12.5 caliber weapon. Smoothbore calibers

In response to the question of 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 now, one of the parameters characterizing power firearms, is the caliber. Any person more or less knowledgeable in the military sphere can answer what a caliber is - it is the size of the ammunition and the diameter of the barrel. The French origin of the term, literally meaning ''how many pounds'', may reveal interesting story parameterizations in weaponry. There is also an opinion that the basis of the word is Arabic: “Ghalib” means “form”. Modern trunk diameter small arms can be characterized according to four classification systems. For example, the Saiga smoothbore hunting carbine is 36 caliber, 410 caliber, 41 caliber 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 hewn out of stone. Bullets for rifles and pistols were cast from lead. England, being an advanced industrial power, distributed not only Hi-tech in metal processing, latest systems weapons, but also an original system of weights and measures. The British principle of measuring the internal diameter of a barrel was widespread in all armies of the world. The standard was the English pound (453.59 g) of lead (for guns) or cast iron (for cannons) and ammunition made from it. Thus, a cannonball 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 a small arms is. For a barrel with a larger diameter, correspondingly, less ammunition was obtained. The lower the number of markings, the larger the diameter of the barrel. The fourth caliber is significantly larger than the thirty-six. Nowadays, this measurement system is used only for smoothbore hunting weapons. Some foreign ammunition is equipped with the inscription Gauge next to the number - the caliber indicator. A gage is a measuring lead ball that was used to determine the caliber of a weapon a couple of centuries ago.

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

what is a caliber rifled weapons
Arms companies use two systems for measuring 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 grooves (shortest distance). In the countries of the North Atlantic Alliance, 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 the characteristics of a gun say 130/55, this means that the caliber of the gun is 130 mm, the barrel length of 55 caliber is 7150 mm. If the barrel length is less than 30 calibers, then the gun is a howitzer; if it is longer, it is a cannon. The same principle applies to small arms. Rifles have a barrel length of 70 calibers, carbines - 50. The domestic AKM assault rifle has a cartridge caliber of 7.62 mm, barrel length - 54 calibers. Consequently, this type of weapon is a carbine with the ability to fire automatically. 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 “machine gun” was introduced into circulation for ideological reasons.

Big machine gun or small cannon?
The countless variety of small arms for military and civilian purposes according to the size of the bore is conventionally divided into three groups:
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 arming technical equipment and special weapons.
Small arms, as a rule, have a barrel diameter of up to 30 mm. Small-caliber artillery begins at 30 mm. Ammunition for small arms is cartridges, for artillery - shells. There may be exceptions to this classification. Thus, aircraft weapons with a caliber of 23 mm are called cannons, and shells are made for the heavy American 20 mm sniper rifle. In the specialized literature, products with a caliber of 30 mm are classified as small arms. This type of automatic weapon does not have devices that absorb recoil after a shot, characteristic of artillery systems.

Main caliber of hunters
This term, of course, does not apply to the field of small arms. The main caliber is the guns largest size, which 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 a little 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 smooth-bore samples. What is a caliber for a big game hunter? It's 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 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 specific barrel manufacturing. Even among such serious arms concerns as Izhmash and TOZ, the 12 gauge bore has a difference of almost a millimeter.

Twelve gauge
12 gauge guns are the most popular among hunters these days, although in previous years they were not very common. This is a very powerful weapon. The target can be hit at a distance of up to 35 meters. Due to its versatility, it is used when fishing for any type of game - from squirrel to elk and bear. Firing eight millimeter buckshot from a shotgun is equivalent to nine shots from a .32 caliber pistol.

