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Weapon Evolution: Exotic Ammo

Знакомство с патронами

Gallery of experimental ammunition. From sleeveless and arrow-shaped, to multi-bullet and underwater.

Invented at the beginning of the 19th century, the unitary cartridge marked the beginning of the revolution in the arms business. Since then, its design has not undergone radical changes, but many attempts have been made to come up with something original, something more perfect.

Sleeveless and jet.

Cartridge with a flying sleeve.

AUPO cartridgeless 9mm cartridge was developed and tested in the first half of the 1980s by Italian designer Bruno Civolani. Especially for this ammunition, the Benelli Armi company designed the Benelli CB-M2 submachine gun.

Эволюция оружия: Экзотические патроны

The 9mm AUPO cartridge consisted of an all-metal head and a hollow, thin-walled rear that had the shape of a cylinder.

Эволюция оружия: Экзотические патроны
The scheme of the impact mechanism and the device of the cartridge of the submachine gun Benelli CB-M2.

The back of the cartridge, made in the form of a "glass", served as a sleeve, inside it there was a propellant powder charge and a charge of a flammable substance located in a circle (capsule charge). The open back of the sleeve was closed by a burning diaphragm, which protected the charge from spillage and moisture during storage.

Эволюция оружия: Экзотические патроны

Ignition of the capsule charge was carried out by hitting the striker on the wall of the cartridge in the vicinity of the capsule composition, while the wall of the sleeve was slightly deformed, but did not pierce through. The charge of gunpowder completely burned out in the bore, while the bullet flew out entirely along with the "sleeve".

Эволюция оружия: Экзотические патроны
Benelli CB-M2
Эволюция оружия: Экзотические патроны
Scheme from a 1981 patent illustrating the operation of the automation of a Benelli CB-M2 submachine gun.

In case of misfire, the edges of the “glass” of this cartridge are slightly bent inward. The hook of the extractor clings to this protrusion. Upon successful ignition, the “sleeve” under gas pressure opens to the walls of the chamber, thereby freeing itself from the extractor hook.

Compressed charge cartridges.

In the early 60s of the last century, the German Ministry of Defense funded a research program for the development and study of shell-free ammunition of intermediate calibers. Development work was carried out by Dynamit Nobel.

Эволюция оружия: Экзотические патроны
From top to bottom: experimental 4.3x21 DAG and 4.7x21 DE11, final 4.73x33 HK.

The ammunition developed by Dynamit Nobel initially had a caliber of 4.3 mm, with the bullet pressed into the front of the varnished powder bomb, to the back of which a combustible capsule was glued. This cartridge had a significant drawback - during intensive firing, the powder charges in the prothrone self-ignite.

Эволюция оружия: Экзотические патроны
Mauser G11 - an experimental model chambered for 4.7x21 DE11, a competitor to the Heckler & Koch rifle of the same name.

In 1975, the design of the cartridge was redesigned, and the caliber was increased from 4.3 mm to 4.75 mm. In December 1978, when the new HITP high-temperature gunpowder was developed, consisting of HMX, cellulose with impurities and viscose threads to increase the mechanical strength of the propellant charge.

The adoption by the NATO bloc of 5.56x45 NATO caliber cartridge meant the loss of the ability to standardize a cartridgeless cartridge in the foreseeable future, and in March 1979 the German government stopped funding the development of the G11.

Dynamit Nobel and Heckler & Koch have continued to develop the G11 and shellless ammunition at their own expense.

In 1981, comparative tests were conducted, during which it was found that a cartridge of 4.7 × 34 mm caliber, having the shape of a parallelepiped and a telescopic configuration, has several advantages compared to previously developed samples. By 1983, the final decision was made to switch to a new cartridge of 4.73? 33 mm caliber.

Эволюция оружия: Экзотические патроны

A new powder based on nitramine with high moisture resistance and heat resistance was developed for him. The capsule composition was enclosed in a copper cup providing chemical isolation of the charge. An accelerating charge of quick-burning gunpowder was placed between the capsule and the bullet. Reducing the leakage of powder gases into the bore in front of the bullet was provided by a plastic cover and a high propellant charge density. To increase the heat resistance of the propellant charge, its surface was subjected to pyrolysis - heat treatment without oxygen. The bullet was coated with molybdenum-based solid lubricant. The development of the final design of the DM11 cartridge was completed by 1987.

