Caliber length. Weapon calibers. Artillery and small arms
Characterized by input and output gauges.
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The caliber is indicated on both the weapon and the ammunition. However, with the same caliber numbers, the diameters of the bores (and bullets) may differ. For example, 9x18 Makarov and 9x19 Parabellum (or 9x17 Browning) cartridges have the same caliber 9 mm. For a Makarov pistol, the distance between the fields (the smallest bore diameter) is 9 mm, the distance between the rifling is 9.25 mm, and the bullet diameter is 9.27 mm. For weapons for the second ammunition, the distance between fields is 8.8 mm, the distance between rifling is 9 mm, and the bullet diameter is 9.03 mm.
The caliber of rifled small arms in countries that use the English system of measurements 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 entry, the zero of the integer part of the number and the designation of the unit of measurement (inch) are omitted, and 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 rather than a comma, the decimal separator used in Russia): cal.45, cal.450; in colloquial speech: forty-five caliber, four hundred and fifty caliber.
Classification of small arms calibers:
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, one of the differences between bullets and shells is 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. When fired, the projectile is given rotation with the help of driving belts (made from materials of less hardness than the shell of the projectile body) [ ] .
The most common calibers of pistols, rifles and machine guns:
- .577 (14.7 mm) - the largest of the serial ones, the Eley revolver (Great Britain);
- .50 (12.7 mm) - used for heavy machine guns and sniper rifles;
- .45 (11.43 mm) - the “national” caliber of the USA, the most common in the Wild West; in 1911, the Colt M1911 self-loading pistol of this caliber entered service with the Army and Navy and, with minor changes in 1926, served until 1985, when the US armed forces switched to 9 mm for the Beretta 92; continues to be used in civil circulation;
- .40 (10.2 mm) is a relatively new pistol caliber; provides better efficiency, for which it has gained great popularity in US law enforcement agencies;
- .38; .357 (9 mm), 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 Nagan system revolver, TT pistol, Mosin rifle, Simonov self-loading carbine, Kalashnikov assault rifle, Kalashnikov light machine gun, Dragunov sniper rifle, PK machine guns /PKM/PKT ;
- .22 LR (5.6 mm) - caliber of ammunition for the TOZ-8 rifle (TOZ-10, TOZ-12);
- .223 (5.56 mm) - caliber of ammunition for the M16 automatic rifle;
- 5.45 mm - AK-74 ammunition caliber;
- 2.7 mm is the smallest serial caliber; used in the Hummingbird pistol of the Franz Pfannl system (Austria) [ ] .
Caliber of smoothbore or other hunting weapons
For shotguns, calibers are measured differently: the caliber number refers to the whole number of spherical bullets that can be cast from 1 English pound of lead (453.59 g). 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 bore, the more bullets can be produced from a pound of lead. Thus, the twentieth gauge is less than the tenth, and the sixteenth is less than the twelfth.
You can also use the formula for determining caliber (K) by barrel diameter (D, cm):
K = 453, 59 ⋅ 6 π ⋅ D 3 ⋅ 11, 3415 ≈ 76, 3842 D 3 (\displaystyle K=(\frac (453.59\cdot 6)(\pi \cdot ((D)^(3) )\cdot 11.3415))\approx (\frac (76.3842)((D)^(3))))
In the designation of the caliber of cartridges for smooth-bore weapons, as in the designation of cartridges for rifled weapons, it is customary to indicate the length of the cartridge case, for example: 12/70 - 12 gauge cartridge with a 70 mm long sleeve. The most common case lengths: 65, 70, 76 mm (Magnum); Along with them there are 60 and 89 mm (Super Magnum).
