What does caliber 7.62 mean. Caliber of small arms, its measurement and designation in different countries

Caliber is the main parameter of both weapons and cartridges. Figuratively speaking, the caliber is the size. For example, caliber 9x18. What does this mean? This means the length of the cartridge case is 18mm, the diameter of the cartridge case (where the bullet is located) is 9mm. Or 5.45x39: means the bullet diameter is 5.45mm and the case length is 39mm.

Don't get confused by the definitions:

A sleeve is an object where a charge of gunpowder and a primer are located (a device that ignites gunpowder on impact)

A bullet is an object made of lead, steel or other materials, which, after being fired, flies out of the weapon and hits the target.

A cartridge is a combination of a cartridge case and a bullet, that is, a bullet installed in a cartridge case.

The main ammo and weapons that you will meet.

1. Caliber 9x18

These are PM pistols (Makarov pistol), the most common pistol in Russia, Ukraine, Belarus and other countries former USSR. This pistol has been in service for more than 50 years with all services: police, security, armed forces, etc. With this gun, you can confidently hit a person at a distance of up to 50m in unprotected parts of the body.

Also, cartridges of this caliber are used in some domestic submachine guns and special-purpose pistols. I will not talk more about this weapon, since it is not very widespread, however, you can get acquainted with this weapon in the games mentioned above.

2. Caliber 9x19

It is the most common pistol caliber in Europe and the USA. The most common pistols of this caliber are Glock -19. Also, many submachine guns, both foreign and domestic, were made under this cartridge. Cartridges of this caliber have high power, so they are guaranteed to hit an unprotected person at a distance of 100-150m, and at a distance of up to 50m they can also penetrate light body armor.

3. Caliber 5.45x39

This is an automatic cartridge of domestic production. Currently, it is in service with Russia, Ukraine, Belarus and other countries. That is, the most popular cartridge in the army, which is also called the "five". It is used for Kalashnikov assault rifles and machine guns of different series: Ak-74, Ak-74M, Ak-74MR, AKS, Ak-107, Ak-12, RPK-74, etc. Cartridges of this caliber can be guaranteed to hit an unprotected person at a distance of up to 1-1.5 km, and at a distance of up to 500-700 m they can penetrate light and medium-protected bulletproof vests. The advantages of these cartridges: they are dofiga)), are everywhere; light weight, can carry a lot; normal penetration at medium range. Cons: the bullets of these cartridges are relatively light, when shooting in the forest at long distances - the bullets can deviate from the branches of the bush. Also, at short distances, when hitting an unprotected human body, they pierce it through and through, which does not guarantee a quick death of the enemy, unless, of course, a hit to the head is meant.

4. Caliber 5.56x45 (NATO)

This is the main caliber of all American and NATO assault rifles and rifles. The number of types of these rifles is so great that it makes no sense to write about them. It is important to just remember: if our enemy is a fighter of the NATO bloc or an American, with a guarantee of 95% it can be argued that he will have a weapon for this caliber in his hands. This cartridge is slightly more powerful than our "five", otherwise the parameters are virtually the same.

5. Caliber 7.62x39

This is the caliber domestic weapons, which was in the days of the USSR. But also this caliber is now extremely widespread in Arab and Latin American countries, as well as around the world (and here too) as cartridges for hunting weapons. The most common weapons for this cartridge are:

Legendary Ak47, AKM and their modifications

Modern Ak-103, Ak-104 and Ak-12

Kalashnikov light machine guns

Saiga civilian carbines and others.

Cartridges of this caliber have a very powerful shock-dynamic force: if you hit the enemy’s hand in close combat, it will most likely be torn off. Also, this cartridge, in close combat, can confidently pierce any body armor and helmets. In case of war, having an Ak-103 + optics + a large supply of cartridges of this caliber on hand is the height of dreams and aspirations.

6. Caliber 7.62x51

These are "lethal" NATO cartridges. They are most often used in sniper rifles, as well as in machine guns. This caliber is also used in our country, for example, in the new Ak-12 assault rifle, as well as in some machine guns. I am attaching a photo, for comparison, on it (from left to right) 7.62x51, 5.56x45 and a finger battery. The power of this caliber is very high, and therefore it is used in the NATO sniper weapon, and if you get under fire from a machine gun of this caliber, then .... you understand.