In the 80s, the G11 rifle (read more about it here) and cartridgeless cartridges were tested in the USA (as part of the Advanced Combat Rifle research program) and Switzerland. But in both cases, the military chose rifles for ammunition of a traditional design. In 1988, the G11 rifle entered the army tests in Germany, held before 1990. Tests of various modifications of the rifle took place in parts of mountain shooters and airborne. In 1990, the rifle was successfully tested and in September of the same year, a contract was being prepared for the supply of 200 thousand rifles to the troops. But the contract was not approved due to political and economic changes in the country, which was on the verge of unification with the German Democratic Republic, after which the completion of weapons and ammunition were terminated.

Another similar cartridge was developed in the USA by AAI Corporation in the early 1980s, for the Advanced Infantry Weapon System (AIWS - a promising infantry weapons system) program aimed at finding a replacement for the M-16 rifle.

Эволюция оружия: Экзотические патроны

Several modifications of it were developed. The main option was with a 4.3-mm subcaliber bullet with a lead core in a drop-down segment tray.

The propellant charge had a cylindrical shape and consisted of short-cut compressed tubular gunpowder mixed with collodion. A bullet was placed in the front of the charge, and a burning igniter capsule, covered by a rubberized protective pad, was located in the bottom of the charge. The development of a cartridgeless cartridge was discontinued, since the AAI Corporation rifle did not pass competitive selection and showed unsatisfactory results in terms of reliability and accuracy of the battle during the tests.

Bullet Diameter:
4.3 mm
Cartridge Length:
41.44 g
Throwing Length:
31.83 mm
The diameter of the powder checkers:
9.15 mm
Bullet weight:
1.8 mm
Cartridge weight:
4.28 g
Muzzle velocity:
?

Jet Gyrojet

Perhaps the most famous caseless circuit is the jet cartridge for the American MBA Gyrojet pistol.

Эволюция оружия: Экзотические патроны

Gyrojet reactive bullets (13? 50 mm) made of stainless steel had a low initial speed and stabilized only by rotation due to the deflection of part of the powder gases in the radial plane, but the shot was almost silent, and at a distance of 55 m the energy of the accelerated bullet was almost doubled exceeded the energy of a bullet fired from a Colt M1911 pistol.

7.62 mm submarine active-reactive cartridge

In 1967, the USSR Navy ordered TsNIITOCHMASH to develop a complex of underwater weapons for combat swimmers.

The development of an underwater pistol and ammunition for it were begun in February 1968 by Shiryaev D.I. together with Matveykin S.I. - Engineer in the field of development of solid fuel engines. The project was based on the open patent documentation for the Gyrojet pistol.

Эволюция оружия: Экзотические патроны

The cartridge consisted of a long steel tube with a sharp and heavy tip. A solid fuel checker was placed in the tube. From the bottom of the tube, a jet engine nozzle and a steel pan covered the tube. A tin lead belt guiding the initial spin of the bullet led the rocket through the rifling of the barrel. The missile was mounted in a brass sleeve with an expelling charge and a Zhevelo capsule.

The first samples of a pistol and ammunition were ready by July 1968 and tested in Feodosia.

Эволюция оружия: Экзотические патроны
Pistol D.I. Shiryaev and various ammunition to him.

Based on the test results, it was decided to abandon the concept of a jet bullet and switch to creating an ammunition whose stability in water would be ensured by the cavitation effect.

Эволюция оружия: Экзотические патроны
Active-reactive cartridge in disassembly.

The developers abandoned the ignition system of the powder bombs through the throttle hole in the nozzle sleeve of the engine. Instead, a system was developed for igniting a marching powder bomb from the front of the bullet using an inertia-settling capsule and an igniter charge consisting of a charge of black powder of the DRP-2 brand and a tablet of a pyrotechnic composition B6M. The swirling of the first non-cavitating active-rocket missiles along the trajectory was provided by longitudinal saw cuts forming a screw on the head fairing of a bullet. For cavitating rockets, the nose was made of steel or duralumin, had an acute conical shape or the shape of a truncated cone. To accelerate the formation of a gas bubble around the rocket, part of the powder gases was removed from the powder bombs through the holes in the tip of the rocket.