Renaissance smoothbore

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

Sixteen gauge
Lighter in recoil - 16 gauge. This type of guns Soviet time became most widespread due to the mass production of Tula gunsmiths. These days, domestic manufacturers, focusing on the foreign market, practically do not produce guns of this caliber. 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, weapons of this caliber are pump-action without a stock. 16 gauge is popular with security personnel, although some hunters call it “dying.”

choice of professionals
20 gauge is primarily used by professional fishermen. It has less destructive power than the first two options. The weight of the ammunition is 10-12 grams less than that of 12 gauge. The main advantage is lower weight, which is of great importance during long walks. 20 gauge received a second life with the advent of new Magnum cartridges with shot weights up to 36 grams. Owners note significantly lower recoil force with the same weight of ammunition and the comfort of using such weapons.

IN different countries world, the caliber of a weapon is both designated and measured in different ways: either by the margins or by the bottom of the rifling of the barrel. In addition, the designation of the cartridge caliber can be conditional, for example, small-caliber cartridges. 222Remington and .22LR have almost the same caliber, but differ in type (the first cartridge is central ignition (capsule), the second is rimfire) and the size of the cartridge case.

So, in the countries of the former USSR, the caliber of rifled weapons is based on the distance between the opposite fields of the rifling, in NATO countries - by the distance between the bottom of the opposite rifling, the caliber of bullets (shells) is the largest diameter.

The caliber of rifled small arms in countries that use the English system of measures (USA, UK, etc.) is measured in fractions of an inch: in the USA - in hundredths (0.01 inches), in the UK - in thousandths (0.001 inches). In general, calibers are converted on the basis that 1 inch (1") is equal to 25.4 mm (2.54 cm).

In the inch system, calibers are designated in hundredths or thousandths of an inch, but without a leading zero, i.e. .50 caliber means 0.5 inches or 12.7mm, and .30 means 0.3 inches or 7.62mm.

In the entry, the zero of the integer part of the number and the designation of the unit of measurement (inch) are omitted, while in English speaking countries ah, a dot is used as a decimal separator: .45, .450 In Russian-language texts, traditional English and American calibers are written in exactly the same way, that is, with a dot, and not a comma, the decimal separator accepted in Russia: caliber 45 caliber 450, etc. d; colloquially: forty-five caliber, four hundred and fifty caliber.

In countries using the metric system ( Russian Federation and all countries of the world except the USA, Great Britain, Myanmar and Liberia), the caliber is measured in millimeters, in its designation the length of the sleeve is added through the multiplication sign, for example 7.62 × 54 mm. It should be taken into account that the length of the cartridge case is not a characteristic of the caliber, but a characteristic of the cartridge. The cartridges can be the same caliber, but different lengths.

The following classification of small arms calibers is generally accepted:

Correspondence table for the most common calibers of rifled small arms

Shotgun caliber

For smoothbore guns, calibers are measured in a fundamentally different way: the number indicating the caliber is the number of round bullets for a particular gun that can be cast from 1 English pound of lead (453.5 g).

In this case, the bullets must be spherical, identical in mass and diameter, which is equal to the internal diameter of the barrel in its middle part.

The smaller the trunk diameter, the large quantity bullets are made from a pound of lead. Thus, the tenth gauge is larger than the twentieth, and the sixteenth is smaller than the eighth.

There are the following calibers of hunting rifles measured by the number of round caliber (150 mm from the breech) bullets made from one English pound (453.6 g) of pure lead: 2, 4, 8, 10, 12, 16, 20, 24, 28, 32 .
Calibers of hunting rifles produced today in Russia (and the USA): 12, 16, 20, 24, 28, 410; (10, 12, 16, 20, 24, 28, 410).

Barrel bore diameters of the most popular hunting calibers from different countries:

PMK - Permanent International Commission of the Brussels Convention for the Testing of Hand Firearms.

Sources:

Caliber is the diameter of the bore, expressed in different measures. The calibers of smoothbore guns from 4 to 32 are still, following tradition, designated by the number of round caliber (equal to the caliber of the barrel) bullets cast from one English trade pound of lead, equal to 453.6 g. It is trade for in the Anglo-Saxon system There is also another pound - pharmaceutical pound (373.2 g). If a pound of lead produces 12 caliber ball bullets, then the gun will be 12 gauge, if it is 20-20 gauge, etc. The larger the number indicating the caliber, the smaller the bore diameter (caliber).

