The largest bullet caliber. What is caliber? Caliber smoothbore and rifled weapons. Caliber one, cartridges differ
The largest is the first caliber. The barrel diameter of a gun of this caliber is 42.42 mm.
| Caliber |
Design diameter |
Actual size used |
| 2 | ||
| 4 | 26,72 | 26,5 |
| 6 | 23,34 | |
| 8 | 21,21 | |
| 10 | 19,689 | 19,7 |
| 12 | 18,59 | 18,2– 18,5 |
| 14 | 17,6 | |
| 16 | 16,834 | 16,8 |
| 18 | 16,186 | |
| 20 | 15,627 | |
| 22 | 15,14 | |
| 24 | 14,7 | 0.577 in or (14.6556 mm) |
| 28 | 13,969 | 14 |
| 32 | 13,36 | 12,5 |
| 36 | 12,847 | 10,4 |
| 40 | 12,4 | |
| 44 | 12,01 | |
| 48 | 11,67 |
We are all used to that calibers rifled combat weapons are indicated by the bore diameter and are expressed in millimeters or fractions of an inch. Moreover, in some countries to determine caliber take the full diameter of the bore, and from us - the distance between the projections of the rifling. Therefore, the diameter of the bullet is 0.2-0.3 mm larger than the caliber of the weapon. So, the bullet of the 7.62-mm intermediate cartridge mod. 1943 of the Elizarov system used in, has a diameter of 7.87 mm, the bullet from the pistol cartridge has a 7.82 mm diameter, and the rifle bullet of the domestic cartridge of the 1908 model has a diameter of 7.9 mm.
However, to indicate calibers smooth-bore hunting rifles, a different system is used: the number caliber means the whole number of spherical bullets that can be cast from one English pound of lead (453.59237 g). In this case, the bullets must be spherical, the same 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 made from a pound of lead. Thus, the twentieth caliber is less than the tenth, and the sixteenth is less than the twelfth.
In the designation of cartridges to smooth-bore weapons, as with the designation of cartridges for rifled weapons, it is customary to indicate the length of the sleeve, for example: 12/70 - a 12-gauge cartridge with a 70 mm long sleeve. The most common case lengths: 65, 70, 76 (magnum). Along with them, there are: 60 and 89 (super magnum). The most widespread in Russia are 12 gauge hunting rifles. There are guns of calibers (in descending order of prevalence) 16, 20, 36 (.410), 32, 28, and the spread of caliber 36 (.410) is due exclusively to the release of Saiga carbines of the corresponding caliber.
The actual bore diameter of a given caliber in each country may differ from those indicated within certain limits. In addition, one should not forget that the barrel of a shotgun hunting weapon usually has of various kinds constrictions (chokes), through which not any bullet of its caliber can go through without damaging the barrel, so in many cases bullets are made according to the diameter of the choke and are equipped with easily cut sealing belts that are cut off when the choke passes.
It should be noted that the common caliber of signal pistols - 26.5 mm - is the very 4th hunting caliber.
Interesting questions sometimes arise in the course of writing and then discussing materials about weapons. This happened after mine and the employees of the security forces. To be honest, it was somewhat unexpected for me.
An interesting conversation arose about the weapons that were used during the tests. More precisely, about the calibers of this weapon. The fact is that the given data corresponded to the standards of the producing countries. Which created some confusion in the perception of the material. The confusion caused precisely by the poor knowledge of the very concept of "caliber".
After some thought, I decided to make up for my mistake. Indeed, even those who are professionally involved with small arms rarely think about the theoretical part. What for? There are our weapons, there are European ones, there are American ones. And this weapon is used with the appropriate cartridges. When using others, unnecessary delays and other troubles arise.
So let's start with the basics.
Gauge is a numerical expression of the bore diameter measured between opposite fields.
Everything seems to be clear. However, existing on this moment weapons do not always fit this definition. Why did it happen? The thing is that rifled weapons are used in the work of military personnel. This circumstance makes the standard definition conditional.
Most of the weapons meet the standard. But there are exceptions. Rifling calibration is much less common. Simply put, the caliber is not determined by the barrel field, but from the rifling depth to the opposite rifling depth. But that's not all. Very rarely, but a third method of measuring caliber is also used. On the opposite groove and the field of the trunk.
