RU2150063C1 - Firearm barrel - Google Patents

Abstract

FIELD: armaments, in particular, construction of barrels of rifled weapon. SUBSTANCE: the barrel has a smoothbore section near the cartridge chamber and a rifled cylindrical section. The rifling is made with a continuously varying angle, increasing to the muzzle end. The rifling angle near the muzzle end has a nominal value, and near the smoothbore section of the cartridge chamber it is less than the nominal value or brought to nought. The height of the rifling near the smoothbore section of the cartridge chamber is less than the nominal value. The pitch of rifling is permanent or variable. EFFECT: enhanced wear resistance of barrel, close grouping of fire and range of bullet flight. 4 cl, 1 dwg

Description

 The invention relates to the field of weapons, namely to the design and manufacturing technology of rifled weapons of various types, in particular to the design of trunks.

 As a rule, barrels of rifled weapons from a pistol to a gun have a fundamentally similar design. The barrel, which serves to direct the flight of a bullet or projectile, has a channel with several screw threads. Rifling serves to give the bullet or projectile directional rotational movement (see, for example, Manuals on small arms. 7.62-mm modernized Kalashnikov assault rifle (AKM and AKMS), Third Edition, M., Military Publishing House of the USSR Ministry of Defense, 1973, pg. 27-28). A bullet having a shell (made of various copper alloys with additives of steel, zinc, nickel) crashes into rifles when fired and receives a rotational movement. Since the initial speed of movement reaches 800 m / s and more, there is increased wear of the screw thread, and especially in the place where the bullet cuts into the screw thread. This determines the increased requirements for methods of processing the bore, its design, for measures aimed at reducing friction losses of a bullet on the surface of the bore.

 Typically, the threaded thread of the bore has a defined and constant angle of inclination to the axis of the bore or to its generatrix. Due to the fact that the bullet cannot receive rotational motion instantly, it crashes with its body into a threaded thread, is deformed, warps in the bore and at the same time some of the energy of the powder gases is lost, and the threaded protrusions at the beginning of the barrel are subject to increased wear.

 Known technical solutions aimed at eliminating these disadvantages. So, back in the 30s, a trunk was developed containing a cylindrical channel, including sections with different steepness of rifling (N. Nikiforov, Fundamentals of the artillery material part, M., Military Publishing House, 1936, pp. 98-99) . The disadvantage of this barrel is the expenditure of energy on the rotation of the projectile after reaching maximum pressure when passing the front section of the barrel.

 In patent RU 2084800 C1, cl. F 41 A 21/16, 07/20/97 the barrel contains a rear part having grooves made at an angle to the generatrix and providing linear or angular acceleration of the bullet, as well as the front part, which provides mainly linear acceleration of the bullet (or projectile) and is made with decreasing towards the muzzle section by the angle of inclination of the sections to the generatrix. The rifling of the front and rear of the trunk at the junction coincide. Such a device of the barrel channel reduces friction losses during the passage of the bullet through the barrel channel, however, the discreteness of the cut (on the threaded sections) and the subsequent decrease in the angle of inclination towards the muzzle cut contribute to the reduction of the angular acceleration of the bullet. As a result of this, the ballistic characteristics deteriorate, the accuracy of firing, and the range of the bullet fall.

 In the patent DE 4001130 A, cl. F 41 A 21/16, 07/18/91 An attempt was made to systematize the influence of a number of parameters of the barrel bore cutting on the magnitude of the force on the leading belt, which is valid when firing a shot. The barrel is characterized by a steepness of cutting, a variable angle of cutting, which provide a given force at a given mass of the projectile, its speed and gas pressure characteristic. It is shown that the maximum effort of the leading belt in comparison with the corresponding barrel with the usual cutting of constant slope is reduced by at least 25%.

 Nevertheless, it can be seen from the graphs that there are peaks in the force-path diagram in the bore, which leads to uneven wear of the cuts in different sections of the bore, which impairs the passage of the bore by the bullet.