Since the walls of a metal sleeve are thinner than those of a paper (plastic) sleeve, the bores of barrels made for a metal sleeve have a larger diameter than the bores of barrels made for a paper (plastic) sleeve. Nowadays, almost all guns are produced with a paper (plastic) cartridge case.

The caliber of large-caliber fittings for black powder was designated in the same way as smooth-bore guns: there were fittings of 12, 16, 29 and other calibers. Calibers for rifled weapons were also indicated in lines, but are now indicated either in mm (5.6; 7.62; 11.43) or in fractions of an inch.

First of all, you should remember the following data: 1 inch = 10 lines = 100 dots; 1 inch = 25.4 mm; 1 line = 2.54 mm; 1 point = 0.254 mm; 1/10th of a point = 0.0254 mm. Based on this, we can easily understand any caliber designation system and translate caliber designations from one system to another. For example, S.I. Mosin’s three-line rifle has a caliber of 3×2.54 = 7.62 mm. Since in the USA calibers are expressed in hundredths of an inch (in other words, in points), then caliber 30 must be multiplied by 0.254, and the English caliber 300 by 0.0254, because in the UK calibers are indicated not in hundredths, but in thousandths of an inch ( i.e. in tenths of a point). In this case, we get: 30 × 0.254 = 7.62 mm; 300×0.0254 = 7.62 mm.

As you can see, caliber 3 lines, caliber 30, caliber 300 caliber 7.62 mm are equal to each other, but expressed differently. In the same way, it is easy to verify that calibers 2.2; 22; 220 is equal to 5.6 mm, i.e. the caliber of small-caliber weapons widespread throughout the world.

In rifled weapons, the diameter of the bore is measured either by the rifling or by the margins. Therefore, the same caliber can be designated differently, which sometimes leads to confusion. Thus, the caliber of a 5.6 mm rifle is sometimes designated as 5.45 mm. In the first case, the caliber is measured by rifling, in the second - by margin.

We produce smoothbore weapons in five calibers - 12, 16, 20, 28 and 32. According to the standards, 10-gauge is also provided, but such guns are not produced. We have no longer made 8-caliber guns for a long time, and at the end of the 1940s, the 24-caliber was excluded from the standards and soon the production of guns of this caliber ceased. IN international system shotgun calibers, this caliber remains.

In Russia they make guns with barrels following sizes: 12 gauge - 18.2–18.7 mm; 16th - 17–17.25 mm; 20th - 15.7–15.95 mm; 28th - 14–14.25 mm; 32nd - 12.5–12.75 mm.

Gun barrels of calibers from 12 to 28 inclusive are made for a paper sleeve, and 32 for a metal sleeve.
The Tula Arms Plant produces 12-gauge weapons with bore diameters of 18.5–18.7 mm, and the Mechanical Plant in Izhevsk produces 18.2–18.25 mm. We advise you to remember this circumstance: when equipping cartridges at home, this is very important to take into account.

Sources:

It is customary to denote the caliber of large-caliber shotguns and rifles by the number of round bullets from a pound of pure lead: 12 gauge - that means 12 bullets can be made from 0.410 kg (1 pound) of lead for such a barrel, 24 means 24 bullets, etc.; This means that the larger the number, the smaller the diameter.

But the pounds are different in different countries, and they did not always drill accurately, then they began to make cartridges from different materials, with different wall thicknesses, and the barrels were drilled along the internal channel of the sleeve. It is clear that with the same outer dimensions of the sleeve, its internal channel is wide if the walls are made of thin sheet brass, and much narrower if the walls are made of thick folder. The name in both cases remains the same according to custom, although this does not at all correspond to the real diameter of the trunk and still misleads many insufficiently knowledgeable hunters.