So the questions were quite correct. Although they arose already during the use of weapons. Cartridges of the same caliber “do not climb” or “dangle” in the barrel. But more on that below.
Now about the designation of calibers in different countries.
Many wondered about the famous Russian three-line. Why does this weapon have this name? Excellent rifle, 7.62 mm. Why a 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, English inch. 1 ″ \u003d 25.4 mm. But since the calibers small arms still less, it was divided on the line. 1 ″ \u003d 10 lines. And then simple arithmetic. 3 lines \u003d 7.62mm.
What I wrote about 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, at that time this calibration system was also used.
1 inch \u003d 10 lines \u003d 100 dots \u003d 25.4 mm.
But back to our days. We are still more interested in modern designations of weapon calibers.
In most parts of the world, caliber is expressed in the record we know. Millimeters... It can be both whole numbers and fractional numbers. Fractions are usually written down to the second decimal place. 9mm pistol and 5.45mm machine gun. Such a recording gives more precise definition caliber.
But the United Kingdom and the United States have retained the caliber designation in inches. By the way, this also applies to other countries where the English system of measures has been preserved. Preserved, albeit in a slightly modified form, and our "friends" - the lines.
In the UK, calibers are measured in thousandths of an inch. The Americans have simplified the measurement a little. They manage in hundredths.
For a complete understanding of this system, it is nevertheless necessary to return to our beautiful three-line. Officially, according to British requirements, the caliber of this weapon was recorded as 0.3 (3 lines \u003d 3 x2.54 mm).
In the English designation, this caliber will already be written as 0.300. In the US - 0.30. Zero was removed for convenience, and today we have two calibers in the remainder: .30 and .300. But even this is most often not used today. The point is also unnecessary. Calibers today are simply designated 300 in the UK and 30 in the United States. And for us it is the well-known 7.62 mm caliber.
30 (US) \u003d 300 (UK) \u003d 7.62mm (Russia).
So it looks clearer. Now, dear readers, you can easily calculate the caliber of any weapon and transfer it to the measurement system that is familiar to you.
The American caliber 30 is multiplied by 0.254 mm and we get our 7.62. English caliber 300 multiplied by 0.0254 and we get the same result.
By the way, I had another question that tormented one of the readers. Why do Americans use a 5.6 mm rifle, and in russian army 5.45 mm machine gun? In principle, I already gave the answer at the beginning of the article. And this answer is in the method of measuring calibers. I'm not sure, but I think there was a willing person among those who like to delve into weapons who measured the bullet of our AK-74. Not when she's shot. And right in the cartridge. Surprise, but you fired a 5.6 mm caliber. This is the diameter of the bullet itself.
The caliber of Russian weapons is measured according to the standard scheme. From field to opposite field. But if you measure the depth of the grooves, you get the desired 5.6 mm. But what I have just described does not apply to all bullets. There are many factors that "reduce" the caliber of the bullet to the caliber of the weapon. And they even make this caliber smaller than the caliber of the weapon. This is the amount of gunpowder in the ammunition, and the hardness of the bullet, and 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 much higher.
I didn't want to "climb" into the jungle. But if the need arose, I will slightly open this side modern weapons, namely, cartridges. Today, most of the users of small arms (meaning rifled combat weapon) are confident that the cartridge designation matches the caliber. And, alas, they are wrong.
The cartridge designation does not correspond 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 use 38-caliber revolvers. Using the technique I described above, you can easily calculate this caliber in millimeters. 9.65mm! But this caliber does not exist in principle. And the cartridges used by the police are nothing more than regular 9mm cartridges! And such cartridges are used in weapons, the true caliber of which is only 8.83 mm.
And what is shown in Hollywood films, when a policeman takes especially powerful cartridges from a safe and proudly equips a drum with them, in fact, in the light of this article, turns out to be complete nonsense. The .38 Special cartridges used in these revolvers are generally 357 caliber!
By the way, the same is happening today with the Kalashnikov assault rifle, popular in the USA. Our cartridges and US made cartridges, as they say, are two big differences. And in terms of equipment and caliber (true) bullets. But more about that some other time.
