height. The distance to the object is determined by the following. formula: D = (Bx1000) / Y, where D is the range to the target B is the width or height of the object in meters Y is the angular value in thousandths. In order to determine the angular value, you need to know that a segment of 1 mm distant 50 cm from the eye corresponds to an angle of 2 thousandths (0-02). Based on this, there is a method for determining distances using a ruler:

• extend the ruler with millimeter divisions to a distance of 50 cm,
• determine how many divisions on a ruler the width or height of an object fits into,
• multiply the resulting number of millimeters by 2 and substitute it into the above formula.

It is even more convenient to use a caliper for these purposes, which can be shortened for compactness.

Example: The height of the telegraph pole is 6 m; measuring on a ruler will take 8 mm (16 thousandths, i.e. 0-16), therefore the distance to the pole will be (6 × 1000)/16 = 375 m

There is also a simpler formula for determining distance using a ruler:
L = (height or width of the object in cm / number of millimeters on the ruler) x 5

Example: the growth figure has a height of 170 cm and covers 2 mm on the ruler, therefore the distance to it will be: (170 cm / 2 mm) x 5 = 425 m

Determining distances using a ruler and handy objects

Linear dimensions of common objects

In the absence of a ruler, angular values ​​can be measured using improvised objects, knowing their linear dimensions. This could be, for example, a matchbox, a match, a pencil, a coin, cartridges, fingers, etc. For example, a matchbox has a length of 45 mm, a width of 30 mm, a height of 15 mm, therefore if it is pulled out to a distance of 50 cm, its length will correspond to 0-90, width 0-60, height 0-30.

Determining distances by sound

A person has the ability to capture and distinguish sounds of various natures, both in the horizontal and vertical planes, which makes it possible to very successfully determine offhand distances to sound sources. Hearing, like the eye, must be constantly trained.

• Hearing works with full efficiency only when the psyche is completely calm.
• Lying on your back worsens auditory orientation, while lying on your stomach improves
• Green color improves hearing
• A piece of sugar placed under the tongue significantly improves night vision and hearing, since glucose is necessary for the functioning of the heart, brain, nervous system, and therefore the senses.
• Sounds are clearly audible in open areas, especially water, in calm weather
• Audibility worsens in hot weather, against the wind, in the forest, in reeds, on loose grass.

Average audibility range of various sources

Preparing binoculars for use

1. Remove the binoculars from the case.

2. Inspect the optics and housing.

3. Rotate the eyepieces (2) to set the required diopter value on the diopter scale (5).

4. Place the monoculars at the base of the eyes so that there is one field of view.

Measuring the range to targets using the binocular reticle

1. Point the binocular reticle at the target and determine its angular value.

2. Knowing the height or width of the target, determine the range to the target using the thousandth formula:

where D is the range to the target,

B – height or width of the target,

Y is the angular magnitude of the target in thousandths.

Example(Fig.3):

the tank is “placed” between two small divisions, which corresponds to 0-10. The average height of the tank is 2.7 m. We determine the range to the tank if U = 0-10, B = 2.7 m

.

The range to the tank is 270 meters.

NIGHT BINOCULARS BN-1

Night binoculars BN-1 are designed for observing the battlefield, studying the terrain and conducting reconnaissance in natural night light conditions.

Technical characteristics of BN-1

Identification range in natural night light……200m.

Magnification 3.2 x.

Field of view angle9°±30.

Battery voltage 8.3-8.8v.

Continuous operation time of the device (without replacing the battery):

At a temperature of + 20 degrees C7h;

At a temperature of 40 degrees C3h;

At a temperature of + 40 degrees C5h.

Device weight:

In stowed position 3.5 kg;

In working position 1.6 kg.

We often hear that shooters simply do not know how to determine the distance to the target (target) at which they need to shoot. And this despite the fact that an optical sight is installed on the rifle or shotgun (carbine). In general, the topic of optical sights is very common in questions on forums and letters from readers. The main issues are reticles and distances to the object of observation. Which reticle is best for long range shooting? Why big ones? Yes, because at a distance of 10 to 20 m it is easier to use a red dot sight. I decided to organize some information regarding optics and distance.

A simple method for determining the distance to an object

In the picture below you can see the aiming reticle Rangefinder, or as it is popularly called - “crossbow net”. Sights with this type of reticle have become very popular among owners of weapons with optical sights. A convenient scale for calculating distances and at the same time auxiliary crosshairs allow you to very accurately calculate the distance to the target, making certain adjustments. The figure clearly shows how you can determine the distance to a target using the example of a 4x32 optical sight.

Visual determination of the distance to the target using an optical sight
(Rangefinder reticle, or crossbow reticle)

It is worth noting that the setup and preliminary calibration of each sight must be carried out separately. This should be done as follows:
- take a “standard” with a vertical and horizontal dimension of 50 cm (for example, a cardboard box),
- set the scope magnification to 4 (if you have a scope with variable magnification) and look at the “standard” through the optical sight from a distance of 30 m. Usually at this distance 0.5 meters of width is placed between the curves at the level of the central crosshair.