The most common hunting rifles in Russia are 12 gauge. There are (in descending order of prevalence) 20, 16, 24, 28, 36, .410, and the distribution of .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 the drilling for a certain type of cartridge case: metal, plastic or folder. For example, a 12-gauge barrel drilled for a folder or plastic sleeve has a bore diameter of 18.3 mm, while drilled for a metal sleeve - 19.4 mm. In addition, we should not forget that the barrel of a shotgun weapon usually has various types of choke constrictions, through which not any bullet of its caliber can pass through without damaging 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 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 is the diameter of the bore, expressed in different measures (see table)
No. Heat engines Name Caliber designation based on the number of balls per pound Conventional bullet caliber in thousandths of an inch Barrel caliber in millimeters
range (from - to)
1 Large-caliber Signal 4 0,935 (23,35 - 26,72) 2 gregarious 8 0,835 (20,80 - 21,21) 3 Duck 10 0,775 (19,00 - 20,25) 4 Official 12 0,729 (18,20 - 18,93) 5 Medium caliber Intermediate 14 0,693 (17,20 – 17,60) 6 Hunting 16 0,662 (16,80 – 17,40) 7 Commercial 20 0,615 (15,50 - 16,31) 8 Canine 24 0,579 (14,7 - 15,20) 9 Normal caliber Fur 28 0,550 (13,40 - 14,35) 10 Teenage 32 0,502 (12,37 - 13,36) 11 36 (411 TKM) 70 0,410 (10,00 -11,10) 12 Legislative 366 TCM 92 0,374 (9,48 – 9,62) 13 Small-caliber Avian 106 0,350 (8,70 – 9,25) 14 Sniper 174 0,300 (7,60 – 7,85) 15 Sports 300 0,250 (6.10 – 6,38) 16 Elementary 460 0,220 (5,42 - 5,56) 17 For shooting range 840 0,177 (4,45 - 4,53) *All errors in determining the caliber value are explained by the different weight of a pound of lead in different number systems, as well as rounding rules and the desire to get a beautiful number in a series.
Russian artillery caliber
In Europe the term artillery caliber appeared in 1546, when Georg Hartmann from Nuremberg developed a device called the Hartmann scale. It was a prismatic tetrahedral ruler. Units of measurement (inches) were marked on one face, and the actual dimensions (based on weight in pounds) of iron, lead and stone cores, respectively, were marked on the other three.
Examples (approximately):
- 1 face - the mark of a lead core weighing 1 pound - corresponds to 1.5 inches;
- 2nd face - mark of an iron core weighing 1 pound - corresponds to 2.5 inches;
- The 3rd face - the mark of a stone core weighing 1 pound - corresponds to 3 inches.
Thus, knowing the size or weight of the projectile, it was possible to easily assemble, and most importantly, manufacture ammunition. A similar system existed in the world for about three hundred years.
In Russia before Peter I there were no uniform standards. The cannons and squeaks available in the army were each characterized separately by the weight of the projectile, in Russian national units. Pre-Petrine inventories mention guns ranging from 1/8 hryvnia to a pood. At the beginning of the 18th century, on the instructions of Peter I, Feldmaster General Count Bruce developed a domestic caliber system based on the Hartmann scale. It divided the guns according to the artillery weight of the projectile (cast iron core). The unit of measurement was the artillery pound - a cast iron ball with a diameter of 2 inches and a weight of 115 spools (about 490 grams). It did not matter what types of projectiles the gun fired - buckshot, bombs or anything else. Only the theoretical artillery weight that a gun could fire given its size was taken into account. Tables were also developed correlating artillery weight (caliber) with bore diameter. Artillery officers were required to operate with both calibers and diameters. In the “Naval Charter” (St. Petersburg, 1720), in chapter seven “About the artillery officer, or konstapel”, in paragraph 2 it is written: “You must measure the cannonballs to see if their diameters are similar to the calibers of the guns and place them on the ship according to your places." This system was introduced by royal decree in the city and lasted for more than a century and a half.
- 3-pounder gun, 3-pounder gun - official names;
- artillery weight 3 pounds - the main characteristic of the gun;
- size 2.8 inches - bore diameter, an auxiliary characteristic of the gun.
In practice, it was a small cannon that fired cannonballs weighing about 1.5 kg and had a caliber (in our understanding) of about 71 mm.
Kozlovsky David Evstafievich in his book gives a translation of Russian artillery weight
A special weapon was intended for bombs - a bombard, or mortar. Its tactical and technical characteristics, combat missions and calibration system allow us to speak of a special type of artillery. In practice, small bombards often fired ordinary cannonballs, and then the same gun had different calibers - a general one of 12 pounds and a special one of 10 pounds.
The introduction of calibers, among other things, became a good material incentive for soldiers and officers. Thus, in the “Naval Charter”, printed in St. Petersburg in 1720, in the chapter “On rewarding” the amounts of reward payments for guns taken from the enemy are given:
- 30 pound - 300 rubles,
- 24 pound - 250 rubles,
- 18 pound - 210 rubles,
- 12 pound - 170 rubles,
- 8 pound - 130 rubles,
- 6-pound - 90 rubles,
- 4 or 3 pound - 50 rubles,
- 2 pound or less - 15 rubles.