In general, the current system of designating the caliber of weapons is as simple as it is complex. It is impossible to count millimeters or inches primitively today. Existing weapons even the same caliber has different receivers. Cartridges for most rifles and machine guns are "ours". The unification, which was talked about 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 the failure of the weapon, but also to more dire consequences.
Edited 31.08.2019
Caliber - the diameter of the bore along the grooves or fields; one of the main quantities that determine the power of a firearm.
The classification of small arms calibers is as follows:
- small-bore (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 shells (bullets), the caliber is determined by their largest diameter
Conical bore guns are characterized by inlet and outlet calibers.
Caliber for smoothbore weapons
For smooth-bore weapons, the caliber number refers to the whole number of spherical bullets that can be cast from 1 British pound of lead (453.59 g). In this case, the bullets must be spherical, the same 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 made from a pound of lead. Thus, the twentieth caliber is less than the tenth, and the sixteenth is less than the twelfth.You can also use the formula for determining the caliber (K) by the barrel diameter (D, cm):
In the designation of the caliber of cartridges for smooth-bore weapons, it is customary to indicate the length of the case, for example: 12/70 - a 12-gauge cartridge with a 70 mm long sleeve. Most common case lengths: 65, 70, 76 mm (Magnum); along with them there are 60 and 89 mm (Super Magnum).
The chamber length in millimeters for hunting smoothbore guns is shown below.
The actual bore diameter of a given caliber depends, firstly, on the specific manufacturer and, secondly, on the drilling for a certain type of 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 is 19.4 mm. In addition, one should not forget that the barrel of a shotgun hunting weapon usually has various types of muzzle constrictions (chokes), 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 supplied with centering belts that easily wrinkle when passing the choke.
It should be noted that the common caliber of flare pistols 26.5 mm is nothing more than the 4th hunting caliber.
Caliber for rifled weapons
Caliber for rifled weapons in fractions of inches (English system)
The caliber of rifled small arms in countries using 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 in.)In notation, the integer zero and the unit designation (inches) are omitted, and a point is used as the decimal separator. For example, .45, .450. In Russian texts, traditional English and american calibers written in the same way (with a point, not a comma, adopted in Russia as a decimal separator): caliber. 45, caliber. 450
In colloquial speech, only fractions of an inch are spoken: forty-fifth gauge, four hundred and fifty gauge.
In the West, for civilian cartridges, the caliber is usually added to the name of the company or standard of the cartridge: .45 Colt, .41 S&W, .38 Super, .357 Magnum, .220 Russian.
Caliber for rifled weapons in 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 case is added through the multiplication sign: 9 × 18 mm.It should be borne in mind that the length of the 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 sleeve lengths.
In the West, this digital notation is used mainly for army cartridges.
Caliber for rifled weapons in lines
In Russia until 1917 and in a number of other countries, the caliber was measured in lines. One line is 1/10 inch (0.254 cm or 2.54 mm). In modern speech, the name "three-line" is rooted, which literally means a rifle of the 1891 model (Mosin system) of three-line caliber (ie 7.62 mm or, if you are interested, .30).
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 given state of affairs is due to the fact that almost every arms company has its own patented cartridges different characteristics, and the foreign cartridge adopted for service or for civilian circulation receives a new designation
Caliber Comparison Chart
In general, calibers are recalculated assuming that 1 inch (1 ") equals 25.4 mm.But it should be borne in mind that in different countries the caliber is measured in different ways (by the fields or the bottom of the grooves). In addition, the designation of the caliber of the cartridge can be conditional - for example, the 22LR and 2222Rem cartridges actually have the same caliber, but they radically differ in type (the first is rimfire, the second is central) and the size of the case. Likewise, the .38 and .357 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.
Hello. Please tell me the real caliber of this howitzer. As far as I know, the choke is anything larger than the 12th. Somewhere I found an article about 4-gauge elephants. Four ball bullets from a pound of lead. It doesn't fit in my head. These are already, perhaps, the cores. Vitaly Galiskhanov.
Photo by Evgeny Kopeiko
Of a pound of lead, the four ball bullets are really 113g shells for an antique quarter-pound cannon.
But from hunting weapons, even large-caliber, such colossal bullets were not fired and do not shoot.
It is not only a matter of calculating the caliber of a weapon by the number of round bullets, but also of the actual size of the shells of a hunting weapon.