Эволюция оружия: Экзотические патроны

In the end, the active-reactive ammunition was worked out and ensured stable operation at depths of up to 17 meters, at a speed of 200 m / s, ensuring the penetration of four inch pine boards at a distance of 25 meters. At a depth of 20 meters, the missiles quickly lost stability. This problem could be solved by increasing the initial velocity of the bullet by 20 m / s, but by 1970 the work on active-reactive cartridges for an underwater pistol had been curtailed, and a model of an underwater pistol developed by Vladimir Simonov was adopted.

Bullet Diameter:
7.91 mm
Cartridge Weight:
32.0 g
Cartridge Length:
? 210 mm *
Bullet weight average:
26-28.5 g
Gunpowder brand:
The average weight of the powder charge:
?
Muzzle velocity:
200 m / s ***
Average accuracy R 50 at a distance of 5 m:
? 90 cm **
Punching action:
Inch pine board at 10 meters at a depth of 5-40 m
4 inch boards at 25 meters to 17 meters depth

Where:
* - The length of the cartridges fluctuated depending on the modifications.
** - Data for non-cavitating samples.
*** - Data for cavitating samples.

One is good, and two is better. Multi-bullet cartridges.

The SSB (Salvo Squeeze Bore) was first patented in the late 1960s.

Эволюция оружия: Экзотические патроны

SSB is a complex of several submunitions, conical hollow or conventional bullets, which are mounted on each other and secured in a sleeve. This design allows you to combine submunitions, for example, the front can be made of heat-strengthened steel, and the subsequent ones can be made of mild copper or with the addition of tracer composition. SSB has a high stopping effect (OD), because it affects a larger area of ​​the target than a conventional bullet.

Эволюция оружия: Экзотические патроны

Initially, the expensive SBB bullets were not widely used due to the fact that they do not have radical advantages in armor penetration and stopping power over conventional bullets.

In the USSR, TsNIITOCHMASH was engaged in this topic, the duplex cartridges developed there were adopted.

Эволюция оружия: Экзотические патроны
The 12.7x108 / 1SL cartridge was designed for the YakB-12.7 machine gun mounted on Mi-24D helicopters.

The cartridge is equipped with two armor-piercing incendiary bullets 49.4 mm long each. Each bullet consists of a bimetallic shell and a steel core in a lead shirt. The core and shirt are truncated from above, and an incendiary compound is pressed into the formed gap between the core and the shell of the bullet. The first bullet is mounted in the cartridge sleeve with a reinforced crimp into a double flute on the pool. The second bullet is located inside the sleeve, with the bow entering the conical recess of the core of the first bullet, and is additionally attached by the core of the sleeve at three points.

Bullet Diameter:
13.01 mm
Cartridge Weight:
145 g
Cartridge Length:
145.5-147 mm
Bullet Retrieval Force:
250-450 kg
Bullet weight average:
31.0 + 31.0
Grades of gunpowder:
The average weight of the powder charge:
4/1 fl
15.0 g
Patterning battlefield 1st and 2nd bullets R 50 to 300m:
? 50 cm
Bullet Speed ​​V 25 :
710-740 m / s
The maximum pressure of the powder gases:
3100 kg / cm 2
GRAU indices:
9-A-4012

The concept of multi-bullet cartridges was tenacious and repeatedly returned to it. We will still encounter some of these ammunition.

Swept cartridges

According to historical sources, arrows tried to charge smooth-bore weapons in the 17th century, and even these hand-made charges and placed in wooden cylinders gave some advantage in firing range.

Эволюция оружия: Экзотические патроны

The peak of research in this area occurred in the 60s of the twentieth century. In the USSR, NII-61 (later TsNIITOCHMASH) began to deal with this topic. The result of the work was an OPS cartridge (feathered sub-caliber rifle) and an AO-27 assault rifle.

OPS (coded designation 18ELC) consisted of a brass sleeve 43.6 mm long with a capsule of the Berdan system, booms 50 mm long made of steel grade 50 (bullet weight 2.3 g, plumage diameter 7.62 mm, case diameter 3 mm), two-sector pallet weighing 0.2 grams.

The tail feathers of the first arrows were made of plastic, until a relatively inexpensive technology for manufacturing all-metal arrows by stamping was developed. The coupling of the elements of the pallet and bullet was provided due to ring knurling on the boom body and the inner surface of the leading elements. The sub-caliber bullet was guided along the bore by a leading-type pallet with a profile of complex shape.

