The appearance of this instance of weapons due to the fact that the means of individual armor have acquired not only the maximum distribution in the second half of the twentieth century, but also became relatively compact and light. Consequently, a weapon was required that could confidently hit an enemy protected by such personal protective equipment. It is natural that such results could not be achieved from one weapon and the main problem was to design a munition capable of fulfilling the goals set. The way out was the 9x39 cartridge, which was created on the basis of 7,62x39 for the silent samples of the Val machine gun and the Vintorez BCC rifle. Ammunition for a silent weapon with a heavy subsonic bullet showed excellent results in penetrating personal armor, however, had its own characteristics that could not but affect the characteristics of the future "armor-piercing" machine gun. A heavy bullet with an armor-piercing core coped well with 3 class body armor at distances of up to two hundred meters, but even for this distance it was necessary to make corrections, since due to the large weight and low speed of the bullet, the trajectory of its movement was far from ideal. Thus, it turned out that a weapon that had not yet been created was already known to be more difficult to use than samples for bullet cartridges faster and lighter, but they turned a blind eye to it, since maintaining effective fire from such an assault rifle was a matter of training and habit. Here are the armor-piercing qualities of the ammunition, at that time, were really very good.
Since the main characteristic of the weapon was “armor-piercing”, and even with the best patron such a parameter is limited primarily by the distance of use, it was decided to create not just an automatic capable of hitting the enemy on the means of individual armor, but also distinguished by its compact dimensions in this regard, it was more than enough and, in fact, it was necessary to choose the best of the existing solutions. Since the high armor-piercing properties of the bullet are limited to 200 meters, it was decided to design the weapon with the calculation of this maximum distance of fire. Naturally, this does not mean that the bullet flying 200 meters to stop and fall to the ground. As a result, the machine received a very short barrel, as well as a folding up butt. Subsequently, the weapon was upgraded, but more on that below.
As with all types of weapons with modest dimensions, the appearance of the Whirlwind is not the most formidable, but do not be deceived. Weapons are actually more serious than they might seem. Small dimensions and weight allow you to use the machine without delays from vehicles, in narrow rooms, if you forget about the rebounding ability of bullets and so on. The first version of the weapon, adopted under the designation CP-3 had a folding up butt, made by stamping. The butt itself was made so that even when folded, it did not interfere with the use of sighting devices, which consist of a front sight and reversible rear sight. If we talk about the elements of the control of weapons, then many note their almost perfect location and performance for a compact sample of the machine gun, but as many people have the opposite opinion. So the fuse switch is duplicated on both sides of the weapon and is represented by a relatively large lever, well accessible for switching even when the hands are protected by three-fingered mittens. The translator of fire modes is made by a separate, less noticeable element in the form of a transversely moving button, which is located behind the trigger under the fuse switch. Despite its small size, this control is quite convenient, although it does not stand out; many people may not notice it at all if you don’t poke a finger. A good solution was to replace the shutter knob with two slider bred forward, with which the shutter would be taken away by the shooter, but this was only a good solution in terms of size and wearing comfort. The cocking of the shutter, as practice shows, has become less convenient and longer, and this is not just a matter of habit, but reality as it is. The CP-3 version of the weapon was modest enough by modern standards, even a silent-firing device could not be installed on it, although the use of cartridges with subsonic bullet speeds could not be enough to include the PBS, even if it is not positioned as silent.
