A shot is the throwing of a bullet from the barrel of a gun barrel. Shot Shot

What is a shot? This phenomenon occurs when shooting, for example, from gunshot, cold or other weapons. It comes from the word "arrow". The shot is a complex complex of chemical and physical phenomena. Knowledge of the processes occurring during this action, and the influence of an impressive number of external causes on them, facilitates the Gunners in calculating the data to calculate the correct settings necessary for firing, and ultimately helps the successful execution of the tasks facing the artillerymen.

Phenomenon

It is known that a shot is a process of rapid transformation of the chemical power of gunpowder first into thermal, and then into the kinetic energy of the movement of weapons. This event can be conditionally divided into two phases: the movement of the projectile in the canal cannon and the complex of events that occur after the bullet is fired from the muzzle.

The bullet (shell) from the barrel flies out as a result of the operation of the powder gases. This phenomenon is determined by such qualities:

• High temperature of gaseous gases (2500-2500 ° C);
• An impressive magnitude of the pressure of gases (2-3 thousand and more atmospheres);
• Burning of powder charge in a rapidly modifying volume.

Process

How does a pistol shot happen? For its production you need:

• In the chamber to send the cartridge;
• Lock the barrel channel securely with a bolt;
• Pull the trigger.

At the same time, the following actions are committed:

• The drummer, under the influence of the shock-trigger mechanism, strikes a striking blow at the cartridge shell;
• The impact of the nipple is ignited;
• Through the bare beam, the beam of fire penetrates into the middle of the cartridge case and ignites the powder charge;
• The volume of gases that appear appears to increase and the pressure rises;
• Gases expand and press on shell shell and bullet;
• Gases press the bottom of the sleeve to the cup of the bolt, its walls to the walls of the chamber, and the bullet is forced to crash into the barrel cuts, move along its canal and fly forward.

These phenomena consist of four periods, which we will discuss later.

First step

You probably already understood that the shot is a very confusing process. So, consider the first stage of this phenomenon, which is called preliminary. Here, the powder charge is burned in an unchanged volume up to the format needed for the finished insertion of the bullet into the rifling. This phase is determined by the generation of the boost pressure. For small arms it is equal to 250-55 kg / cm².

Main Stage

The main period (the second stage) is characterized by the combustion of the powder charge in a rapidly modifying volume. It lasts from the beginning of the appearance of the pressure of forcing, to the absolute burnout of gunpowder. At this stage, the pressure of the gases reaches the highest level. For small arms it is equal to 2500-4000 kg / cm².

This pressure significantly speeds up the movement of the bullet in the canal, and as a result, the bullet space increases. In this regard, contrary to the influx of gases, the pressure begins to decrease, reaching at the end of combustion of gunpowder about 2/3 of the ultimate pressure. By the end of the period, the bullet moves at a speed of about ¾ of the initial.

The third period

Of course, a shot is a movement. What is the third period? After the combustion of the powder, new gases are discontinued. But since they have an impressive supply of energy, they continue to expand and, as a result, the velocity of the bullet increases.

This stage continues from the completion of the burning of gunpowder until the appearance of a bullet from the barrel channel. At the end of the phase, the pressure decreases rapidly and at the muzzle reaches 300-900 kg / cm2.

Some types of small arms, especially short-barreled (Makarov's pistol), do not have a third period, since by the time of departure the bullet from the barrel canal of complete combustion of the powder gas practically does not occur.

Fourth stage

How can we characterize the fourth stage, or the period of the results of the activity of gases? At this time, the gases emanating from the barrel after the bullet continue to act on it. This phase lasts from the moment of the appearance of the bullet from the barrel channel to the moment of the completion of the influence of gaseous gases on it.

At this stage, the pressure is sharply reduced, and the speed of the bullet gradually increases until the pressure acting on it is equal to the air resistance. The bullet flies at maximum speed, which is reached at a distance of a couple of dozen centimeters from the barrel. It should be noted that the shot from the gun occurs in an identical manner.

Explosives

What are explosives ? These are chemical and unstable mixtures that can be instantly converted into gas under the influence of insignificant external nivations (shock, heating, injection, etc.).

How does the sound of a shot appear? An explosion is a very rapid chemical or physical change in a substance that accompanies the same rapid transformation of its latent (potential) energy into mechanical action. It is produced by evolved gases, striving for expansion. Thus, gases create an increased pressure in the environment surrounding the explosion zone. The accompanying sign of this action is a powerful sound.

The chemical reaction, which results in an explosion, is called explosive transformation. Rapid combustion of explosives refers to the process of explosive change, distributed throughout the weight of explosives at a speed of not more than a couple of meters per second. If this action takes place in an open space, it usually accompanies some effect.

In a closed vessel, the explosive is burned more vigorously, and the process is accompanied by a piercing sound. A classic example of such an explosive transformation is the incineration of the smokeless powder gunpowder in the barrel (speed about 10 m / s). Combustion is accompanied by a rapid build-up of pressure in the stem channel, which is distributed in the direction of the smallest resistance, pushing out a bullet or projectile from it.

Silencing

Sometimes it is necessary that the sound of the shot is not heard. There is a principle of sound attenuation in pneumatic and firearms. This is the so-called cutoff of the shot gases, based on the overlapping of the barrel or the dummy of the cartridge case with a special plug moving along the stem channel or the immanent surface of the sleeve after the bullet (projectile).

In the case of firearms, the term "cutoff of shot powder gases" is also used. After the projectile flew out of the barrel or left the sleeve, the stopper stops in a special narrowing of the barrel or narrowing of the collar of the cartridge case. As a result, it locks the powder or other gas throwing the projectile in the sleeve or trunk under residual pressure.

Since the gases do not escape into the atmosphere and do not expand in it, the sound of the volley is virtually absent. Cutoff of firing gases is effective only when the velocity of the emitted bullet is less than the speed of sound in the atmosphere.

Bow

And what is a bow shot? This throwing weapon, designed for firing arrows. In order to make a shot, the archer pulls the bowstring, by which it stores energy in the bent arc of the weapon, and then releases it. Further, the arc, swiftly unbending, transforms the reserve potential energy into a kinetic energy, which affects the flight of the boom.

The range and speed of the shot depends on the tension of the string, the design of the gun and the weather. Bows are divided into compound and simple, but they all represent an arc with a string for throwing arrows. Simple were created from a single piece of wood up to 1.5 m in length. Compound bows were shorter and made from different materials - wood, horns, animal tendons. It is known that with the reduction of the length of the arrow, the necessary power, flexibility and elasticity are achieved.

The bowstring was made from animal veins, rawhide, intestines or plant fibers. Many people like to listen to the sound of stretching bowstring bow, followed by a piercing whistle of a flying arrow: it is very beautiful and fascinating.