If the “standard” does not fit between the curves or, on the contrary, is much smaller, then you need to change the distance to the target until you achieve the desired result. Remember this distance, or better yet, make a note to yourself so that later, when needed, you can quickly calculate the distance to the target.

In the same way, we find the distances corresponding to all other aiming marks on the reticle. After this, you can begin to zero in the sight. “Why not the other way around?” - you ask. Yes, because it is easier to sight the sight at already known distances. Now, looking at your hunting object through an optical sight, you will know exactly the distance to the target.

Such sights can be installed on air guns and firearms.

To approximately determine the distance, a sniper or shooter can use the following simplest methods.

An eye-based method for determining the distance to a target

To hit the target with the first shot, you need to know the distance to it. This is necessary to correctly determine the magnitude of corrections for side wind, air temperature, atmospheric pressure and, most importantly, to install the correct sight and select the aiming point.

The ability to quickly and accurately determine the distance to stationary, moving, and emerging targets is one of the main conditions for the successful work of a sniper.

Rice. Proportional perception of the target by the sniper with the reticle of the PSO-1 sight for the development of automatic skills in determining the range

The main one, the simplest and fastest, most accessible to a sniper in any combat situation. However, a sufficiently accurate eye is not acquired immediately; it is developed through systematic training carried out in various terrain conditions, at different times of the year and day. To develop your eye, you need to more often practice estimating distances by eye, necessarily checking them in steps and on a map or in some other way.

First of all, you need to learn to mentally imagine and confidently distinguish several distances that are most convenient as standards on any terrain. You should start training with short distances (10, 50, 100 m). Having mastered these distances well, you can move successively to larger ones (200, 400, 800 m) up to the maximum range of actual fire from a sniper rifle. Having studied and consolidated these standards in visual memory, you can easily compare with them and evaluate other distances.

During such training, the main attention should be paid to taking into account side effects that affect the accuracy of the visual method of determining distances:
1. Larger objects seem closer than small ones located at the same distance.
2. Objects that are visible more sharply and clearly seem to be closer together, therefore:
- objects of bright colors (white, yellow, red) seem closer than objects of dark colors (black, brown, blue),
- brightly lit objects seem closer to dimly lit ones that are at the same distance,
- during fog, rain, at dusk, on cloudy days, when the air is saturated with dust, observed objects seem further away than on clear sunny days,
- the sharper the difference in the color of objects and the background against which they are visible, the more reduced the distances to these objects seem; for example, in winter, a snow field seems to bring all the darker objects on it closer.

3. The fewer intermediate objects are between the eye and the observed object, the closer this object seems, in particular:
- objects on level ground seem closer,
- distances defined through vast open water spaces seem especially shortened; the opposite shore always seems closer than in reality,
- folds of the terrain (ravines, hollows) crossing the measured line seem to reduce the distance,
- when observing while lying down, objects seem closer than when observing while standing.

4. When observed from bottom to top, from the bottom of the mountain to the top, objects appear closer, and when observed from top to bottom, they appear further away.

Visibility of objects at different distances:

Determining the distance to the target by angular dimensions

Determining the distance to a target by angular dimensions is possible if the observable linear value (height, width or length) of the object to which the distance is determined is known. The method comes down to measuring the angle in thousandths at which this object is visible.

The thousandth is 1/6000 part of the circular horizon, increasing in width in direct proportion to the increase in the distance to the reference point, which is the center of the circle. For those who have a hard time understanding, remember that the thousandth is in distance:

100 m = 10 cm,

200 m = 20 cm,

300 m = 30 cm,

400 m = 40 cm, etc.

Knowing the approximate linear dimensions of a target or landmark in meters and the angular magnitude of this object, you can determine the distance using the thousandth formula: D = (H x 1000)/U,
Where D- distance to target
1000 - a constant, unchangeable mathematical quantity that is always present in this formula
U- the angular magnitude of the target, that is, to put it simply, how many one-thousandth divisions on the scale of an optical sight or other device will the target occupy
IN- metric (that is, in meters) known width or height of the target.

For example, a target is detected. It is necessary to determine the distance to it. What are the actions?
1. Measure the target angle in thousand.
2. The size of the object located next to the target in meters, multiply by 1000
3. Divide the result obtained by the measured angle in thousand.

The metric parameters of some objects are:

The scales of open sights, optical sights and optical instruments available in service are graduated in thousandths and have a division value:

Thus, to determine the distance to an object using optics, it is necessary to place it between the scale divisions of the sight (device) and, having found out its angular value, calculate the distance using the above formula.

Example, you need to determine the distance to the target (chest or height target), which fits into one small side segment of the scale of the PSO-1 optical sight.

Solution, the width of the chest or height target (full-length infantryman) is 0.5 m. According to measurements using PSO-1, the target is covered by one division of the lateral correction scale, i.e. angle 1 thousandth.
Hence: D=(0.5 x 1000)/1=500m.