A hunting fitting is a rifled weapon with a folding block of barrels of the same caliber (traditional) or different (the so-called "mountain").
It doesn't have to be more than 12 or 729 inches. Of the modern ones, the smallest is the Peter Hofer fitting in 17WMR caliber, and the largest is the Holland-Holland Royal fitting in the 700N.E. caliber, or the same Verney-Carron, or Ziegenhahn.
By the way, the rifled caliber. 700N.E. very close in diameter to 14 gauge. It is the large-caliber Verney-Carron fitting presented by the company at the Moscow exhibition ARMS & Hunting-2017 in Gostiny Dvor.
A large-caliber hunting weapon can be of any kind, both smooth-bore guns and fittings, the caliber is a parameter of the barrels, and not a characteristic of the type of weapon.
In the year before last - XIX century, fittings and larger calibers were produced for cartridges with black powder, the calibers of these weapons were calculated by the number of round bullets cast from one pound of lead according to the British measurement system, that is, weighing 453.6 grams.
But the bullets for these "elephant" and other fittings were not necessarily ball-shaped, as a rule, they were of an obturable design and weighed less than the nominal ball.
Large smoothbore guns were of the 10th, 8th, 4th, and even 4th calibers. The essence of these large-caliber samples lies in their purpose, they were fired, as a rule, with a shot, and, if necessary, with a bullet.
Among them were the so-called "wefts" for hunting in places of accumulation of waterfowl. These are heavy guns, and especially large ones were fired from special stops mounted on a boat or in ambush.
But it is not at all necessary that shells of nominal caliber were fired from large-caliber rifles.
Nowadays, a 45 g round for a 12-caliber Mag is not surprising; there are also magnum-category shotguns and cartridges on sale, and this is a 10-caliber round. And then a shell of such a mass was almost the limit, not everyone dared to shoot heavy shells.
But there were, and still are, typical hunting large-caliber rifles, these are samples of a traditional design with a folding block of barrels, of course, heavy and brutal, but the somewhat smaller mass of which to some extent allows you to shoot from your hands. Usually these are guns of the 10th and 8th caliber, they were produced in different countries.
Let me remind you that the nominal diameter of the 10-gauge bore is 19.69 mm, and the 8-gauge bore, respectively, 21.21 mm. Shotguns of the 10th and 8th calibers are not uncommon in the late 19th - early 20th centuries, hunters needed models for large shot shells.
The chambers did not exceed 85 mm in length, a shot projectile was placed in such a sleeve up to the nominal. They not only hunted with them, but even shot at the "pigeon" cages.
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Photo by Anton Zhuravkov. |
And our plant ITOZ produced a single-barreled breech-loading hammer "weft" 10-caliber with a folding barrel, as well as an 8-caliber with a barrel length from 890 to 980 mm.
They cost much more, 30 and 50 rubles, respectively, in terms of the 1911 exchange rate, than the same smaller 12-gauge gun offered for 26 rubles. Prices and photos 2 and 3 are taken from "Prices No. 9 for 1910/11 of the A.A. Bitkov in Moscow "from my archive.
By the way, the Tula firm TsKIB SOO also produced a 10-caliber MTs10-10 double-barreled gun. Now I will only remind you of its main parameters: the barrels are heavy, weigh 1.9 kg, the shoe is steel, the weight of the gun is 4.13 kg.
Pay attention to the length of the chamber - 70 mm; this gun is intended for firing only shot with nominal caliber of projectile weighing 45 g or less, but no more. The permitted pressure is indicated by the inscription “no more than 700 kg / cm2” on the barrels.
It is obvious that this solid double-barreled shotgun, despite its mass, does not belong to the now widespread category of "magnum".
Once upon a time in Moscow, a Belgian hunting horizontal line of 8 caliber was offered, massive, but very interesting and in very good condition. The design is typical, a reclining block of barrels, locks in the block, triple locking of the block of barrels, a stock with a pistol neck shape.
Of course, you can shoot from such a double-barreled shotgun once or twice, and then put it on your backpack in order to focus and gather strength before the next doublet. It had to be abandoned, but only due to the lack of branded sleeves, now it is no longer possible to find them, except that they can be collected individually at specialized auctions abroad.