In the second half of the 19th century, with the introduction of rifled artillery, the scale was adjusted due to changes in the characteristics of the projectile, but the principle remained the same.
1. The distance between two opposite grooves.
2. Inner diameter of the bore.
3. Distance between fields and grooves.
4. The distance between two opposing fields.
4. Purpose of the mainspring valve:
1. Serves for fastening the mainspring and handle with screw.
2. Serves to attach the mainspring, handle with screw and hold the magazine at the base of the handle.
3. Serves to attach the mainspring to the base of the handle.
5. Purpose of the handle base:
1. Serves for store premises.
2. Serves to attach the handle.
3. Serves for fastening the mainspring.
4. Serves for all of the above.
6. Purpose of the shutter delay reflector:
1. Serves to hold the cartridge case in the bolt cup.
2. Serves to increase the flight range of the cartridge case.
3. Serves to prevent reflection of the shutter surface when aiming.
4. To increase the lethal effect of the bullet.
5. Serves to eject the cartridge case out through the bolt window.
7. Purpose of the pistol frame:
1. For attaching the barrel and trigger guard.
2. For attaching the base of the handle, barrel, trigger guard and making it easier to hold the pistol in your hand.
3. The frame serves to connect all parts of the gun.
8. Purpose of the pistol barrel:
1. Serves to direct the flight of the bullet.
2. Serves to put a return spring on it.
3. Serves to place a cartridge in it.
4. Serves to impart rotational motion to the bullet.
9. Purpose of the trigger rod with the cocking lever:
1. For decocking the hammer and cocking the hammer when pressing the tail of the trigger.
2. For self-cocking shooting.
3. For all of the above.
10. Purpose of the return spring:
1. Serves to activate the hammer, cocking lever and trigger rod.
2. Serves to lock the barrel bore when firing.
3. Serves to return the bolt to the front position after firing.
11. Purpose of the mainspring:
1. To activate the trigger.
2. To operate the cocking lever.
3. To activate the trigger rod.
4. For all of the above.
12. Purpose of wiping the gun:
1. To disassemble the pistol.
2. To reassemble the pistol after disassembling.
3. To clean the gun.
4. To lubricate the gun.
5. For all of the above.
13. Shutter purpose:
1. To cock the trigger.
2. To remove the cartridge.
3. To lock the bore when firing.
4. To hold the sleeve.
5. To feed a cartridge from the magazine into the chamber.
6. For all of the above.
14. Purpose of a pistol holster:
1. For carrying and storing a pistol, spare magazine and cleaning.
2. For the convenience of carrying a pistol.
3. To practice exercises during practical shooting.
15. Purpose of the notch between the front sight and the rear sight:
1. To prevent reflection of the shutter surface when aiming.
2. For the convenience of retracting the shutter by hand.
16. Purpose of the trigger:
1. To strike the striker.
2. To strike the striker.
3. To strike the bolt.
17. Purpose of the trigger:
2. For decocking and cocking the hammer when firing by self-cocking.
3. For cocking the hammer when firing by self-cocking.
4. To press it with your index finger.
5. To connect to the front trigger rod pin.
18. Purpose of the drummer:
1. To perceive the trigger blow.
2. To break the cartridge primer.
3. To strike the striker.
19. Purpose of the pistol slide stop:
1. To hold the pistol bolt in the rearmost position.
2. To hold the bolt in the forward position after firing.
3. To hold the bolt in the rear position after all the cartridges from the magazine have been used up.
20. What are the bore fields of rifled firearms called?
1. The distance between two opposite grooves.
2. Width of rifling.
3. The distance between opposite fields.
4. Gaps between cuts.
21. Purpose of the pistol strap:
1. To ensure the pistol is attached to the waist (trouser) belt.
2. For ease of carrying the PM in a holster.
3. To prevent loss of the PM and its falling out of the holster.
22. Purpose of the notches on the sides of the shutter:
1. To prevent reflection of the shutter surface when aiming.
2. For the convenience of retracting the shutter by hand.
3. For all of the above.
23. Purpose of the wide mainspring feather:
1. To actuate the cocking lever with the trigger rod.
2. To activate the trigger.
3. To operate the trigger.
24. Purpose of the fuse:
1. To press it with your finger.
2. To perceive the trigger blow.
3. To hold the firing pin in the bolt.
4. To ensure safety when handling the gun.
25. Purpose of the trigger guard:
1. To hold the shutter in the rearmost position.
2. For attaching the trigger.
3. To protect the trigger from accidental pressing.
4. To limit the movement of the shutter to the rear extreme position.
26. Purpose of the handle with a screw:
1. For attaching the mainspring to the base of the handle.
2. To cover the base of the handle and make it easier to hold the pistol in your hand.
3. To hold the gun.