After being commissioned and a short run-in at the FSB, a task was prepared for the designers, which required making an armor-piercing "baby" a silent weapon with high accuracy without losing the original characteristics. In addition, there were recommendations for improving the ergonomics of weapons and processing some of the individual points. Roughly speaking, CP-3 was asked to do BCC and AU in one person, so CP-3M appeared. The appearance of the weapon has changed significantly. First of all, the butt is now striking the eye, which is now framed and retracts to the left side of the weapon. Since the weapon is relatively small, and the butt in the folded position began to overlap the forearm of the machine, an additional retention handle was also introduced into the design, which can be folded. In the convenience of holding a weapon when shooting, it turned out to be a gain, but with a folded butt it is still not convenient to hold the machine gun, it rests on the arm, but it is not inconvenient to mean. In addition, the weapon was able to install a silent shooting device, which was included in the machine gun. If you draw an analogy with a special machine "Val", then the updated "Whirlwind" with an installed device of silent shooting loses both in size and weight. This happens due to the fact that in a special machine “Val” the removal of powder gases begins even before the bullet leaves the barrel, through special openings in the barrel channel. In the Vortex machine gun, the barrel does not have these holes, respectively, and the silent-firing device is installed further, which increases the length of the weapon with CBE in comparison with the Val system. In addition, the upgraded machine guns changed their weight and dimensions when compared with the first weapon version. So the length of the machine with folded and unfolded butt was 410 and 675 millimeters, respectively, compared to 360 and 610 millimeters. The weight of the weapon has grown from two kilograms to 2,2 kilo. The length of the barrel remained unchanged, equal to 156 millimeters. The rate of fire equal to 900 per minute shots was also left unchanged, which is the case with small-sized weapons for a sufficiently powerful ammunition with an optimal rate of fire to ensure the best accuracy, not to shoot from trenches. A mount appeared on the left side of the weapon, which makes it possible to use the rifle with a telescopic sight, which increases the effective range of fire to 400 meters. Rather, it’s not the effective range that rises, but the opportunity to conduct aimed fire at a distance of up to 400 meters just appears, since the open aiming devices are designed for all the same 200 meters. Naturally, the third class of a bullet-proof vest at a distance of 400 meters a bullet already can and not "take". Also, weapons controls were reworked. Recycled completely. First of all it should be noted that the weapon got rid of the cocking knobs above the barrel, now it is one handle located on the right side of the receiver. The fuse switch has become larger; in its on position, it stands in the way of the bolt handle. Much more interesting is the translator of fire modes, which took place inside the safety guard just behind the trigger. How convenient this location is to judge is difficult. On the one hand, it seems as if the time for switching fire modes is significantly reduced, on the other hand, if hands are protected by thick gloves, switching can be difficult, even though the dimensions of the parts are rather large. It is difficult to say whether weapons of innovation have gone. On the one hand, the ability to install a silent shooting device and an optical sight is clearly a plus. On the other hand, the same butt and additional handle to hold the weapon are implemented in such a way that firing with the folded butt can only be rested against the same butt, which is clearly inconvenient unless you are left-handed. The changes made to the controls, although significant, can hardly be assessed as positive or negative. In the end, it is more a matter of habit and personal preferences, although the designers tried to reduce the time taken to shut the weapon and reduce body movements when switching fire modes, so, probably, the changes are still positive.
If we return to the question of the appearance of the machine gun, then many note that it looks like a weapon, as if it was collected from scrap materials. Looking at the "licked" foreign samples, it is difficult to disagree with this, indeed, the appearance is not the most ceremonial, but not the appearance at all determines the characteristics of the weapon.
The automatic works, despite the fact that it is a special weapon according to a fairly common automation scheme - removal of powder gases from the barrel. Much suspiciously similar in this model sample to the individual parts of a special machine "Val". So, for example, it can be noted that even the barrel is locked on the 6 stops. The trigger mechanism is similar to the AU, but if there is a well-functioning solution, then why not apply it. In general, the device is a usual and uninteresting weapon, so this item can be omitted.
If you emphasize the positive aspects of the weapon, then it is impossible not to note its flexibility. Since during the modernization, the designers had to make a weapon that combines the characteristics of the AS Val and the Vintorez BCC, we can assume that the Whirlwind is no longer a small-sized machine, but a separate rifle complex. Of course, it is impossible to reduce the performance of the VSS or to win the Val from a lesser noise during firing, but it can be used without CBE, which significantly reduces its dimensions. Thus, it can be noted that the weapon, even if it is considered without a silent firing device, turned out to be quite useful and necessary, complementing the silent BCC and AU samples.
In conclusion, I would like to separately note such a moment as the construction of this automaton to the absolute ideal by many people. So, quite often you can hear, and about this and similar samples, that they could become the main weapon in the army, because "they have no analogues". With the fact that a good weapon is difficult to disagree, but nevertheless it is special and cannot be used everywhere. The reason for this can be called at least the maximum distance of the effective fire, equal to 400 meters. Moreover, it is also necessary to take into account the fact that it is quite difficult to hit the enemy at such a distance from such a weapon. In other words, the weapon is suitable and good, but not for mass weapons.