Such a rare gun needs real factory shells with a paper shell, not homemade ones.
By the way, the absence of shell casings made it in good condition, since the former owner had nothing to shoot with.
As an example of a very large-caliber hunting weapon, the old French 4-caliber single-barreled muzzle-loading gun made in 1830-1840s in Saint-Etienne deserves attention.
Its weight is only 3.0 kg with a barrel length of 700 mm, and the bore diameter of the 42 caliber corresponds to 26.72 mm in the metric system. However, no one was ever going to shoot from it with a nominal caliber of shot shells, this would have amounted to 113 grams each time.
Neither this gun with very ordinary parameters, nor the hunter himself, due to excessive recoil, would have withstood such shooting.
In fact, this is a small elegant gun, albeit a 4-gauge, it was created with the aim of obtaining a wide talus of shot at the usual distance of 35 meters when shooting shells of shot no more than 36 grams familiar to a hunter of average physical capabilities.
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Photo by Evgeny Kopeiko |
Despite its colossal 4 gauge, this Saint Etienne antique ramrod with capsule lock is a typical Western European hunting rifle of the second quarter of the 19th century.
So in the Museum of Saint-Etienne, I examined a muzzle-loading double-barreled gun of 1836-1840. local production with the same stock, decorated in the style of "rocaille", safety clip, semicircular hammers on the capsule lock. A similar gun of similar decor and design is in the Liege Museum.
Unfortunately, the photos of the Saint-Etienne single-barreled 4-caliber were mediocre, and the owner wished to remain incognito, so you will have to limit yourself to just a slightly more detailed description.
It is important that the barrel on it is steel, very strong, although it would be more logical to see a Damascus barrel on a gun of that period. The length of the steel barrel is only 672 mm, and with a breech screw it is equal to 701 mm, which is quite a bit for a 4-gauge rifle, but fully corresponds to its purpose - to create wide talus at a normal distance.
In the breech, the barrel is octahedral, in the middle with a large number of edges, there are sixteen of them, and in the last third of the length to the barrel is round. Cap lock with a spectacular semicircular trigger. All parts are steel, from the breech and the lower face-base of the trigger to the safety guard and butt pad with a long upper shank.
The stock is long, with a projection under the cheek and a semi-pistol neck, decorated with carvings in the style of "smooth rocaille". Branded swivels indicate that this gun was supposed to be worn on the hunt.
The Saint-Etienne 4-gauge single-barreled rifle is an expensive tailor-made self made high class. The trunk is decorated with gold in the Empire style floral ornament in the form of lianas, leaves and flowers, among which two fabulous birds in the French style are also depicted in gold, we call them firebirds.
Decorated with engraving and steel parts of the gun, right up to the breech and trigger. The ramrod in the muzzle-loading model is a necessary and trivial item, without it the gun cannot be loaded, but the varietal solid wood, the horn tip and precise accurate work allow it to be attributed to the decorative elements of the gun.
Now the old guns of the 10th and 8th calibers have supplanted the modern models of the "magnum" category, but the owners of the surviving large-caliber models keep them carefully and shoot, loading cartridges into the branded casings from the previous stocks.
You can ask your question to Evgeny Kopeiko by email: [email protected]
When applied to a rifled weapon, caliber is a numerical expression of the bore diameter measured between opposing fields, or (which happens much less often) the rifling. Even less common is measurement along the opposite groove and the groove field of the barrel. In most countries, the caliber rifled weapons expressed in millimeters and its fractions (usually accurate to the second decimal place when written as a decimal fraction).
In the UK and the USA, as well as in countries where the English system of measures is adopted, the caliber is indicated in fractions of an inch - in thousandths in Great Britain and in hundredths in the United States, and the written designations have a peculiar form - a decimal is written as an integer with a dot in front ( for example, the designation of the caliber "three lines" - 0.3 "\u003d 7," 62 mm, has the form 30 or 300).
The caliber is also indicated in the lines, the ratios are as follows: 1 "\u003d 25.4 mm, 1 line \u003d 2.54 mm; and in points: 1 inch \u003d 10 lines \u003d 100 points. So, the three-line rifle SI. Mosin has a caliber 3x2.54 \u003d 7.62 mm, and the calibers of the three lines, .30, .300, 7.62 are equal to each other. recent times a dot in front of the designation of calibers in England and the USA is not put.
