Over the years, there have been many options and different designs of silencers for the sound of small arms fire. Along with increasing the number of chambers and complicating their configuration, improving the design of silencers goes in many different ways.
Variants and designs of silencers and nozzles for silencing the sound of a shot for small arms.
The bulky silencer housing often closes conventional sights, so it is sometimes positioned eccentrically to the axis of the device well below the axis of the barrel. Using traditional structural schemes, many designs of silencers have been created, the schemes of which are given below.
a muffler (1) containing a central perforated or mesh tube (2), the perforations of which repeat the course of the rifling. The space between the casing and the tube is filled with sound-absorbing material (3). Noise reduction occurs during the dissipation of sound energy as compressed powder gases pass through a sound-absorbing material.
It is possible to use metal shavings to “stuff” the muffler, then the dissipation process will include the rapid absorption of heat of the powder gases by heat-intensive metal shavings.
Silencer Designs for Shots Containing Internal Partitions.
The figure below shows a silencer circuit, in the case of which there are installed partitions with central perforation (4), separated by free volumes. The noise level is reduced by reducing the speed and pressure of the powder gases during successive compressions and expansions when passing through a bullet of successive chambers. The second figure shows a silencer, in the housing of which there is a series of forward-reverse cones (6), forming expansion chambers.
A central tube and screw channels (7) are installed in the housing of the next muffler, and there is a profile divider at the outlet. In the next silencer, shells are installed sequentially one after another, close in shape to Laval nozzles. The following is the design of a silencer, which is a combination of structures with a tube and reflector half-toroid (9). One and a half tooids change the movement of gases to the opposite, which increases the efficiency of reducing their speed and pressure. Toroids can be replaced by elements of a different shape in the simplest case, flat membranes.
Silencer designs for shots using elastic deformable shutter elements.
The figures below show the designs of silencers for the sound of a shot using elastically deformable shutter elements. Rubber disks (10) are installed in the silencer case, having star-shaped notches in the center at an angle of 120 degrees relative to each other. Noise reduction is also achieved by quickly closing star-shaped openings behind a passing bullet and isolating expanding portions of powder gases in separate, relatively sealed gas cut-off chambers.
Designs of multi-chamber mufflers.
Siegfried Hübner from Karl Walter (Germany) developed a silencer design in 1970 based on the influence of the shape of the back and front walls of a large expansion chamber on the internal gas dynamics of the silencer body.
The decrease in the energy of powder gases occurs due to the repeated re-reflection of shock waves inside the silencer body and the damping of the shock wave by the oncoming wave. The know-how of this silencer is the knowledge of the gas-dynamic picture of the flow in the silencer body and the meticulous calculation of internal gas dynamics for a specific gun and cartridge. When replacing ammunition, the whole picture of internal gas flows changes, and the effectiveness of silencing the sound of a shot drops sharply.
Muzzle nozzle designs that soften the sound of a shot.
A variety of muzzle silencers are nozzles that soften the sound of a shot. The design shown in the figure below was patented by W. Jorell in 1959. From the muzzle end begins a channel having a length and diameter slightly larger than the diameter of the leading part of the bullet.
Through the gap between the bullet moving in the channel and the channel wall, the powder gases, overtaking the bullet, move forward and their pressure gradually decreases. Gases that break through the gap fall into the expansion chamber, in which their pressure continues to decrease and they are released through two vertical slots into the nozzle body.
The nozzle, invented by D. Holzer and manufactured by Taylor since 1975, consists of a conical socket connected to a barrel with a smaller diameter weapon and an external mixer pipe installed with a clearance relative to the socket.
The relative position and geometric dimensions of the pair of conical bell-shaped cylindrical pipes are selected in such a way that the pressure and velocity of the gases flowing from the bore, expanding and reflecting, are significantly reduced. Passing through the cone-bell and cylindrical nozzle, they work on the principle of a jet pump, draw air through the channels into the pipe, inside which they undergo strong mixing and cooling, leading to a decrease in the sound level of the shot.
Silencer designs of a shot using the movement and deformation of their constituent elements and components.
The muzzle silencers of the sound of the shot, which additionally use the movement and deformation of the structural elastic elements included in them and the movement of components, are not widely used. The figures below show a structural diagram of a silencer with deformation of elastic elements inside the housing. The dividers in this muffler are solid and separated by special springs. Deformation of the springs during firing provides additional energy dissipation.
Scheme of a silencer for the sound of a shot with the movement of elastic elements inside the body.
Operation diagram of a silencer with a valve.
The silencer contains a two-leaf valve in the pre-expansion chamber, operating on the principle of “tweezers”. Spring steel petals are fixed in a piston-cup with a small stroke along the muffler body. In the initial state, the piston-cup is displaced to the barrel, and the gap between the valve petals is sufficient for free passage of the bullet into the further expansion chambers.
When fired, the gases following the bullet push the piston-cup in the direction of the shot. The valve petals moving along the guide planes close and cut off the powder gases. In this case, the petals, like tweezers during capture, come together and are in a deformed, stressed state. As the pressure drops and the powder gases cool in the chamber, the petals straighten under the action of an elastic force, gradually releasing the gases into the gap formed. The piston glass returns to its original state. The silencer is ready for the next shot.
Original muzzle-mounted mechanical silencer invented in 1984 by a German engineer Jozef Rudolf Smatch.
The device of this silencer of the shot confirms the consideration that a decrease in the level of the gun sound can be achieved by longitudinally moving the silencer body relative to the inner part, which is fixedly mounted on the end of the barrel.
The scheme of the device and operation of the muffler.
Before the shot, the silencer is completely pulled over the barrel, which reduces the dimensions of the weapon with a silencer. During the shot, powder gases through the holes made in the fixed part act on the internal partitions of the outer casing, moving it forward. When the silencer body is in its frontmost position, it forms an expansion chamber where part of the powder gases is discharged, in which they expand, reduce temperature and are vented through a series of capillary holes.
After the gas pressure drops in the expansion chamber, the body returns to its original position under the action of return springs mounted on two guides located on the sides of the barrel. Having an original design, this shot silencer has some disadvantages:
1. During the shot, the length of the weapon changes and its balance is disturbed.
2. Automatic fire cannot be fired from a weapon, since the pause between shots is less than the silencer response time.
3. In the manufacture of moving parts requires high precision, which complicates the technology used.
4. The resulting carbon deposits can jam the moving parts, which necessitates a thorough cleaning of the silencer parts.
Although the efficiency potential inherent in the mechanical principle of jamming is significant, the engineering idea is original and promising. The main directions of improving the design of silencers are improving the efficiency of noise suppression (further attenuation of sound), reducing weight and size, increasing durability, improving accuracy and accuracy of fire, simplifying devices and manufacturing techniques, reducing costs.
Based on the book Devices for reducing the sound level of a shot for automatic weapons.
Konovalov N.A., Pilipenko O.V., Skorik A.D., Kvasha Yu.A., Kovalenko V.I..