Off-center bullets: reality and myths, the principle of operation

2024 Author: Henry Conors | [email protected]. Last modified: 2024-02-12 02:39

People who are familiar with weapons know the legends about bullets with a displaced center of gravity. The essence of most comes down to one thing: a chaotic trajectory of movement allows the bullet to pass through two holes spaced apart in the body. Such legends are told in all seriousness and with burning eyes. Is this really so, are there bullets with a displaced center of gravity and what is the principle of their action?

Cartridges with a shifted center of gravity - what is it?

The answer to the question of whether there are bullets with a displaced center of gravity has long been beyond doubt. In 1903-1905, blunt bullets for rifles were replaced by pointed analogues of two types: light ones, which allow firing at close range, and heavy ones, designed for firing at long distances. In comparison with blunt-pointed bullets, such bullets had better aerodynamic characteristics. The leading countries of the world adopted them almost at the same time with some differences: heavy ammunition first appeared in France, England and Japan, and light ones - in Russia, Germany, Turkey andUSA.

History of Appearance

Lighter bullets had a number of advantages except for improved aerodynamics. The reduced weight of the bullet made it possible to save metal, which was beneficial given the huge volumes of ammunition produced. The reduction in mass led to an increase in initial speed and improved ballistics, which affected the range of the shot.

Based on the experience of military operations at the turn of the 19th-20th centuries, the maximum range of firing by fighters with an average level of training was determined. An increase in the effectiveness of aimed fire at a distance of 300-400 meters became possible after the introduction of lightweight bullets without changing the training of shooters. Heavy bullets were used to fire at long distances from machine guns and rifles.

Rifles, designed for blunt bullets, during the fighting showed a lack of light pointed bullets. The sloping rifling of the weapon barrels was not enough to stabilize light bullets, which led to their instability in flight, a decrease in penetration stability and accuracy, and an increase in drift under the influence of a side wind. The stabilization of the bullet in flight became possible only after the artificial transfer of its center of gravity closer to the rear. To this end, the nose of the cartridge was deliberately lightened by placing a light material in it: fiber, aluminum or cotton mass.

The most rational way out of this situation was found by the Japanese, who created a shell of bullets with a thickened front. This made it possible to find a solutiontwo tasks at once: to shift the center of gravity back due to the lower specific gravity of the shell material than that of lead, and to increase the penetration ability of the bullet due to the thickening of the shell. The innovation introduced by the Japanese and laid the foundation for bullets with a displaced center of gravity.

The reason for shifting the center of gravity of the bullet was rational and aimed at improving stabilization, but not at all to achieve a chaotic trajectory of movement and inflict maximum damage when it hits the body. When hit in the tissues of the body, such ammunition leaves neat holes. If the question of whether there are bullets with a displaced center of gravity can be considered closed, then questions about the nature of the injuries inflicted by them remain open, giving rise to myths and legends.

Pattern of damage

What is the reason for the myths about bullets with a displaced center of gravity and a chaotic trajectory of their movement? Do they correspond to reality, or are they just stories and legends?

The first serious, compared to small caliber, bullet wounds were witnessed after being hit by a 7mm.280 Ross round. The cause of extensive damage was the high initial velocity of a bullet with a displaced center of gravity - about 980 m / s. Tissues hit by a bullet at this speed are subjected to water hammer. This led to the destruction of bones and nearby internal organs.

The M-193 bullets supplied for the M-16 rifles did heavier damage. An initial speed of 1000 m / s endowed them with the properties of hydrodynamicblow, but the severity of the injuries was explained not only by this. Bullets, when they hit the soft tissues of the body, travel 10-12 cm, unfold, flatten and break in the area of the annular groove necessary for landing the bullet in the sleeve. The bullet moves bottom forward, and the fragments formed during the break hit the surrounding tissues at a depth of 7 cm from the bullet hole. Internal tissues and organs are exposed to the combined effect of hydraulic shock and fragments. As a result, small-caliber bullets leave entry holes with a diameter of 5-7 centimeters.

Initially, the reason for such an action of a bullet with a displaced center of gravity M-193 was considered unstable flight, associated with excessively flat rifling of the M-16 rifle barrel. The situation could not be changed after the creation of a heavy M855 bullet for the cartridge 5, 56x45, designed for steeper rifling. The stabilization of the bullet was successful due to the increased speed of rotation, however, the nature of the injuries remained unchanged.