For example, caliber .30 USA should be multiplied by 0.254, and English caliber. 300 by 0.0254 g. As a result, we get that caliber .30 USA is 30 x 0.254 \u003d 7.62 mm, and English caliber 300 is 300x0.0254 \u003d 7, 62 mm. Similarly, caliber. 410 corresponds to 10.41 mm.
In rifled weapons, the bore diameter is measured either by rifling or by fields. Therefore, the same caliber can be designated in different ways. So, the caliber of 9 mm for the "Los" carbine is indicated by the fields (9 mm), and the TOZ-55 "Zubr" fitting - by the rifling (9.27 mm). The caliber of a 5.6 mm rifle is sometimes referred to as 5.45 mm: the first is a change in caliber along the rifling, the second is along the fields. The three-line cartridge 7.62x53R has a leading part of the bullet 7.92 mm in diameter. In general, the diameters of the leading parts of the bullet are larger than the caliber of the primordially domestic cartridges. The diameters of bullets for rifled weapons always exceed the diameters of the barrel bores (for the possibility of cutting into the rifling and acquiring a rotational movement). The excess of the bullet diameters over the barrel bore diameters is far from the same, since they depend on many reasons (depth, shape and number of rifling, bullet hardness, length of its leading part, quality of powder, etc.).
It is clear that of the aforementioned several numbers obtained from various measurements of the rifled bore diameters, as well as the bullet diameter, only one will correspond to the indicated caliber. Usually this number refers to one of the measurements of the bore, so the indicated caliber of rifled cartridges is essentially the caliber of the weapon for which these cartridges are intended. The true dimensions of the bullets never correspond to the indicated caliber. Only in those cases when there is a measurement of the caliber of a weapon by rifling, the designated calibers of the weapon and the true diameters of the bullets turn out to be very close to each other, close, but still different. To what has been said, it should be added that among the designations of calibers there may be found those that do not correspond to the size of either weapon or bullets. They are just traditional and do not act as information about the size, but as a symbol of this or that particular cartridge. As a result, a mixed designation system has been adopted in world practice, in which a given cartridge is designated as it was designated in the country that issued it.
Perhaps the only prerequisite is the presence of information about its caliber in the name or designation of the cartridge. Usually, the designations of calibers in the inch system are not translated into millimeters, since they are often either approximate or conditional, being only a symbol of a given cartridge, and not a carrier of information about the true value of the caliber. So, with a formal translation into millimeters, for example, notation. 38, the value is 9.65 mm. But this is a non-existent caliber - a conventional designation. 38 actually have 9-mm cartridges used in weapons with a true caliber equal to 8.83 mm. Perhaps only experts know that the .38 Special revolving cartridge uses .357 caliber bullets. "The main reason for the discrepancies, as mentioned above, is the measurement of the bore diameter - by rifling or by fields.
Strictly speaking, the caliber of a cartridge is the caliber of the weapon from which the cartridge is intended. The caliber of the bullet itself practically never coincides with that indicated in the name of the cartridge, since its diameter is always greater than the diameter of the gun barrel bore, measured "along the fields." For most cartridges developed in Europe, their name includes the numerical value of the caliber in millimeters, and for cartridges created in the United States and England, the name indicates the caliber in hundredths or thousandths of an inch. Although there are exceptions to this rule. For example, a purely European cartridge .30R Blaser (.30 Air Blaser) received a typical Anglo-American designation, and in the name of American cartridges 7 mm Remington Magnum (7 mm "Remington Magnum") and 7mm-08 Remington (7 mm-08 "Remington") 19 gauge is indicated according to European traditions - in millimeters.
The name of European cartridges, in addition to the caliber in millimeters, usually indicates the length of the case in millimeters and its type - 7x64, 7x65R, 7x57R. The letter R means the presence of a protruding lip - flange. The name of the developer company is often added to catalogs - 7x64 Brenneke, 7x65R Brenneke. The designation of Russian cartridges is also built on this principle, however, as mentioned above, the diameters of the leading parts of the bullet for domestic cartridges are larger than the caliber. So, our 7.62x39 mm cartridge is actually loaded with 7.87-7.92 mm bullets, with the exception of its variants produced in the USA, which use conventional 308 bullets, i.e. 7.62 mm.