27. Purpose of the store:
1. To hold eight rounds.
2. For insertion into the base of the handle.
3. To ensure the supply of cartridges from the magazine to the chamber.
4. For all of the above.
28. Purpose of the feeder tooth:
1. To turn on the bolt delay when all the cartridges from the magazine are used up.
2. To hold the bolt in the rear position after all the cartridges from the magazine have been used up.
3. To hold the feeder in the magazine body.
29. Purpose of a sear with a spring:
1. To release the trigger from cocking.
2. To keep the trigger cocked.
3. To hold the trigger on the combat and safety cocks.
4. To keep the trigger on the safety cock.
5. For gripping the trigger ledges.
The caliber of a weapon, along with the length of the barrel, is one of the most important characteristics of a firearm; this fully applies to hunting smooth-bore weapons.
The caliber of a smoothbore hunting rifle refers to the diameter of its bore. The word caliber is of Arabic origin, derived from the word "galib", which means "shape".
Some hunters consider classic double-barreled shotguns with horizontal barrels to be the best shotguns, the most common among our hunters: IZH-54, IZH-58, .
Domestic semi-automatic machines are very popular. In recent years, foreign-made 12-gauge shotguns have become very popular and are gaining more and more popularity.
Both of these calibers are not intended for hunting, but are used for recreational shooting and self-defense purposes.
Which caliber is best for hunting?
All novice hunters, when purchasing their first gun, are interested in the question of which caliber to choose. Let us warn you right away that there is no clear answer to this question.
The choice of caliber depends on what game is intended to be hunted, in what way, and at what distance.
When choosing a caliber, hunters have strong personal preferences that outweigh any logical arguments in favor of a particular caliber. In any case, the choice should be reasonable; you should not go after a bear with a 410 caliber gun, this cannot end well.
In our opinion, the most correct caliber for a beginning hunter is 12. It is the most versatile. widely available in stores. Also, the choice of cartridges for it is the widest.
Edited 08/31/2019
Caliber - the diameter of the bore by rifling or margin; one of the main quantities that determine the power of a firearm.
The classification of small arms calibers is as follows:
- 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, 20 mm and above - artillery.
Caliber is measured
- For projectiles (bullets), the caliber is determined by their largest diameter
Guns with a conical barrel are characterized by input and output calibers.
Caliber of smoothbore weapons
For smoothbore weapons, the caliber number refers to the whole number of spherical bullets that can be cast from 1 English pound of lead (453.59 g). 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 bore, the more bullets can be produced from a pound of lead. Thus, the twentieth gauge is less than the tenth, and the sixteenth is less than the twelfth.
You can also use the formula for determining caliber (K) by barrel diameter (D, cm):
When designating the caliber of cartridges for smooth-bore weapons, it is customary to indicate the length of the cartridge case, for example: 12/70 - a 12-gauge cartridge with a sleeve length of 70 mm. The most common case lengths: 65, 70, 76 mm (Magnum); Along with them there are 60 and 89 mm (Super Magnum).The length of the chambers of hunting shotguns in millimeters is indicated below
The actual diameter of the bore of a given caliber depends, firstly, on the specific manufacturer and, secondly, on the drilling for a certain type of cartridge case: metal, plastic or folder. For example, a 12 gauge barrel, drilled for a folder or plastic sleeve, has a bore diameter of 18.3 mm, while drilled for a metal case - 19.4 mm. In addition, we should not forget that the barrel of a shotgun weapon usually has various types of choke constrictions, through which not any bullet of its caliber can pass through without damaging 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 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 of rifled weaponsCaliber of rifled weapons in fractions of inches (English system)
The caliber of rifled small arms in countries that use the English system of measures is measured in fractions of an inch: in the USA - in hundredths(0.01 inch), in the UK - in thousandths(0.001 inch).In the entry, the zero of the integer part of the number and the designation of the unit of measurement (inch) are omitted, and a dot is used as the decimal separator. For example, .45, .450. In Russian texts, traditional English and American calibers are written in the same way (with a period rather than a comma, the decimal separator adopted in Russia): cal.45, cal.450
In colloquial speech they say only fractions of an inch: forty-five caliber, four hundred and fifty caliber.