Even in barrels for the same 12-cal folder cartridges. There are huge differences, reaching up to ¾ mm, and are greatly reflected in the selection of supplies, especially wads. And it is clear that a bullet too loose for an 18.8 mm barrel will be able to inflate or rupture an 18.2 mm barrel.

But these are all measurements of barrels for a 12 caliber paper sleeve. Barrels for thick brass are drilled at 19.35–19.20 mm, and for thin brass at 19.60 mm; it is clear that in reality this is a different caliber, suitable for 10 cal. under the folder sleeve, here the charge and wads should be different.

It is very easy to find out for which sleeve the barrel is drilled by the stamps, since the stamps are placed according to the actual caliber and by measuring it: a wad is driven from the treasury approximately a quarter (17–18 cm) into a clean, slightly lubricated barrel and “wax” is poured , paraffin, etc., and best of all sulfur cuttings; When the casting hardens, it is pushed out of the barrel. If the barrel (as in the vast majority of cases happens) is made for a folder sleeve, then the muzzle end of the casting will fit into the folder sleeve with a slight gap, and into the brass case with a very large gap. If the barrel is made for a brass sleeve, then the end of the casting will not fit into a folder.

Sources:

• — Moscow: Publication of the All-Khotsoyuz. - 1929.

They have their own diversity among the general mass, which can impress any connoisseur of small arms.

If we turn to the caliber of a rifled hunting weapon, then there is a completely different system for determining the caliber itself than that of a smoothbore gun.

In addition, from the name itself it is clear that the barrel has rifling, thanks to which the bullet begins to rotate and receives a high starting speed.

The speed and range of a projectile from smoothbore weapons will be less than that of a rifled weapon, but at short distances, in terms of destructive power, this type of weapon is considered a very serious threat.

All novice hunters first think about what kind of caliber of smoothbore hunting weapon choose, because there is so much to choose from.

There is no doubt that someone becomes the owner of one or another weapon by inheritance. There is no longer a choice of caliber, although nothing prevents you from selling the weapon and buying another one.

Now we will try to understand all the existing calibers and the system for their determination, as well as the history of their origin.

What calibers of smoothbore hunting weapons exist?

Contents of the article:

In the distant twentieth century, the army began to actively use smooth-bore weapons. Long time England was a leader in the production of weapons and ammunition, so it was she who defined the system by which one caliber is distinguished from another.

This system is not complicated at all. Take lead weighing 453.59 g, which is equal to one pound. Next, spherical bullets are poured from it, but so that they are all the same weight and diameter.

After this, all received bullets are counted. If there are 10 bullets, then the caliber is 10. When the number of bullets is different, then the caliber is correspondingly different.

The diameter of the bullet itself must correspond to the diameter of the barrel in its middle, that is, in the bore itself. From this the conclusion emerges that for a gun with a smaller barrel diameter there will be more bullets, therefore the caliber in digital format will be larger, but in reality it is smaller.

For example, a 20 gauge will be smaller than a 16 gauge, despite being numerically superior. Now let's look at the main calibers not only for hunting, but also for self-defense purposes.

Caliber 12

It is difficult to name a hunter who has never shot from a 12 gauge, because this caliber is in the leading position. Its popularity among hunters knows no bounds.

Almost any weapon brand has in its model range 12 gauge shotguns. This is not just for the sake of it, because this caliber has a number of practical advantages and advantages over other calibers.

It allows its owner to change the powder charge over a wide range. In addition, it can use a wide variety of bullets, which are not difficult to obtain.

Any shot or buckshot can be used in this caliber. Thus, 12 gauge allows you to hunt all types of animals and birds without fear and with great efficiency.

If we note some specific models of guns with this caliber, I would like to focus on TOZ-34, MP-27, MP-155, MP-153 and MP-18.

Caliber 16

A decent half of Soviet hunters had 16-gauge shotguns in their arsenal, since they did not give as much recoil as 12-gauge ones, and also had less weight, which was a significant advantage for hunting.