A certain specificity is found in the designation of old big bore English cartridges for smoky and smokeless powder. Since all these cartridges had a rim, the designation of the sleeve type was not indicated. So, .450-3 1/4 Rigby denotes the caliber in thousandths of an inch (.450), the length of the case in inches (3 1/4) and the company that produced this cartridge and / or weapon for it.
The 577 Nitro Express (3 "& 2 3/4") cartridge had two options of equipment - a 3 "(76.2 mm) long sleeve and a 2 3/4" (67.7 mm) long sleeve.
In the designation of American and British cartridges, there is no information about the length of the case, and after the digital designation of the caliber, the name of the developer follows: .375 A-Square, .300 Dakota, .300 Holland & Holland, .308 Winchester.
Caliber and surname of the designer who created this cartridge. More often found in the designation of American cartridges. So, one of the most powerful hunting revolving cartridges. 454 Casull (.454 "Casull") was created by Richard Casull, or rifle. 300 Jarrett (.300 "Jarrett"), developed by Kenneth Jarrett. The name of Weatherby's most famous cartridge, the .300 Weatherby Magnum (.300 Weatherby Magnum), contains both the name of the firm and the surname of its developer, Roy Weatherby.
The double hyphenated designations are historically characteristic of American patrons. So, at the time of black powder (almost until 1890) in the designations of the type 44-40, .45-70, the first number showed the nominal value of the caliber, and the second - the size of the charge of black powder in grains (1 grain \u003d 64.8 mg). However, created in 1895, the first American rifle cartridge for smokeless powder - .30-30 - also retained this principle in the name. The most notable exception to this rule is the famous cartridge .30-06 Springfield (.30-06 "Springfield"), in the designation of which the numbers 06 indicate the date of its adoption by the US Army in 1906.
Most of the modern double designations are associated with the fact that a particular cartridge was created on the basis of an existing case. The creators of such ammunition are often single designers - enthusiasts who manufacture them in limited quantities for use in weapons of their own systems. (The so-called "wildcat" cartridges). For example, the .25-06 is a nominal .25 caliber cartridge based on a .30-06 case crimped under a .257 bullet. The .22-250 cartridge with a .22 caliber bullet is based on the .250 Savage (.250 Savage) cartridge case. The designation of the new cartridge .30-378 Weatherby (.30-378 "Weatherby") refers to another cartridge - .378 Weatherby (.378 "Weatherby"), the case of which was used as the base.
When creating the cartridge 7mm-08 Remington (7mm-08 "Remington"), loaded with bullets with a diameter of 284, a re-crimped sleeve was used. 308 Winchester (.308 "Winchester").
England has its own designation system for "converted" cartridges, which is completely opposite to the American one. If the American cartridge .388-.378 Weatherby Magnum has caliber .388 and is based on the re-crimped cartridge case. 378 Weatherby Magnum, then the British would call such a cartridge .388 / .338. The English .500 / .465 Nitro Express cartridge is a .65 caliber cartridge that uses a re-crimped .500 NE cartridge case, similarly. 500/416 refers to a .416 caliber bullet cartridge based on a .500 NE cartridge case. Express (Express) and Nitro Express (Humpo Express).
Some British cartridges have two equipment options: a less powerful black powder, designed for older guns, and a more powerful smokeless powder, designed for modern, more durable weapons. The latter options are designated Express or Nitro Express, which suggests that such a cartridge throws a bullet as quickly as the train of the same name rushes.
Particularly powerful cartridges that develop an excessively high pressure of powder gases when fired in the barrel of a weapon have the definition Magnum ("Magnum") in their name: .222 Remington Magnum, .300 Winchester Magnum, .338 Lapua Magnum (.338 "Lapua Magnum" ). Until the early 1980s, the word "magnum" was usually present in the designation of cartridges, especially American ones. Modern magnums and ultramagnums may not have these names, designers, but only assign them figurative names (300 Pegasus) or their own names and initials (300 Jarret, 375 JRS).