In the West, for civilian cartridges, the name of the company or cartridge standard is usually added to the caliber: .45 Colt, .41 S&W, .38 Super, .357 Magnum, .220 Russian.
Caliber of rifled weapons in the metric system
In countries that use the metric system of measures (in particular, in Russia), the caliber is measured in millimeters; in the designation, the length of the sleeve is added through the multiplication sign: 9 × 18 mm.It must be taken into account that the length of the cartridge case is not a characteristic of the caliber, but a characteristic of the cartridge. With the same caliber, cartridges can be of different lengths and have different case lengths.
In the West, such digital recording is used mainly for military cartridges.
Caliber of rifled weapons in lines
In Russia until 1917 and a number of other countries, caliber was measured in lines. One line equals 1/10 inch (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 (Mosin system) of three line caliber (i.e. 7.62 mm or, if you are wondering, .30).
There are also more complex designations, for example, several designations for the same cartridge: nine millimeters, Browning, short; three hundred eighty, auto; nine by seventeen. This 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 into civilian circulation receives a new designation
Caliber comparison table
In general, calibers are converted on the basis that 1 inch (1") is equal to 25.4 mm.
But it should be borne in mind that in different countries the caliber is measured differently (by the margins or the bottom of the rifling). In addition, the designation of the cartridge caliber can be conditional - for example, the .22LR and .222Rem cartridges actually have the same caliber, but differ radically in type (the first is rimfire, the second is central) and the size of the cartridge case. Likewise, .38 and .357 caliber cartridges have de facto the same bullet diameter, but the .357 magnum cartridge has a longer case (32 mm versus 29 mm) and a more powerful powder charge.Interesting questions sometimes arise during the writing and then discussion of materials about weapons. This happened after my article about the standards of protection for military personnel and law enforcement officers. To be honest, it was somewhat unexpected for me.
An interesting conversation arose about which was used during the tests. More precisely, about the calibers of these weapons. The fact is that the data provided corresponded to the standards of the manufacturing countries. Which created some confusion in the perception of the material. Confusion caused precisely by poor knowledge of the very concept of “caliber”.
After some thought, I decided to make up for my mistake. Indeed, even those who professionally deal with small arms rarely think about the theoretical part. For what? There are our weapons, there are European ones, there are American ones. And this weapon is used with the appropriate cartridges. When using others, completely unnecessary delays and other troubles arise.
So, let's start with the basics. What is a caliber? Caliber is a numerical expression of the diameter of the bore, measured between opposing fields. Everything seems to be clear. However, currently existing weapons do not always meet this definition. Why did this happen? The thing is that military personnel use rifled weapons in their work. This circumstance makes the standard definition conditional.
For the most part, weapons meet the standard. But there are exceptions. Calibration by rifling is much less common. Simply put, the caliber is determined not by the field of the barrel, but from the depth of the rifling to the opposite depth of the rifling. But that's not all. Very rarely, but a third method of measuring caliber is also used. Along the rifling and field of the barrel opposite to each other.
So the questions that arose were quite correct. Although they arose during the use of weapons. Cartridges of the same caliber “do not fit” or “lobble” in the barrel. But more on that below.
Now about the designation of calibers in different countries.
Many have wondered about the famous Russian three-ruler. Why does this weapon have this particular name? Excellent rifle, 7.62 mm. Why three-line?
The caliber measurement system adopted in Tsarist Russia is to blame. 1 line corresponded to 2.54 mm. The attentive reader has already seen where the legs grow from. That's right, an English inch. 1" = 25.4 mm. But since the calibers of small arms are still smaller, they were divided into lines. 1" = 10 lines. And then simple arithmetic. 3 lines = 7.62 mm.