It is logical that the action of a bullet with a displaced center and the nature of the wounds inflicted by it do not depend in any way on a change in the center of gravity. Damage depends on bullet speed and other factors.

Classification of bullets in the USSR

The system of classification of ammunition adopted in the USSR has changed over different periods of time. There were several modifications of the 7.62 caliber rifle bullet released in 1908: heavy, light, incendiary, armor-piercing, tracer, armor-piercing incendiary, differing in the color designation of the bow. Versatilitycartridges allowed the release of several of its modifications at once, used in carbines, rifles and machine guns. The weighted variant, hitting targets at distances over 1000 meters, was recommended for sniper rifles.

Sample 1943 (caliber bullet 7, 62 mm to the intermediate type of cartridge) acquired one new modification, having lost two old ones. A bullet with a displaced center of gravity was produced in several versions: tracer, standard, incendiary, armor-piercing incendiary, low-velocity. Weapons equipped with PBBS - a silent and flameless firing device, were loaded only with the latest modification.

Expansion of the range of ammunition occurred after the introduction of caliber 5, 45 mm. The reclassified offset bullets included 7H10 increased penetration, steel-core, low-velocity, tracer, blanks, and armor-piercing 7H22 ammunition. Bullets for blank cartridges were made of a brittle polymer that completely collapses in the bore when fired.

NATO marking and classification

The classification of small arms bullets adopted in the countries of the USA and Europe differs from that in the USSR. NATO color coding for off-center bullets also varies.

LRN

Capless all-lead bullet - the cheapest and earliest modification. Practically not used today, the main scope is sports target shooting. Has a high stopping poweraction in case of damage to manpower due to deformation upon impact. The chance of a ricochet is almost minimal.

FMJ

The most common and best known type of jacketed bullets. Used in all types of small arms.

High strength sheath made of brass, steel or tombac, core - lead. High momentum is achieved by the mass of the core, good penetration is provided by the shell.

JSP

Semi-shell bullets made of lead-filled "glass" with a rounded or flat nose molded from it. The stopping power of this type of offset bullet is greater than that of the jacketed bullet, as the deformation on impact occurs in the nose, which increases the cross-sectional area.

Bullets practically do not ricochet and have a low barrier effect. Prohibited for use in military operations by international conventions. Can be used for self-defense and police units.

JHP

Half-shell bullet equipped with an expansion notch. The structure does not differ from the semi-shell, but it has a molded recess in the bow, designed to enhance the stopping effect.

The action of a bullet with a displaced center of gravity of this type, when hit, is aimed at "opening" with an increase in the cross-sectional area. It does not cause penetrating wounds, when it enters soft tissues, it causes significant damage and severe injuries. The prohibitions on use are the same as for the semi-shell bullet.

AP

An armor-piercing bullet consisting of a hard alloy core, lead filler, brass or steel jacket. The latter is destroyed when the bullet hits the target, allowing the core to pierce the armor. The lead not only provides momentum, but also lubricates the core to prevent rebound.

THV

Achieving high speed and sharp deceleration of a monolithic high-velocity bullet when it hits a target with subsequent transfer of kinetic energy is possible due to the inverse envelope shape. Sale to civilians is prohibited, used only by special units.

GSS

Bullets with controlled ballistics. Consist of shot filler, shell and bow. They are used to fire at targets that are not protected by armor, in conditions requiring accurate hits without through penetrations and ricochet, for example, when firing in the cabin of an aircraft. The destruction of the bullet occurs when it hits the body, followed by the formation of a stream of fine shot, causing severe injuries. It is used in the work of counter-terrorism units.

Soviet response to NATO

It turns out that the answer to the question of whether there are bullets with a displaced center of gravity is unambiguous, but the emergence of myths and legends about their properties defies explanation.

In response to the adoption by NATO countries of the cartridge 5, 56x45, the Soviet Union created its own cartridge of reduced caliber - 5, 45x39. The cavity in the bow deliberately shifted its center of gravity back. Ammunition receivedindex 7H6 and was widely used during the fighting in Afghanistan. During the "baptism of fire" it turned out that the nature of the wounds and the principle of operation of a bullet with a displaced center of gravity are strikingly different from those of the M855 and M-193.

Unlike small-caliber American bullets, the Soviet one, when it hit soft tissues, did not turn tail forward, but began to randomly turn over as it advanced in the wound channel. The destruction of 7H6 did not occur, since the strong steel shell dampened the hydraulic loads during movement in the tissues.