Also, at the present time it is already difficult to assert that the so-called "search" design of the sleeve is a prerequisite for the inclusion of a cartridge in the magnum group with the assignment of the term "magnum". Two other criteria play a significant role - bullet pressure and velocity. Some European high-speed magnum cartridges have the letter 5 in their designation: 5.6x61SE, 6.5x68S, 8x68S.
Some designers give their cartridges fancy names of their own, such as .300 Pegasus, .338 Excalibur and .577 Tyrannosaur (cartridges by Arthur Alfin, firm A-Square), apparently wanting to emphasize their unique speed and power. Abbreviations in names. When writing, to save space (especially when marking on the caps of the cases), abbreviations are often made in the designation of cartridges. For example, the name of the .44 Remington Magnum revolving cartridge (.44 "Remington Magnum"), due to its widespread popularity and the lack of similar competing cartridges in the production, is increasingly being shortened to .44 Magnum or simply .44 Mag. Also, the names of well-known companies that are present in the official designation of the cartridge are usually abbreviated: Winchester - Win (Vin), Remington - Rem (Rem), Weatherby - Wby (Double-B-Wye).
As you can see, various notation systems are very arbitrary and therefore do not allow calculating the real capabilities of the cartridge, based on its name. It happens that a large caliber cartridge with a long sleeve, such as the 9.3x72R, is actually not at all as powerful as one might expect. The energy of his bullet at a distance of 100 m from the muzzle is three times lower than that of a bullet cartridge of a much smaller caliber. 300 Weatherby Magnum (.300 "Weatherby Magnum"). The difference is about 3500 J, which is comparable to the muzzle energy of the .308 Winchester cartridge (.308 Winchester).
Over time, the concepts of "weapon caliber" and "cartridge caliber" became more capacious, expanding to the full designation of the cartridge. This is quite logical, since different models of weapons with barrels of the same caliber can, differing in the shape of the chamber, be designed to use completely different cartridges with casings of different sizes and shapes. Therefore, a purely numerical designation of the caliber, without the usually accompanying additions, is now used only in relation to the bullet itself. Instead of the vague wording "7.62 mm hunting carbine", another, more accurate and informative one is increasingly used - "the carbine (or cartridge) of 7.62x51 caliber".
As you know, cartridges of the same caliber, even with the same diameters of the leading parts of the bullets, but with casings of different sizes and shapes, with flanges or grooves near the bottom, are absolutely non-interchangeable. In addition to the inconsistency of the casings, the non-interchangeability of cartridges is associated with the quantity and grade of gunpowder. So, the amount of gunpowder determines the pressure of the powder gases at strictly defined values \u200b\u200bof the weight and diameter of the outer part of the bullet, diameters along the grooves and fields of a particular gun, and the material of the bullet shell. For example, you cannot use the spherical nitroglycerin powder used in the 7.62x51 cartridge to reload the 7.62x53R cartridges. Nitroglycerin spherical gunpowder in a cartridge 7.62x51 with a semi-shell bullet weighing 9.7 g raises the pressure of the powder gases when fired to 3400 kgf / cm2. If this charge is poured into a 7.62x53R cartridge case, which uses a 13 g bullet, the pressure rises even higher and can destroy the weapon. The weapon chambered for 7.62x53R is designed for a working pressure no higher than 3150 kgf / cm2.
Hunters should be aware that bullets of the same rifled caliber are not interchangeable in many cases. So, the diameter of the bore on the rifling domestic weapons chambered for 7.62x51 is 7.83 mm, and for cartridge 7.62x53R, the diameter of the leading part of the semi-sheathed and combat bullets is 7.92 (the diameter of the barrel bore for this cartridge is also 7.92), that is, more. If the hunting semi-enveloped or combat bullet of the 7.62x53R cartridge is removed and inserted into the 7.62x51 cartridge, then when fired, this will lead to a sharp jump in pressure, which in turn can lead to the destruction of the weapon. Considering that the 7.62x53 semi-shell bullet weighs 3.3 g more, then such a shot is life-threatening. Foreign manufacturers always indicate the diameter of the bullet.
Trofimov V.N., Trofimov A.V. “MODERN HUNTING AMMUNITION for rifled weapons. CASES, GUNPOWDER, CAPSULES, BULLETS, CARTRIDGES, BALLISTICS ELEMENTS "