The caliber of a weapon is, along with the length of the barrel, one of the most important characteristics of a firearm, this fully applies to hunting smooth-bore weapons.

The caliber of a shotgun is the diameter of its bore. The word caliber is of Arabic origin, derived from the word "galib", which means "form".

Some hunters consider the classic double-barreled shotguns with horizontal barrels to be the best shotguns, the most common among them among our hunters: IZH-54, IZH-58,.

Domestic semiautomatic devices, are very popular. AT last years foreign-made 12-gauge shotguns have become very popular, and .

Both of these calibers are not intended for hunting, they are used for recreational shooting and for self-defense purposes.

What caliber is best for hunting

All novice hunters, when buying their first gun, are interested in the question of what caliber they should choose. We will immediately warn that there is no unambiguous question on this question.

The choice of caliber depends on what game is supposed to be hunted, in what way, at what distance.

In caliber selection, hunters have strong personal preferences that outweigh any logical arguments in favor of one caliber or the other. The choice in any case should be reasonable, you should not go for a bear with a 410 caliber gun, it cannot end in anything good.

In our opinion, the most correct caliber for a beginner hunter is 12. It is the most versatile. widely available in stores. Also, the choice of cartridges for him is the widest.

Caliber(from lat. qua libra — how much per pound) - the diameter of the bore along the rifling or fields; one of the main quantities that determine the power of firearms.

The caliber is determined by smoothbore weapons by the inner diameter of the barrel, for a rifled one - by the distance between opposite fields of rifling (in the countries of the former USSR) or by the distance between the bottom of opposite rifling (NATO), for shells (bullets) - by the largest diameter. Guns with a tapered barrel are characterized by input and output calibers.

Caliber of rifled small arms

rifled caliber small arms in countries using the English system of measures, it is measured in fractions of an inch: in the USA - in hundredths (0.01 inches), in the UK - in thousandths (0.001 inches). In the record, the zero of the integer part of the number and the designation of the unit of measure (inch) are omitted (while in English-speaking countries a dot is used as a decimal separator): .45 , .450 . In Russian texts, traditional English and American calibers are written in the same way (with a dot, not a comma, the decimal separator adopted in Russia): cal.45, cal.450; in colloquial speech: forty-five caliber, four hundred and fifty caliber.

In countries that use the metric system of measures (in particular, in Russia), the caliber is measured in millimeters; in the designation, the sleeve length is added through the multiplication sign: 9×18 mm. It should be borne in mind that the length of the sleeve is not a characteristic of the caliber, but a characteristic of the cartridge. With the same caliber, cartridges can be of different lengths. A similar digital record is used mainly for army cartridges in the West. For civilian cartridges, the name of the company or the special characteristic of the cartridge is usually added to the caliber: .45 Colt, .41 S&W, .38 Super, .357 Magnum, .220. There are also more complex designations, for example, several designations of the same cartridge: nine millimeters, browning, short; three hundred and eighty, auto; nine by seventeen. The above state of affairs is due to the fact that almost every arms company has its own patented cartridges of different characteristics, and a foreign cartridge accepted for service or civilian circulation receives a new designation.

In Russia until 1917 and in a number of other countries, the caliber was measured in lines. One line is equal to 0.1 inches (more precisely, 0.254 cm or 2.54 mm). In modern speech, the name “three-line” has taken root, which literally means a rifle of the 1891 model of the year (Mosin system) of a caliber in three lines.

In some countries, the distance between the rifling fields (the smallest bore diameter) is considered the caliber, in others - the distance between the rifling ( largest diameter). As a result, with the same caliber designations, the diameters of the bullet and the bore are different. Examples are 9x18 Makarov and 9x19 Parabellum. Makarov has 9 mm - the distance between the fields, the bullet diameter is 9.25 mm. In Parabellum, the distance between the grooves is 9 mm, respectively, the bullet diameter is 9.02 mm, and the distance between the fields is 8.8 mm.

Small arms caliber classification:

• small-caliber (less than 6.5 mm),
• normal caliber (6.5-9.0 mm),
• large-caliber (9.0-20.0 mm).