What I wrote above is a fairly well-known fact. But this fact has a continuation. When discussing the Mosin rifle, another name for the caliber was used: 30 points. Imagine: the “famous Russian thirty-point”... Indeed, this calibration system was also used at that time.
1 inch = 10 lines = 100 dots = 25.4 mm.But let's return to our days. We are still more interested in modern designations of weapon calibers.
In most countries of the world, caliber is expressed in the notation we know. Millimeters. These can be either whole numbers or fractions. Fractional numbers are usually written to the second digit. 9 mm pistol and 5.45 mm machine gun. This notation gives a more accurate determination of caliber.
But the UK and the US retained the caliber designation in inches. By the way, this also applies to other countries where the English system of measures has been preserved. Our “familiar” lines were also preserved, albeit in a slightly modified form.
In the UK, calibers are measured in thousandths of an inch. The Americans simplified the measurement a little. They make do in hundredths.
To fully understand this system, it is still necessary to return to our beautiful three-ruler. Officially, according to English requirements, the caliber of this weapon was recorded as 0.3 (3 lines = 3 x 2.54 mm).
In English notation this caliber will be written as 0.300. In American - 0.30. The zero was removed for convenience, and today we have two remaining calibers: .30 and .300. But even this is most often not used today. You don't need a period either. Calibers today are simply designated 300 in the UK and 30 in the US. But for us this is the well-known 7.62 mm caliber.
30 (USA) = 300 (UK) = 7.62 mm (Russia).
This way it looks clearer. Now you, dear readers, can easily calculate the caliber of any weapon and convert it to a measurement system that is familiar to you.
We multiply the American caliber 30 by 0.254 mm and get our 7.62. We multiply the English caliber 300 by 0.0254 and get the same result.
By the way, I had one more question that tormented one of the readers. Why do Americans use a 5.6 mm rifle, while the Russian army uses a 5.45 mm assault rifle? In principle, I already gave the answer at the beginning of the article. And this answer lies in the caliber measurement technique. I’m not sure, but I think there was someone who wanted to dig into weapons and measure the bullet of our AK-74. Not when she's shot. And right in the cartridge. You will be surprised, but you were shooting with a 5.6 mm caliber. This is the diameter of the bullet itself.
The caliber of Russian weapons is measured according to a standard procedure. From field to opposite field. But if you measure the depth of the rifling, you get the desired 5.6 mm. But what I just described does not apply to all bullets. There are many factors that "reduce" the caliber of a bullet to the caliber of a weapon. And they even make this caliber smaller than the caliber of the weapon. This includes the amount of gunpowder in the ammunition, the hardness of the bullet, the number of rifling in the weapon, and the length of the leading part... The barrel of the weapon is not rubber. And the wear of such a barrel is an order of magnitude higher.
I didn’t want to “climb” into the wilds. But if the need arises, I’ll open up a little bit about this side of modern weapons, namely, cartridges. Today, most users of small arms (meaning rifled military weapons) are confident that the cartridge designation corresponds to the caliber. And, alas, they are wrong.
The cartridge designation corresponds to the caliber of the weapon. No, the calibers of the cartridge and the weapon are very close to each other, but do not completely coincide.
American police officers use 38-caliber revolvers. Using the method I described above, you can easily calculate this caliber in millimeters. 9.65 mm! But such a caliber does not exist in principle. And the cartridges used by the police are nothing more than ordinary 9mm cartridges! And such cartridges are used in weapons whose true caliber is only 8.83 mm.
And what is shown in Hollywood films, when a policeman takes out particularly powerful cartridges from a safe and proudly loads a drum with them, turns out to be, in the light of this article, complete nonsense. The ".38 Special" cartridges used in these revolvers are generally 357 caliber!
By the way, exactly the same thing is happening today with the Kalashnikov assault rifle, popular in the United States. Our cartridges and cartridges made in the USA, as they say, are two big differences. Both in terms of equipment and the caliber (true) of the bullet. But more about this some other time.
In general, the current system for designating weapon calibers is as simple as it is complex. Today it is impossible to count millimeters or inches in a primitive way. Existing weapons, even of the same caliber, have different receivers. The cartridges for most rifles and machine guns are “our own”. Unification, which was discussed quite recently, is becoming a thing of the past. Modern small arms are becoming highly specialized. The use of “foreign” cartridges can lead not only to weapon failure, but also to more dire consequences.