Tests have shown the working capacity of the development, the complete separation of the leading pallet from the boom at a range not exceeding 50 meters from the muzzle of the barrel, a high initial bullet speed of 1085-1100 meters per second.

According to tests of the “automatic machine - cartridge with an arrow-shaped bullet" complex, at the stage of the chief designer, his advantage over the AK-47 was overwhelming, with the exception of two points - the stopping effect and the cost of the cartridge.

In terms of stopping action, the fledged bullet did not meet the requirements of the military to a large extent, and this alone was enough to leave the topic in the category of research, and the cost of an OPS cartridge was more than twice as high as the regular one.

As a result, the AO-27 assault rifle, and the cartridges for it, remained at the stage of experimental development. The complex with sub-caliber bullets was not adopted for service.

After that, he completed work on the design of such ammunition Dvoryaninov V.N.

Эволюция оружия: Экзотические патроны

Soon the research institutes “Foil” (machine gun) and “Finval” (rifle) were opened, within the framework of which the Izhevsk Machine-Building Plant developed weapons, and TsNIITOCHMASH ammunition with a sub-caliber swept-shaped bullet. Izhmash experts developed a SVD-based sniper rifle and re-fired machine gun SG-43. The machine gun and rifle had their own barrels and muzzle attachments for breaking the pallet elements that separated from the bullet.

Эволюция оружия: Экзотические патроны

During the development, various options for cartridges were worked out: experimental two-bullet and three-bullet arrow-shaped cartridges, tracer bullets and bullets with a different type of tail. According to reports, the production of arrow-shaped bullets was established at the factory number 60 in the city of Frunze, and cartridges were equipped with the use of cartridges of the factory number 188 (Novosibirsk). The latest known samples date back to 1980. According to reports in the open press, the final version of the cartridge with an arrow-shaped sub-caliber bullet had the accuracy of a battle comparable to a gross rifle cartridge with an LPS bullet, but significantly surpassed it in terms of production cost. None of the prototypes of weapons and ammunition went into mass production.

Overseas developments in this area have come along roughly the same path. One of the most famous American feathered munitions is the .330 Amron Aerojet cartridge (8.38x69 mm) tested under the SPIW program.

Эволюция оружия: Экзотические патроны

Cartridges of non-classical layout.

Tround cartridge

In August 1958, David Dardik patented the “open-chamber firearm” (Dardick open chamber gun) - a kind of hybrid pistol and revolver and the so-called tround cartridge.

Эволюция оружия: Экзотические патроны

It was made of aluminum, and then of high-strength plastic, and was originally produced in calibres .38 (9 mm), .30 (7.62 mm) and .22 (5.56 mm), according to their characteristics corresponding to 38 SW Special cartridges .32 SW long and .22 LR, and the sizes of plastic sleeves were the same for all calibres.

Round ammunition could be re-loaded using standard pistol caps 5 mm in diameter, and bullets of the appropriate caliber. The liner had inner annular grooves, limiting the landing of the bullet and providing a boost pressure sufficient to completely burn the powder.

Эволюция оружия: Экзотические патроны
At the top is one of the Gyrojet carbines, at the bottom is the H&R SPIW revolving rifle.

In the course of its development, Dardic’s ammunition underwent a lot of modifications, so among the four main participants in the American SPIW program to develop a promising semi-automatic rifle for a cartridge with a sub-caliber arrow-shaped bullet, a tround cartridge (Harrington & Richardson company) also participated.

Эволюция оружия: Экзотические патроны

5.56x36 Folded

In 1965, design engineer Frankford Arsenal, Andrew Grundy, patented a cartridge of a very unusual shape. A key element of the new concept was the rejection of the classic form of the sleeve with its replacement with a plastic capsule containing a powder charge on the side of the bullet.

Эволюция оружия: Экзотические патроны

Such an unorthodox configuration of the cartridge made it possible to reduce its dimensions and realize the frontal combustion of the powder charge, which allowed us to reduce the erosive effect of powder gases on the barrel bore. Also in theory, reducing the length of the chamber of the weapon reduces the mileage of the moving parts of the weapon, which allows for a higher rate of fire at a lower speed of movement of moving parts, to reduce shock loads and the mass of weapons.