Caliber up to 20 mm - small arms, over 20 mm - artillery

As a rule, small arms differ from artillery weapons by the type of ammunition. Small arms are designed to fire bullets, while artillery systems fire projectiles. At the same time, for rifled firearms, the main difference between bullets and projectiles as ammunition is the fact that the bullets, when passing through the bore, cut into the rifling with their shell. This creates a torque that increases the stability of the bullet in flight. The projectile, when fired, is given rotation with the help of leading belts (made from materials of less hardness than the shell of the shell of the projectile). However, this is not the only difference that exists and is not applicable to all types of artillery and small arms weapon systems.

The most common calibers for pistols, rifles and assault rifles are:

• .577 (14.7 mm) - the largest of the series, the revolver "Eley" (Great Britain);
• .50 (12.7 mm), used for heavy machine guns and sniper rifles;
• .45 (11.43 mm) - the "national" caliber of the United States, the most common in the Wild West; in 1911 self-loading pistol Colt M1911 of this caliber entered service with the army and navy and, repeatedly upgraded, served until 1985, when armed forces The USA switched to 9 mm for the Beretta 92, which is still used in civilian circulation;
• .40 (10.2 mm) - a relatively new pistol caliber; provides better efficiency, for which he received great popularity in the US law enforcement agencies;
• .38; .357 (9 mm), which is currently considered the best for short-barreled weapons (less - the cartridge is "weak", more - the gun is too bulky and heavy, strong recoil);
• .30 (7.62 mm) - caliber of ammunition for the Nagant revolver and TT pistol, Mosin rifle, AK assault rifle, sniper rifle SVD;
• .22 (5.6 mm) - caliber of ammunition for the TOZ-8 rifle (TOZ-10, TOZ-12);
• .223 (5.56 mm) - M16 automatic rifle ammunition caliber;
• 5.45 mm - caliber of ammunition for the AK-74 assault rifle;
• 2.7 mm - the smallest serial caliber; was used in the Hummingbird pistol of the Franz Pfannl system (Austria).

Caliber of a smoothbore hunting weapon

For smoothbore hunting rifles, calibers are measured differently: the caliber number means the whole number of round bullets that can be cast from 1 English pound of lead (453.59 g). In this case, the bullets must be spherical, identical in mass and diameter, which is equal to the inner diameter of the barrel in its middle part. The smaller the barrel diameter, the more bullets are produced from a pound of lead. Thus, the twentieth gauge is less than the tenth, and the sixteenth is less than the twelfth.

Caliber designation	Designation variant	Barrel diameter, mm
36	.410	10—10,2
32	.50	12,7
28	—	13,8
24	—	14,7
20	—	15,6
16	—	16,8
12	—	18,5
10	—	19,7
8	—	21,2
4	—	26,5

You can also use the formula for determining the caliber (K) by the diameter of the barrel (D, cm): K \u003d (453.6 * 6) / (Pi * D ^ 3 * 11.3415) ~= 76.3842 / D ^ 3.

In the designation of the caliber of cartridges for smoothbore weapons, as in the designation of cartridges for rifled weapons, it is customary to indicate the length of the sleeve, for example: 12/70 - cartridge 12 caliber with a sleeve 70 mm long. Most common case lengths: 65, 70, 76mm (Magnum); along with them there are 60 and 89 mm (Super Magnum).

The most widespread in Russia are hunting rifles of 12 gauge. There are (in descending order of prevalence) 16, 20, 24, 28, 32, 36 (.410), and the distribution of 36 caliber (.410) is due solely to the release of Saiga carbines of the corresponding caliber.

The actual diameter of the bore of a given caliber depends, firstly, on the specific manufacturer and, secondly, on drilling for a certain type of sleeve: metal or plastic (folder). For example, a 12-gauge barrel drilled for a folder (plastic) sleeve has a bore diameter of 18.3 mm, while a bore drilled for a metal one is 19.4 mm. In addition, we should not forget that the barrel of a shotgun hunting weapon usually has different kind chokes, through which not any bullet of its caliber can pass without damage to the barrel, so in many cases the body of the bullet is made according to the diameter of the choke and is equipped with centering belts that are easily crushed when passing through the choke. It should be noted that the common caliber of signal pistols - 26.5 mm - is nothing more than the 4th hunting caliber.

Caliber- the diameter of the barrel bore of a firearm, as well as the diameter of the projectile (bullet), this is one of the main quantities that determine the power of a firearm.

