Reducing recoil is the first big problem in design. As we all know, the 12.7 mm bullet was originally a large caliber machine bullet, and its gun body was launched on a tripod. Nowadays, it is more difficult than semi-automatic sniper rifle to achieve shoulder-to-shoulder launch in reducing recoil. Because the semi-automatic energy consumes all kinds of irreversible energy in the process of ammunition supply, the recoil energy is reduced. However, the direct recoil of a 12.7 mm bullet is close to 4, N. Without effective measures to reduce the recoil, the shooter can hardly bear it. In addition, the shoulder contact point and the barrel axis cannot be ensured to be in a straight line, and even if the shooter can bear it, the necessary shooting accuracy cannot be guaranteed. Therefore, AMR-2 creatively adopts three-stage recoil reduction measures to reduce recoil besides the commonly used high-efficiency muzzle brake.
Firstly, a unique barrel grading recoil system (patented technology) is designed. AMR-2 successfully solved the contradiction between barrel floating and accuracy by reasonably controlling barrel movement. Before the projectile left the muzzle (the internal ballistic time was about 2.3 milliseconds), the shooter's sensible recoil was strictly controlled in a very small range, which basically did not cause the deviation of barrel axis. However, when the barrel recoils, the projectile has been out of the middle trajectory (about 8 milliseconds), and the vibration of the barrel recoils minimizes the disturbance of the projectile's flight. The barrel recoil system ensures high shooting accuracy.
Secondly, the AMR-2 adopts a specially designed spring hydraulic buffer between the casing and the stock, which can reduce the recoil force more effectively under the condition of the same recoil impulse.
finally, AMR-2 shoulder rest casts the latest military cushioning rubber outside the metal insert, and carefully designs the shape to ensure that the shoulder contact surface is straight and maximize the area. The recoil force of AMR-2 is only 1/1 of that of 79 sniper rifle with hard plastic shoulder rest. Although this test result can't fully reflect the shooter's sensible recoil, this rubber shoulder rest undoubtedly plays a great role in reducing recoil.
reducing the recoil reduces the muzzle jump on the one hand, and reduces the shooter's fear on the other hand, which creates basic conditions for ensuring extremely high shooting accuracy. On this basis, AMR-2 also adopted a number of technical measures to improve the shooting accuracy. In order to ensure the AMR-2 has enough accuracy, the designer has done a lot of work on the design and manufacturing technology of the barrel, and adopted special rifling for the first time in China, which improved the flight stability of the bullet and improved the long-distance accuracy of the sniper rifle. Special barrel precision forging technology, laser strengthening technology and chrome plating technology are adopted to meet the special requirements of high-precision large-caliber high-precision sniper rifle for barrel.
At the same time, the designer adopted a firing mechanism with the pin moving in translation. When firing, only the pin collides with the primer along the barrel axis, and the time from releasing the pin to hitting the primer is short, which can be said to be the most beneficial form of all firing mechanisms to improve the firing accuracy. The launching mechanism adopts the transmitter of competitive sports firearms, and the trigger is pulled smoothly with a trigger force of 12~18N.
The overall layout and small structure of AMR-2 attach great importance to the rationality of ergonomics. The distance from the shoulder to the trigger and the size from the grip to the trigger are determined strictly according to the best size of the human body. The upper end of the case is designed with a picatinny rail. The optical sight can move back and forth on the guide rail, and the distance from the shooter's eyes to the eyepiece can be adjusted according to different needs.
It is particularly worth emphasizing that the cheek-sticking design of this gun is unique. First, although the cheek-sticking board is made of ultra-hard aluminum, its surface is sprayed with soft material, which will make the operator feel very comfortable when it comes into contact with human face, and the height of the cheek-sticking board can be adjusted at will by pressing the button. The designer also carefully designed the grip and processed fine anti-slip lines on the surface. The butt of the gun is equipped with a rear handle for the right hand to hold, which is very comfortable for the shooter to hold. This design fully embodies the people-oriented design idea, and the comfort of operation and aiming is of course self-evident for improving the accuracy of weapons.
based on the above design ideas, the shooting accuracy of AMR-2 has reached an unprecedented level. In its accuracy test, the R5 value of 1m is 1.8cm, which is even higher than the shooting accuracy of a standard bullet used in a ballistic gun. One target's R5 reaches an astonishing level of 1.1cm, which means it is very easy to play a table tennis at 1m with this gun. One of the major disadvantages of the 12.7mm caliber sniper rifle is that the muzzle noise, muzzle shock wave, muzzle smoke (flame) and other emission characteristics are obvious. In secret operations such as anti-terrorism special operations, the sniper's activities must be highly concealed to ensure the success of the operation and his own safety. If special technical measures are not taken, there will inevitably be such obvious launch characteristics as the dust flying when Barrett M82A1 is launched in the United States. Moreover, the powerful noise of large-caliber sniper rifle is close to 18 decibels (close to the level of artillery), so the shooter can't shoot without hearing protection devices such as earmuffs, but wearing earmuffs will definitely seriously affect the necessary communication and wireless communication between the shooter and his comrades. The muzzle flame of a 12.7 mm bullet is sprayed forward nearly 5 meters without muzzle device, which is not only easy to be exposed at night, but also may cause explosion in dangerous environment. It can be seen that the above launch characteristics must be reasonably solved to meet the applicability of the weapon in special occasions. To solve this problem, the muzzle pressure and airflow speed must be reduced. For this reason, the designer of AMR-2 specially designed a muffler with a number of patented technologies. The test results show that the muzzle noise can be reduced by more than 2 decibels by using this muffler, reaching the level of ordinary 7.62 mm bullets, that is to say, the sniper's battlefield survival ability can be greatly enhanced without wearing earmuffs when launching. Moreover, due to the reasonable design, the effective length of this muffler is only 2 cm, and the size of the whole gun is not excessively increased, and it can be quickly disassembled and assembled.