From 1965 to 1983, U-shaped cartridges were tested in various calibres: 4.32 mm, 5.56 mm, 7.62 mm, 12.7 mm and 30 mm, but were never found its army or civilian use.

Cartridge AIWS.

In 1970, Mauri Goldin, the designer of the American company Hughes Tool Company, patented the design of a cartridge with a three-chamber sleeve in the form of a parallelepiped and a system of non-locking weapons.

Эволюция оружия: Экзотические патроны

The bullet in the AIWS cartridge is located in the central chamber, and the powder charge is located in two side chambers. This configuration of the cartridge made it possible to store 54% more ammunition in a given volume compared to traditional ammunition of the same caliber, and also provided significant mass savings, which was comparable to the advantages provided by cartridgeless ammunition. In this case, the plastic sleeve provided the necessary obturation of the powder gases, protecting the propellant charge and capsule composition from environmental influences. The rectangular profile of the cartridge case allowed the development of a high-capacity magazine and a simple, compared to conventional weapons, system for feeding cartridges into the chamber and extraction of the spent cartridge case.

Эволюция оружия: Экзотические патроны

In 1986-88, the McDonnell Douglas Helicopter Company and its weapons division HTC under a contract with Picatinny Arsenal took part in the US Advanced Infantry Weapon System program to develop a promising rifle complex and cartridge for it.

Эволюция оружия: Экзотические патроны

As part of this program, ammunition of a nominal caliber of 8.6 mm was developed (a plastic sleeve containing 2 bullets of 6.0 mm caliber), 11.0 mm with five sub-caliber feathered arrow-shaped bullets and 9.0 mm with three sub-caliber feathered bullets. But the assault rifle did not pass competitive selection, and the development of ammunition was discontinued.

5.56x30 AIWS

Bullet Diameter:
5.7 mm
Sleeve Length:
30.77 mm
Sleeve Width:
23.11 mm
Sleeve Thickness:
7.6 mm
Bullet weight:
4.43 g
Cartridge weight:
9.71 g
Starting speed:
850 m / s

Perforated cartridges

Comp bullet

Эволюция оружия: Экзотические патроны

In this pool with the help of high-precision machines, several interconnected holes are made.

When firing a Comp bullet, powder gases pass through holes in the walls of the bullet and reduce friction against barrel rifling. According to the assurances of the developers, the holes also play the role of a kind of muzzle brake and reduce the recoil from the shot.

7x56 Broadway Trust with perforated sleeve.

Эволюция оружия: Экзотические патроны

In 1941, Sir Dennis Burney, proposed to the British Minister of Supply the project for the development of portable recoilless anti-tank rifles. With the support of the state, the joint company Broad Trust Company (BTC) was founded.

Initially, developments were carried out in the field of designing ammunition with a caliber in the range of 20-88 mm. The use of "hole" sleeves was supposed to reduce recoil when fired to values ​​that allow firing from the hands and to develop a sufficiently powerful and light anti-tank rifle. Gradually, the focus of development shifted to designing smaller-caliber rifles.

After a series of unsuccessful developments of large-caliber recoilless rifles, in 1942, work began on the design of a small-caliber rifle under a 6.35 mm caliber cartridge, but, faced with the difficulty of creating an effective tracer, the cartridge caliber was increased to 7 mm.

The cartridge of 7 mm caliber had a composite (in two parts) brass sleeve of a bottle-shaped form (a version of the cartridge was also worked out with a whole perforated sleeve). Several rows of through holes were drilled at the top of the liner. The upper part of the sleeve was screwed into the lower part, in which a groove was made to form a flange to capture the sleeve with an extractor. In the chamber of the gun, the lower part of the cartridge case was located in its narrow part and expanded at the moment of the shot, providing obturation of the powder gases, and most of the powder gases were etched through the holes in the walls of the upper part of the cartridge case into the chamber of the chamber of increased volume. This made it possible to relieve excess pressure, which ensured a significant decrease in the recoil momentum during the shot.

The cartridge was equipped with a powder charge of NRN 150 brand weighing 9.72 grams, which allowed the bullet to develop an initial speed of 783 m / s. The powder charge consisted of white spherical granules and was equipped in a sleeve in a bag of cellophane. Development and testing continued until March 1948, when a decision was made to stop financing the project, followed by the closure of BTC.