The caliber is determined for smooth-bore weapons by the inner diameter of the barrel, for rifled weapons - by the distance between opposite fields of rifling, for shells (bullets) - by the largest cross section. Guns with a tapered barrel are characterized by input and output calibers.

It is customary to measure the caliber of a hunting rifle not in millimeters, but by the number of spherical bullets that can be cast for a given gun from one English pound of lead, which is equal to 456 grams. Therefore, the smaller the digital designation of the caliber of the gun, the larger its caliber in the millimeter system.

Based on the definition of what is the caliber of a hunting smoothbore gun, i.e. that the nominal caliber is the number of round (ball) bullets cast from one pound (in English weight units) of pure lead, exactly corresponding to the hole of the receiver tube, then the normal weight of a shot shell by caliber is determined from the formula: C \u003d 454 / K (g), where C is the weight of the projectile in grams, 454 (more precisely - 453.6 g) is the weight equivalent of one English pound of pure lead in grams and K is the caliber of the gun in par value (10, 12, 16, 20, etc.).

From the above formula, the normal weight of the projectile along the diameter of the bore for 24 caliber will be: C \u003d 454/24 \u003d 18.9 (g), or rounded 19 g. Deviations of the weight of the projectile, determined by the formula, by +1.0 g. Considering However, that guns are made significantly lighter than required by the weight of a normal caliber projectile, it is necessary to check the weight of the projectile by the weight of the gun as a whole. It has been established from practice that at average initial projectile speeds from 350 to 375 m / s, the recoil will be tolerable if the weight of the projectile is within: for 12 gauge - from 1/100 to 1/94 total weight shotguns, for 16 gauge - 1/100, for 20 gauge - 1/112, for 24 gauge - 1/122, for 28 gauge - 1/136 and for 32 gauge - 1/148 of the total weight of the gun. Thus, with a 2.5 kg gun weighing 2.5 kg, the weight of the projectile will be 20.5 g. From this it can be seen that the weight of this gun corresponds to its caliber. In the production of domestic guns, it most often turns out that the weight of the gun significantly exceeds what should be according to its caliber, and the weight of the projectile, determined by the weight of the gun, will be significantly greater than that which was determined by the caliber of a round bullet. "In this In this case, the normal weight of the projectile, obtained from the caliber of the gun, and not from its weight, should be used.If the weight of the projectile, determined from the weight of the gun, is less than that determined from the caliber, then in this case one should stop at the projectile found from the weight of the gun. In other words, in all cases, take the weight of the projectile, which will be less.

In conclusion, it should be noted that, having made the indicated calculation and verification for a given gun, they stop at the resulting weight of the projectile for the entire time of its existence with a given hunter. All the desired changes in gun action are achieved only by changing the weight of gunpowder and the way the cartridges are loaded.

Caliber of rifled small arms

The caliber of rifled small arms is indicated in the USA, Great Britain and a number of other countries in fractions of an inch (.308 Winchester; in the USA - in hundredths (0.45 inches), in the UK - in thousandths (0.450 inches). When writing, zero and a comma are replaced by point, and "cal." is used instead of "inch" or omitted altogether (.45 cal.; .450 cal.) In colloquial speech, they say: "forty-five caliber", "four hundred and fifty caliber."

In other countries, it is measured in millimeters - 9 × 18 (the first number is the caliber, the second is the length of the sleeve in millimeters). Here it must be borne in mind that the length of the sleeve is not a characteristic of the caliber, but a characteristic of the cartridge. With the same caliber, cartridges can be of different lengths. It should also be borne in mind that such a "digital" recording is used mainly for army cartridges in the West. For civilian cartridges, the name of the company or model of weapon is usually added to the caliber, for example, the forty-fifth Colt, thirty-eighth Magnum. There are also more complex designations, for example, nine millimeters Browning is short, which is also the three hundred and eightieth car. The above description is due to the fact that almost every arms company has its own patented cartridges of different characteristics. In Russia (formerly in the USSR), the nomenclature of cartridges is unified, therefore it is widely used: 9 mm, 7.62 mm, 5.45 mm, 5.6 mm.