Specialists believe that the shifted center of gravity became the reason for such a trajectory of a bullet with a shifted center of gravity 7H6. The stabilizing factor ceased to play its role after the bullet hit the body: it slowed down its rotation. The reason for further tumbling was the processes occurring inside the bullet. The lead shirt, located close to the bow, shifted forward due to sharp braking, which additionally shifted the center of gravity and, accordingly, the points of application of forces during the movement of the projectile in soft tissues. Do not forget about the bending nose of the bullet itself.

The complex and severe nature of the inflicted wounds also depends on the heterogeneity of the tissue structure. Serious damage by 7H6 bullets was recorded at the final depth of the wound channel - more than 30 cm.

The mythical rumors about "entered the leg, exited through the head" are relatively explained by the curvature of the wound channel, which is noticeable in medical photos. Bullets with a displaced center of gravity leave entry and exit holes that do notcorresponding to each other. Deviations in the trajectory of 7H6 ammunition are fixed only at a tissue depth of 7 cm. The curvature of the trajectory is noticeable only with a long wound channel, while the damage inflicted remains minimal with edge hits.

A sharp change in the trajectory and principle of action of a bullet with a displaced center of gravity is theoretically possible when it hits the bone tangentially. Of course, if it hits a limb, the ammunition will definitely not come out through the head: it will not have enough energy for such a wound channel. The maximum penetration depth of a bullet when shooting at close range into ballistic gelatin does not exceed 50 cm.

About ricochets

Among military personnel with extensive experience in practical shooting, there is an opinion that bullets with a displaced center of gravity are prone to ricochets. In conversations, examples are often given of ricocheting off windowpanes, water, and branches when shooting at a sharp angle, or repeatedly reflecting a bullet off stone wall surfaces in enclosed spaces. In reality, the situation is somewhat different, and the shifted center of gravity does not play any role in this.

There is a common pattern for all ammunition: the minimum probability of ricochet in blunt heavy bullets. It is logical that ammunition 5, 45x39 does not belong to this category. When hit at an acute angle, at the same time, the momentum transmitted to the barrier can be so small that it is not enough to destroy it. Cases of lead shot ricocheting off water are not myths, despite the factthat the shot does not have any displaced center of gravity.

With regards to reflection from the walls of an enclosed space: indeed, M193 bullets are less susceptible to it, unlike the same 7H6 ammunition. However, this is achieved only due to the lower mechanical strength of American bullets. When they collide with an obstacle, they are significantly deformed, which leads to energy loss.

Conclusions

Based on the foregoing, several conclusions arise, and the main one is that bullets with a displaced center of gravity have indeed been adopted by many countries. What such ammunition is called depends on its modification and marking in specific states. They are not secret or forbidden. In Russia, they are represented by standard bullets of caliber 5, 45x39 of Soviet origin. All the myths and stories about rolling balls enclosed in their shells that change the center of gravity are nothing more than fiction and spectacular fairy tales.

To the dismay of many, the reason for the shift in the center of gravity closer to the tail of the bullet was an increase, not a decrease in flight stability. To be more precise, the shifted center of gravity is characteristic of all small-caliber pointed high-velocity bullets and is associated with their design.

As for the 7H6 cartridges, the shift of the center of gravity back really affected the trajectory of the bullet in the tissues of the body. When hit, a chaotic rotation of the bullet is recorded, followed by a deviation from the straight line of its trajectory as it deepens into the tissue. Likethe principle of bullets with a displaced center of gravity significantly increases the damage de alt when hitting living targets that are not equipped with armor.

However, one should not expect incredible miracles from bullets with a changed center of gravity like "entered the hand, exited through the heel": such stories are nothing more than fairy tales for the sake of a red word. In theory, such a result can only be a side effect of the use of high-speed small-caliber bullets with a high-strength jacket, but by no means a specially incorporated characteristic. Public opinion greatly overestimated the role of the displaced center of gravity in inflicting injuries of an atypical nature, unfairly attributing such merits to it. The same can be said about the increased ricochet: for the most part, it is typical for all small-caliber bullets. Cases of reflection from the surface of the water have been recorded with fine lead shot that does not have a changed center of gravity, so it is foolish to believe that ricochets are characteristic only for bullets with a changed center of gravity.

Unfortunately (or fortunately), but the trajectory and principle of bullets with a displaced center of gravity are strikingly different from those described in myths and legends, including those told by military personnel to increase the effect of stories related to ammunition and weapons.