 The closest technical solution adopted as a prototype to the invention is a barrel of a firearm containing a smooth part near the chamber and a cylindrical channel having a cut with decreasing pitch and increasing cutting angle in the direction from the smooth part to the muzzle. This barrel is described in US Pat. No. 5,765,303 A, class. F 41 A 21 / 00.16.06.98.

 In this barrel, the threaded part is divided into sections having a different pitch and angle of the threaded thread, and transitions from one thread parameter to another occur spasmodically from section to section. As a result of this, there is a sharp change in effort at the boundaries of the sites, which negatively affects the change in the acceleration of the bullet, both translational and angular, affecting the speed of departure and rotation of the bullet upon departure from the barrel. In this case, part of the energy of the powder gases is lost, and the threaded protrusions, especially at the beginning of the barrel, are subject to increased wear.

 The invention solves a technical problem aimed at eliminating these shortcomings - reducing energy losses of powder gases, reducing wear of the threaded portion of the barrel and, as a result, increasing the accuracy of fire, the range of the bullet without reducing the lethal force.

 This problem is solved due to the fact that in the barrel of a firearm containing a smooth part at the chamber and a cylindrical channel having a cut with an increasing angle in the direction from the smooth part to the muzzle of the barrel, the cutting is performed with a continuously changing angle, reaching a nominal value at the muzzle while the smooth part of the chamber has a cutting angle less than the nominal value or nullified.

 In addition, the cutting step is performed constant or variable. The cutting height of the smooth part of the chamber is less than the nominal value.

 The invention is illustrated in the drawing, which shows the barrel 1 of a firearm. In the breech of the barrel 1 there is a chamber 2 with a smooth part (bullet entrance) 3. In the channel 4 of the barrel 1 there is a threaded thread 5, which is made with a varying angle α. Change of this parameter occurs continuously (monotonously). In the direction from the smooth part 3 of the chamber 2 to the muzzle 6 of the barrel 1, the angle α of the cut increases. At muzzle end 6, this parameter reaches the nominal value. In the chamber (its smooth part 3), the cutting angle of the threaded protrusions relative to the axis of the barrel 1 decreases or disappears. The cutting height from the chamber 2, where it disappears, increases at the muzzle end 6 to the nominal value. The cutting step is performed constant or variable.

 The threaded protrusions are cut on a broaching machine with programmed control, where the linear movement of the tool relative to the barrel along its axis and the rotational movement of the tool relative to the barrel around its axis are coordinated accordingly using the programmed control system for the actuators of the machine.

 When fired under the pressure of powder gases, the bullet, receiving acceleration, begins translational movement along the barrel and at the same time rotational movement, entering the threaded part of the barrel. Moreover, since the angle α of its cutting continuously increases, and the cutting height also increases continuously, for the smooth part of the chamber it is less than the nominal value, the bullet is cut into the threaded thread gradually, without breaks and jumps, and therefore the deformation and warping of the bullet in the channel is practically eliminated 4 trunks 1.

 At the same time, energy losses of powder gases are significantly reduced, and the wear resistance of the bore is increased. In addition, obturation is improved, which eliminates unwanted gas breakthroughs. As a result, the accuracy of firing increases, the initial rate of fire when exiting the barrel and the range of the bullet increase.

Claims (4)

 1. The barrel of a firearm containing a smooth part at the chamber and a cylindrical channel having a cut with an increasing angle in the direction from the smooth part to the muzzle, characterized in that the cutting is performed with a continuous increase in the angle, reaching the nominal value at the muzzle and the smooth part of the chamber cutting angle is less than the nominal value or nullified.  2. The barrel of a firearm according to claim 1, characterized in that the cutting step is made constant.  3. The barrel of a firearm according to claim 1, characterized in that the cutting step is made variable.  4. The barrel of a firearm according to any one of claims 1 to 3, characterized in that the cutting height of the smooth part of the chamber is less than the nominal value.