In Russia until 1917 and in a number of other countries, the caliber was measured in lines. One line = 0.1 inch = 2.54 mm. In modern vocabulary, the name "three-line" has taken root, which literally means "a rifle of the Mosin system with a caliber of three lines."

In some countries, the caliber is the distance between the rifling fields (the smallest bore diameter), in others, the distance between the rifling bottoms (the largest diameter). As a result, with the same caliber designations, the diameters of the bullet and the bores are different. Examples are 9x18 Makarov and 9x19 Parabellum.

Makarov has 9 mm - the distance between the fields, the bullet diameter is 9.25 mm.
In Parabellum, the distance between the bottoms is 9 mm, respectively, the diameter of the bullet is 9 mm, and the distance between the fields is 8.8 mm.

Agreed buckshot

About agreed buckshot:
Calculation of the diameter of the agreed buckshot is calculated according to the following formula:
Buckshot diameter = n * bore diameter at the muzzle.
Where:
n - constant depending on the number of buckshot in the layer
if buckshot 3 - n = 0.46;
4 - n = 0.41;
5 - n = 0.37.
With 7 buckshots in the layer, the formula takes the form
Buckshot diameter = diameter of the bore at the muzzle / 3.

The universal formula for calculating the diameter of the bore:
3–(76500/K)
Where:
K - caliber expressed in round bullets.

Formulas that may be needed when choosing a gun

1. Balance indicator.
By the balance of a gun, it is customary to mean the location of its center of gravity relative to the breech cut of the barrels, when the gun is assembled and the barrels are closed. A well-balanced gun has a center of gravity located 40-45 mm from the breech, large-scale - 65, 75 mm. The formula itself:

Pb = Tue / Sun
where: Vp - the total mass of the gun.
Sun is the mass of trunks without forearm.

The balance indicator should be in the limit:
from 2 to 2.3 - for double-barreled smoothbore hunting rifles
from 1.8 to 1.96 - for three-barreled combined hunting rifles
from 1.75 to 1.8 - for double-barreled rifled hunting fittings, rifles and carbines

2. Planting coefficient

The agility of a gun is called its agility, or ease of handling. It depends on the correct distribution of the mass of the gun along the main nodes (barrel with forearm and receiver with butt), and in the nodes themselves on the distribution of mass closer to the center of gravity of the entire gun, and not to its ends.
Kp = Vk.p. / (Sun+Sun)
where: Vk.p. - weight of the receiver with a butt
Sun - weight of trunks
Vts - the mass of the forearm.
For guns of excellent quality, Kp is equal to 1, for guns with light barrels it is more than 1, for heavy ones it is less than 1.

When buying a gun, it should be borne in mind that its mass should be a certain part of the mass of the shooter:
up to 1/21 from 50-55 kg;
up to 1/22 from 60-65 kg;
up to 1/23 from 70-75 kg;
up to 1/24 from 80-85 kg;
up to 1/25 from 90-95 kg;
up to 1/26 from 100 kg and above

As the mass of the gun increases, the shooter will usually get tired.

Formulas that may be required when sighting a gun

1. Projectile ratio.
The weight of the projectile can be calculated as follows:
A) from the weight of the gun Projectile weight \u003d gun weight / projectile coefficient
The projectile coefficient for 12 gauge is in the range from 94 to 100
For example, for a gun weighing 3.4 kg, the minimum weight of the projectile will be 34 grams (3400/100), the maximum - 36.2 (3400/94) grams.
B) the weight of the projectile by caliber. As you know, the caliber of a smoothbore weapon is the number of round bullets that can be made from 1 pound of lead. Thus, the weight of the projectile will be equal to the result of dividing the mass of the pound by the caliber. At the same time - 1 English pound = 453.592 g, 1 Trinity pound = 373.241 g, 1 French pound = 489.5 g, one Russian pound - 409.512 g. In principle, the standard was the English pound, but I give all types, since the numbers are interesting when calculating. At the same time, the arithmetic average of the projectile weight for all types of pounds for 12 gauge is 35.95 g.