If you read the article carefully, you understand that this caliber produces 16 identical bullets from a pound of lead.

Hunting weapon This caliber allows you to hunt small and large game, so it also has a certain popularity among hunters.

Ease of use, good shooting sharpness, high power, practicality and low weight attracted the attention of hunters, who called 16-gauge shotguns the golden mean among the entire arsenal.

Caliber 20

Shotguns with this caliber are quite small, so they are even called women's guns. The powder and shot charge of this caliber is very small, so now almost no one uses it.

There is no doubt that there were times when hunters actively hunted with guns of this caliber, since they were very light and weighed about 2.7 kg.

You need to be able to shoot very accurately to hit the target with a 20 gauge. The IZH-58 shotgun model can be called a prominent representative of this caliber.

If we talk about more modern models of shotguns, then we should note the MP-24 and MP-43, which are now little used.

Caliber 24 and 28

Shotguns with such calibers are almost never used by our hunters. The reason for this is the same as with the 20 gauge.

At first glance, a gun of this caliber is light and practical, the recoil is small, the accuracy is high, but it is difficult to hit. Here you need to learn to shoot for a long time in order to successfully use such a weapon on a hunt.

Once the hunter has mastered his marksmanship skills, even with this caliber he can go duck or hare hunting with great pleasure.

We can also say about calibers 32 and 36, which are very rare, but are on the market and attract the attention of gun lovers.

Caliber of smoothbore hunting rifles.

Caliber of smoothbore hunting rifles according to old tradition measured by the number of round bullets that can be made from one English pound (453.6 g) of pure lead (4, 8, 10, 12, 16, 20, 24, 28, 32).
In Russia, hunting rifles are produced in calibers 12, 16, 20, in the USA - 10, 12, 16, 20, 24, 28.
The most common calibers of smoothbore weapons are 4, 8, 12, 16, 20, 28, 32.

Caliber of rifled weapons

Calibers of rifled weapons are measured in whole, tenths and hundredths of a millimeter, for example 7.62 mm.

At the beginning of the 20th century in Russia, the caliber of rifled firearms was measured in fractions of an inch or “lines” (1 inch = 25.4 mm = 10 lines = 100 points).
This is where the name “three-line” of the I. S. Mosin rifle of the 1881 model came from - 3 lines or 7.62 mm.

In a number of English-speaking countries, the calibers of rifled long-barreled and short-barreled weapons are measured in hundredths and thousandths of an inch and are designated: caliber 30 (USA), caliber 300 (England), which when converted to the metric system in both cases means a caliber of 7.62 mm.

The spaces between the cuts are called margins.

Therefore, the caliber of a rifled weapon (barrel bore diameter) can be measured as the distance either between two opposite fields in diameter (7.62 mm; 5.45 mm) or between rifling (7.92 mm; 5.6 mm).

So, if we compare the 9x18 mm PM cartridge and the 9x17 mm Browning (the second number indicates the length of the cartridge case), then, despite the same caliber, their bullet diameters are different.

The bullet diameter of the first cartridge is 9.2 mm, and the second - 9.0 mm.
Accordingly, the barrel diameters for these cartridges are 9.0 mm for the first, and 8.8 mm for the second.

Diameter of a bullet for a rifled weapon.

The diameter of a bullet for a rifled weapon corresponds to the diameter of the bore measured by the rifling (i.e., the larger diameter). In this case, the bullet has the ability to crash into the rifling and acquire a rotational movement.
In this case, breakthrough of powder gases between the walls of the barrel and the bullet is not allowed.

In some cases, caliber designations, in addition to determining the diameter of the bullet (or barrel), can provide information about the length of the cartridge and its power.
So, among the designations of 9-mm cartridges there are such as .357, .38, .380.
These cartridges have a caliber of 9 mm, but differ in power or other parameters.