Measuring angles using improvised means

To measure angles with a ruler, you need to hold it in front of you, at a distance of 50 cm from the eye, then one of its divisions (1 mm) will correspond to 0-02.
The accuracy of measuring angles using this method depends on the skill in placing the ruler exactly 50 cm from the eye. You can practice this using a rope (thread) of this length.
To measure angles with improvised objects, you can use your finger, palm or any small improvised object (matchbox, pencil, 7.62 mm sniper cartridge), the dimensions of which in millimeters, and therefore in thousandths, are known. To measure the angle, such a measure is also placed at a distance of 50 cm from the eye, and from it the desired angle value is determined by comparison.

The angular dimensions of some objects are:

Having acquired skills in measuring angles, you should proceed directly to determining distances based on the measured angular dimensions of objects.
Determining distances by the angular dimensions of objects gives accurate results only if the actual dimensions of the observed objects are well known, and angular measurements are made carefully using measuring instruments (binoculars, stereo scopes).

Application of the “thousandth” formula in shooting practice

To determine firing distances using the “thousandths” formula, it is necessary to know exactly in advance the width or height of the object (target) to which the distance is being determined, determine the angular value of this object in thousandths using available optical instruments, and then calculate the distance using the formula, where:

D is the distance to the object in meters;
Y is the angle at which the object is visible in thousandths;
B is the metric (that is, in meters) known width or height of the target.

1000 is a constant, unchangeable mathematical value that is always present in this formula.

When determining the distance in this way, you need to know or imagine the linear dimensions of the target, its width or height. The linear data (sizes) of objects and targets (in meters) in infantry combined arms practice are accepted as follows.

For example, you need to determine the distance to the target (chest or height target), which fits into two small side segments of the scale of the PSO-1 optical sight, or is equal to the thickness of the aiming stump of the PU sight, or is equal to the thickness of the front sight of an open rifle sight. The width of the chest or height of the target (full-length infantryman), as can be seen from the table. 6, is equal to 0.5 m. According to all measurements of the above sighting devices (see below), the target is covered by an angle of 2 thousandths. Hence:

But the width of a live target may be different. Therefore, a sniper usually measures the width of the shoulders at different times of the year (by clothing) and only then accepts it as a constant value. It is necessary to measure and know the basic dimensions of the human figure, the linear dimensions of the main military equipment, vehicles and everything that can be “attached” to on the side occupied by the enemy. And at the same time, all this should be viewed critically. Despite laser rangefinders, the determination of ranges in combat practice of the armies of all countries is carried out according to the above formula. Everyone knows about it and everyone uses it, and therefore they try to mislead the enemy. There have been numerous cases when telegraph poles were secretly increased by 0.5 m at night - during the day this gave the enemy an error in calculating the range of 50-70 meters of shortfall.

Angular values ​​in thousandths of available objects and devices

To measure the angular values ​​of targets in thousandths, the most commonly used objects are used, which in combat practice are often at hand. Such items and means are parts of open sights, sighting threads, marks, reticles of optical sights and other optical devices, as well as everyday items that are always available to a soldier - cartridges, matches, ordinary scale metric rulers.

As mentioned earlier, the width of the front sight covers an angle of 2 thousandths in the projection onto the target. The height of the front sight covers 3 thousandths. The base of the sight - the width of the slot - covers 6 thousandths.

As mentioned earlier, the width of the aiming stump covers an angle of 2 thousandths in the projection onto the target. The horizontal threads cover the angles in their thickness by also 2 thousandths. Sight base

A - the distance between the threads - covers 7 thousandths.

For PSO-1:
A - main square for shooting up to 1000 m,
B - three additional squares for shooting at distances of 1100, 1200, 1300 m;
B - the width of the lateral correction scale from 10 to 10 thousandths corresponds to 0-20 (twenty thousandths),
G - from the center (main square) right-left to the number 10 corresponds to 0.10 (ten thousandths) The height of the extreme vertical mark at the number 10 is 0.02 (two thousandths);
D - the distance between two small divisions is 0.01-1 (one thousandth), the height of one small mark on the lateral correction scale is 0.01 (one thousandth);
E - numbers on the rangefinder scale 2, 4, 6, 8, 10 correspond to distances of 200, 400, 600, 800 and 1000 m;
F - the number 1.7 shows that at this level of the height scale the average human height is 170 cm.

Measurements in thousandths of the binocular and periscope reticle:
- from a small risk to a large risk (short distances), an angle of 0.05 (five thousandths) is covered;
- from large risk to large risk, an angle of 0.10 (ten thousandths) is covered.

The height of the small risk is 2.5 thousandths.
The height of the large risk is 5 thousandths.
Cross bars - 5 thousandths.

When using improvised means to determine angular values, they are placed at a distance of 50 cm from the eye. This distance has been verified over many decades. At a distance of 50 cm from the eye, the rifle cartridge and matches close the angles indicated below in projection onto the target.

1 centimeter of an ordinary scale ruler (better if it is made of transparent material) at a distance of 50 cm from the eye covers an angle of 20 thousandths; 1 millimeter, respectively, 2 thousandths.

Prudent shooters determine in advance a goniometric distance of 50 cm for possible determination of distances based on the angular values ​​of available objects. Usually for this purpose they measure 50 cm on the rifle and mark it.