2. Charging ratio.
The weight of the smokeless powder charge is determined by the formula
P = D * B
Where: P is the charge of gunpowder in the city of
D - Shot shell in g
B - Ballistic coefficient component for winter - 0.056; for summer - 0.054

A strong primer can give an increase in pressure P up to 100 kgf / cm2 (up to 9810x104 Pa) or more.
An increase in the charge of smokeless powder by 0.05 g leads to an increase in pressure P to 15-17 kgf / cm2 (up to 147.2x104 - 166.8x104 Pa)
With an increase in the mass of the projectile by 1 g, it leads to an increase in pressure P to 5.5-15 kgf/cm2.

- Smoke powder burns at a temperature of 2200-2300 degrees Celsius, smokeless - 2400 degrees.
- When burning 1 kg of smoke powder, 300 liters of gaseous products are formed, 1 kg of smokeless - 900 liters.
- heating the gas for every 273 degrees Celsius increases its volume and elasticity by 100%
- With an increase in the length of the barrel for every 100 mm, the increase in the initial velocity of the projectile is on average 7-8 m / s, the same increase in speed is achieved by adding 0.05 g of smokeless powder.
- Powder gases act on the projectile after leaving the barrel at a distance of 25 calibers from the muzzle, and give an increase in muzzle velocity by an average of 2.5%
- With an increase in the mass of the projectile by 1 g, the initial velocity decreases by 3.3 m / s.

For shooting rifled weapons: Rifle combat is checked with 3, 4, 5 or 10 rounds. After a predetermined number of shots, the middle point of impact and its deviation from the aiming point vertically and horizontally are determined. Then determine the diameter of the circle containing all the bullet holes or one less if it gave a clear separation to the side. Deviation values middle point hits of bullets vertically and horizontally from the aiming point will show how much you need to move the front sight or rear sight in height or in the lateral direction.

In addition to the magnitude of the deviations of the midpoint of impact from the aiming point, you also need to know the length of the sighting line of a given gun and the firing distance.

The value x of the front sight or rear sight movement is determined by the formula:
X \u003d (Pl * Ov [or Og]) / D
Where: D - firing distance, mm
Pl - aiming line length, mm
Ov (or Og) - deviations of the midpoint of impact from the aiming point, respectively, vertically Ov and horizontally Og

Let us assume that the length of the sighting line Pl is 500 mm, the firing distance is 50,000 mm (50 m) and the deviation of the midpoint of hits in height above the aiming point is 120 mm. Then the value of the front sight correction:
X \u003d 500 * 120 / 50,000 \u003d 1.2 mm.

More about ballistics

When firing in airless space, the maximum horizontal range of the projectile corresponds to an angle of throw of 45 degrees. The angle of throw corresponding to the maximum range of the projectile is commonly called the angle of maximum range in ballistics.
In reality, the angle of greatest range is never 45°, and, depending on the mass and shape of the projectile, varies from 28 to 43 degrees. For modern rifled weapons, the maximum range angle is 35 degrees, for shotguns - 30-32 degrees.

The maximum flight range of a shot is approximately equal to the number of hundreds of meters, which is the number of whole millimeters of the diameter of an individual shot, lined with a maximum initial speed of 375-400 m / s.

With an increase in temperature, the gun "raises", with a decrease it "lowers". The normal temperature is 15 degrees C.
With a tailwind, the projectile flies further and hits higher, and with a headwind it lies closer and lower.

With a decrease in barometric pressure, the projectile flies further and hits higher, and vice versa with an increase.

With an increase (or decrease) in temperature for every 10 degrees. starting speed shot projectile increases (or decreases) by 7 m/s.

An imaginary line described in space by the center of gravity of a moving projectile is called trajectory(Fig. 34). It is formed under the action of the following forces: inertia, gravity, air resistance and the force arising from rarefaction of air behind the projectile.

When several forces act simultaneously on the projectile, each of them informs it of a certain movement, and the position of the projectile after a certain period of time is determined by the rule of adding movements that have a different direction. To understand how the trajectory of a projectile in space is formed, it is necessary to consider each of the forces acting on the projectile separately.

In ballistics, it is customary to consider the trajectory above (or below) the horizon of the weapon. By the horizon of arms is an imaginary infinite horizontal plane extending in all directions and passing through the departure point. Departure point called the center of the muzzle of the barrel. The trace from the passing horizontal plane in fig. 34 is shown as a horizontal line.

where g is the acceleration of free fall (9.81 m / s 2).