Bullet Diameter: 7.02 mm
Cartridge Length: 76.86 mm
Case diameter: 7.94 mm
Sleeve Length: 56.0 mm
Diameter of sleeve edge: 15.65 mm
Bullet weight: 10.82 g
Cartridge weight: 19.94 g
Starting speed: 783 m / s

Silent ammo

7.62x63 Snake

7.62x63 Snake - one of the special cartridges for silently flameless shooting with a cutoff of powder gases.

Эволюция оружия: Экзотические патроны

In the 50s, at the NII-61, on the order of the KGB of the USSR, work began on the creation of a special silent two-shot pistol and cartridges for it. The complex consisted of a special C4 pistol and a noiseless cartridge PZ (cartridge "Snake").

Эволюция оружия: Экзотические патроны

The cartridge 7.62 mm PZ consists of a steel sleeve with a small taper, inside of which are located: a KVM-3 igniter capsule in a sleeve with a movable striker (screwed into the bottom of the sleeve and providing an obturation of powder gases from the side of the capsule), brand P powder charge -125 and pusher piston. The cartridge is equipped with a bullet caliber 7.62 mm PS.

When fired, the movable striker of the cartridge makes a capsule pierce, which ignites the powder charge. The pressure of the powder gases drives the piston, which pushes the bullet into the bore, giving it an initial flight speed of 170 m / s. When reaching the highest position, the piston abuts against the narrowing of the walls of the liner and stops, providing for the locking of the powder gases inside the liner and the noiselessness of the shot. The length of the spent sleeve with the piston emerging from it is 82.3 mm.

Training and training cartridges

Wooden cartridge 6.5x55 mm Mauser. Of course, he is not able to hit the target - the bullet is completely destroyed when exiting the barrel of a weapon.

Эволюция оружия: Экзотические патроны

Modern training cartridges are often made of plastic.

Training cartridge L14A1 caliber 7.62x54 mm with a tracer bullet. In this cartridge, only the bottom of the sleeve and the inner element of the bullet are made of metal.

Эволюция оружия: Экзотические патроны

Plastic cartridges are used by the military in exercises, in the civilian market they are also in demand - for recreational shooting. They are equipped with a small charge of gunpowder, which makes shooting relatively safe.

The only significant drawback of these ammunition is that in most self-loading rifles and pistols it is necessary to send the next round manually - the automation does not work reliably due to the reduced weight of gunpowder and the small mass of the bullet.

G2R RIP - New Expansive

The expansive bullets themselves are not so unusual, but the latest development of G2 Research definitely deserves its place in this material.

Эволюция оружия: Экзотические патроны

According to press releases, the small teeth of this bullet in flight create a turbulent flow, help stabilize the bullet and make it more accurate, and when hit like a circular saw, clothes, glass, drywall and even sheet metal are cut, allowing the bullet bottom to hit the target more confidently.

Эволюция оружия: Экзотические патроны

G2R RIP - a lead-free, all-copper bullet, weighing 96 grains, is divided into 9 trihedral teeth. Muzzle velocity - 386 m \ s. Muzzle energy - 660 J.

The company G2 Research in the near future expects to begin production of .380 ACP, .357 SIG, .40, .45ACP cartridges, as well as gun cartridges equipped with such a bullet.

The cost of such cartridges is reported to be about $ 2 apiece. In addition to the high cost, the disadvantages of this munition include the potential chance of premature opening of the teeth.

Guided bullet

Sandia National Laboratories product shown to the general public in November 2011.

Эволюция оружия: Экзотические патроны

At the tip of the bullet is a tiny optical sensor that detects a laser beam illuminating a distant target. The microcomputer processes the signal from the sensor and deflects the miniature stabilizer planes, changing the flight path. The bullet is able to independently adjust the flight 30 times per second throughout the flight at a speed of more than 600 m / s. In flight, the bullet is stabilized not by rotation, but by aerodynamic planes, which allows you to more accurately orient the optical sensor and control the flight.

Эволюция оружия: Экзотические патроны

Experimental .45 caliber pistol

Experimental .45 caliber pistol, Czechoslovakia, 1960-70. It seems to be not a fake.

Эволюция оружия: Экзотические патроны
Эволюция оружия: Экзотические патроны

96 grains = 6.22069536 grams

"In the United States and Britain, gran is still used in separate areas. For example, in military affairs (mainly in the field of small arms) to measure the weight of bullets and powder charges."