If we assume that no forces act on the projectile after it leaves the bore, then the projectile, moving by inertia, will fly in space infinitely, rectilinearly in the direction of the bore axis and uniformly. If, after leaving the bore, only one force of gravity acts on it, then in this case it will begin to fall strictly vertically downward towards the center of the Earth, obeying the laws of free fall of bodies. Then, according to the above formula, the height of the fall H after certain periods of time (see the formula above).

2017-08-08 17:30:02

In response, about calibers in the rubble of the Internet, I found an article that, in my opinion, explains the issue of calibers well.
As they say, the new is the well-forgotten old.
The photo is just for color.

For the fifth century, one of the parameters characterizing the power of firearms has been the caliber. What is the caliber, any person who is more or less versed in the military sphere can answer - this is the size of the ammunition and the diameter of the barrel. The French origin of the term, literally meaning "how many pounds" can tell interesting story parametrization in weapons business. There is also an opinion that the basis of the word is Arabic: “galib” means ‘‘form’’. The barrel diameter of modern small arms can be characterized according to four classification systems. For example, the Saiga smoothbore hunting carbine is the 36th caliber, caliber 410, caliber 41 or 10.25 mm.

English system
Two centuries ago, both artillery systems and small arms used round ammunition. Cannonballs and mortars were made of cast iron, and in some cases were hewn out of stone. Bullets for rifles and pistols were cast from lead. England, being an advanced industrial power, distributed not only advanced technologies in metal processing, latest systems weapons, but also the original system of weights and measures. The British principle of measuring the inner diameter of the barrel was distributed in all the armies of the world. The standard was the English pound (453.59 g) of lead (for guns) or cast iron (for guns) and ammunition made from it. So, the core weighing three pounds of cast iron served as ammunition for the corresponding weapon - a three-pound cannon (according to modern classification - 76 mm). And the number of bullets made from one pound of lead, placed in the bore of a gun, explains what the caliber of small arms is. For a larger diameter barrel, respectively, a smaller amount of ammunition was obtained. The smaller the marking number, the larger the barrel diameter. The fourth caliber is much larger than the thirty-sixth. Today, this measurement system is used only for smooth-bore hunting weapons. Some foreign ammunition is supplied with the inscription Gauge, standing next to the number - an indicator of the caliber. Geyzhd is a measured lead ball, which a couple of centuries ago was used to determine the caliber of weapons.

and the West is measured in inches
After 1917, Russia switched to the metric system, and in the countries of the British Commonwealth and in the United States, trunk diameter is still measured in fractions of an inch. In Russia, the parameters are calculated in millimeters: the caliber of the AK-47 assault rifle is 7.62 mm. In the New World, this weapon is called an AK-47 of the thirtieth caliber, that is, thirty hundredths of an inch. Moreover, in the UK and the USA, different designation principles are used. Zero in the English-speaking world is omitted, the separator of tenths and hundredths in decimal fraction is not a comma, but a period. In England, about the diameter of the legendary AK bore, they will write ''caliber 300'', and in the USA ''caliber 30'' - in thousandths and hundredths of an inch, respectively. In colloquial speech, the same picture: the machine gun we are used to will be called an automatic carbine of a three-hundredth or thirtieth caliber.

what is the caliber of rifled weapons
There are two systems used by gunsmiths to measure bore diameter. In Russia, the states of the former USSR, as well as in the armies of our former satellites in Asia and Africa, the caliber is determined by the distance between opposite rifling (the smallest distance). In the countries of the North Atlantic alliance, the caliber is the distance between the bottom of the rifling (largest diameter). Thus, the most common type of small arms in the West, the M 16 rifle, has a caliber of 5.6 mm according to NATO standards, and 5.42 mm according to domestic standards. Caliber is a parameter that determines the type of gun and small arms. Barrel length is measured in calibers. If 130/55 is written in the characteristics of the gun, then this means that the caliber of the gun is 130 mm, the barrel length of 55 calibers is 7150 mm. If the barrel length is less than 30 calibers, then the gun is a howitzer, more is a cannon. In small arms, the same principle. Rifles have a barrel length of 70 calibers, carbines - 50. The domestic AKM assault rifle has a cartridge caliber of 7.62 mm, a barrel length of 54 calibers. Therefore, this type of weapon is a carbine with the ability to conduct automatic fire. The AK-74 assault rifle with a 5.45 caliber cartridge has a barrel length of 76 calibers. In accordance with the generally accepted classification, this is an automatic rifle. And the term "automatic" was introduced into circulation for ideological reasons.

Big machine gun or small gun?
The countless variety of small arms for military and civilian purposes is conditionally divided into three groups according to the size of the bore:
small caliber - less than 6.5 mm - sports and special weapons, as a rule, rimfire cartridges;
normal caliber - from 6.5 mm to 9 mm - the most common type of small arms;
large caliber - from 9 mm to 30 mm - machine guns for weapons technical means and special weapons.
Small arms, as a rule, have a barrel diameter of up to 30 mm. Small-caliber artillery begins with 30 mm. Ammunition for small arms is cartridges, for artillery shells. There may be exceptions to this classification. So aviation armament with a caliber of 23 mm is called a cannon, and shells are made for a heavy American sniper 20 mm rifle. In the special literature, products with a caliber of 30 mm are classified as small arms. Devices that absorb recoil after a shot, characteristic of artillery systems, this type of automatic weapon does not have.

The main caliber of hunters
This term, of course, does not apply to the field of small arms. The main caliber are the largest guns that formed the basis of the power of artillery warships. The larger the caliber of the guns, the more powerful the ship was. With small arms, the situation is slightly different: a large caliber is not always convenient. Only a specialist can understand the variety of modern guns and classification systems. The archaic English system of measures is still used in marking the parameters of smoothbore samples. What is a caliber for a big game hunter? This is a matter of life and death. You can compare the caliber of smoothbore hunting rifles with the metric measurement system in the following table.

Caliber value Caliber in mm
4 23,7
8 21,8
10 19,7
12 18,5
16 16,8
20 15,7
24 14,7
28 13,8
32 12,7
36 10,2

Civilian models of small arms around the world are produced in the range from 4th to 36th. In Russia, the most common hunting calibers are twelfth, sixteenth and twentieth. It should also be borne in mind that each weapon manufacturer has its own barrel manufacturing specifics. Even for such serious arms concerns as Izhmash and TOZ, the 12 gauge bore has a difference of almost a millimeter.

twelfth gauge
12 gauge guns are the most popular with hunters these days, although they weren't very common in earlier years. This is very powerful weapon. The target can be hit at a distance of up to 35 meters. Due to its versatility, it is used in fishing for any kind of game - from squirrels to elk and bear. A shot from a gun with eight-millimeter buckshot is equivalent to nine shots from a .32 pistol.

Renaissance smoothbore

Renaissance smoothbore
In the seventies of the last century, smoothbore guns began to return to military service, first as a weapon of self-defense, and then as equipment for combat units. Many weapons experts believe that the most effective melee weapon (up to 50 m) is a tactical rifle that provides a density of fire no less than an automatic weapon. Shotgun ammunition has a significant stopping power. The most common among police shotguns is 12 gauge.
In some countries, smoothbore guns are classified as assault weapons and are in service not only with law enforcement forces, but also special units. Shotguns of this caliber are equipped with US Marines guarding embassies abroad. The 12-gauge shotgun is versatile and allows the use of various types of ammunition: from rubber bullets to special devices that throw ‘‘cats’’ onto the roofs of houses. Samples with the possibility of automatic fire have been created. The most successful example is the Protecta twelve-shot assault carbine made in South Africa.

sixteen gauge
Lighter recoil - 16 gauge. This type of gun is Soviet time received the greatest distribution due to the mass production of Tula gunsmiths. Nowadays domestic producers, focusing on the foreign market, guns of this caliber are practically not produced. Hunting rifles are produced in Italy and France. The weapon is lighter than the twelfth, but more powerful and cheaper than the twentieth. Very often, samples of weapons of this caliber have a pump-action design without a butt. 16 gauge is popular with security personnel, although some hunters call it "dying".

choice of professionals
20 gauge is mainly used by professional fishermen. It has less lethal force than the first two options. The weight of the ammunition is 10-12 grams less than that of the 12 gauge. The main advantage is the lower weight, which is not the least important for long walks. 20 caliber received a second life with the advent of new magnum cartridges with shot weights up to 36 grams. Owners note a significantly lower recoil force with the same weight of ammunition and the comfort of using such weapons.