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"Indirect fire". Can't see, but shoot: fire from machine guns indirect fire when using an open sight
Material posted: Valetskiy OlegPublication date: 02-06-2013

Before the war a machine gun "Maxim" was shooting from the closed gun positions . This firing was conducted using a monocular gun sight and machine gun clinometer – quadrant, which for the machine-gun PC, largely occupied the niche of the "Maxim" does not exist.

The reason why after world War II refused to supply guns accessories, which allowed firing from concealed positions with machine guns, very simple. Practice has shown that the possibility to massively train the machine gunners shooting like this no. The use of instruments and necessary calculations are quite complex, often the educational level of soldiers simply did not allow their confidence to learn.

Despite the fact that the vast majority of tactical situations, the gun was used for direct fire, not much point to achieve the development machine gunners work with protractor-quadrant. In this article we will try to describe another method of firing indirect fire with a machine gun, using conventional open sight and simple methods of aiming the gun, whose development is not particularly difficult. Presumably, only such techniques may be of practical value.

However, before moving on to their presentation should answer the question why such shooting is generally needed. She's understandably less effective than a regular direct-fire. There are also mortars and automatic grenade launchers that can fire from closed firing positions. To use can push two factors: the use of the enemy long-range sniper rifles and especially high-precision weapons. The experience of recent wars, including the Anglo-Argentine war over the Falkland Islands and the recent US invasion of Iraq, the infantry ATGM uses not only to destroy armored vehicles, but also to fire at the enemy infantry. The feasibility of such use of ATGMs may be questioned, but the fact of such use remains a fact. Side, having an adequate supply of ATGM, will try to shoot from afar with impunity enemy emplacements from high-precision weapons.

Due to the growing spread and cheapening of such weapons, the likelihood of tactical necessity of firing of machine guns from concealed firing positions increases. The presence of mortars and automatic grenade launchers does not make it unnecessary, because in General, you should strive to defeat the opponent struck simultaneously from a larger number of possible firepower.

It should be noted that the closure height of only 30-35 cm, for example, the usual unevenness of the terrain, can make the position for the gun hidden from observation by the enemy from the front. A simple disguise, such as the cloak on the frame, or even associated "house" bunches of tall grass or branches of shrubs can make inconspicuous a position as from the observation helicopters, and unmanned aerial vehicles of the enemy, at least in the optical range. Using this method of shooting a great extent to retain the front slopes of the hills at the device of a defense on the reverse slopes.

Consider two situations when shooting from machine guns indirect fire: when there is the time required for zeroing, and when it is not.

Adjustment of milestones and benchmarks be produced as follows. First get hit by the bullets in the crest closing, determining, thus, the position of the gun, which does not allow bullets to fly through the closing. Then slightly lift up up the barrel of the gun and watch over the places of fall of the bullets on the other side of the closure, thereby determining a dead zone for closing the gun can't shoot through. Then the position of the gun is fixed. The methods of fixation will be discussed below.

Further the ranging of boundaries and landmarks located outside of the dead zone. After you get to put bullets in the area of landmark or milestone, the position of the gun is also recorded and marked (recorded).

Should indicate that fundamentally we think this method of adjustment, milestones and landmarks, when the sight of a gun does not change. In this case, the adjustment is achieved solely by experience, by raising and lowering the barrel of the gun. But this method should be avoided, as it does not allow you to enter any adjustments in the future. It should not be forgotten that the difference between the angle of aiming when shooting at the range at 100 meters and 1500 meters from the PC with a bullet with steel core (9,6 gr.) is just over 2 degrees. Therefore, to introduce any amendments "to the eye" is extremely difficult. Therefore, the body of the gun using a simple plumb-line or on-eyes set horizontally, and then make the adjustment by setting the scope for the distance to the turn or landmark. So if necessary you can enter the correction in range, using the sights.

In General, adjustment of milestones and targets when firing from the closed position similar to the rules of shooting when shooting in conditions of poor visibility (night, fog or artificial smoke) specified in the instruction on small business.

In order not to reinvent the wheel, to quote the governing documents.

"With early preparations for shooting ... in the parapet gutter is cut out so as to be laid on him ... (gun) pointing in the direction of turn of the probable appearance of the enemy". Fire training, M.: Voenizdat, 2009, p. 264

And "when early preparations for shooting... the position of the gun, fixed to a firing position using available tools. For this purpose, when shooting from the bipod with pegs limited to side movement of the skid legs bipod and butt. The position of the gun height is fixed a layer of turf (dense snow Board with cutouts, etc.), planted under the pistol grip. When firing from the machine... feet of the machine should be fixed with pegs. Then bring the gun to the crosshair, the corresponding distance milestones or benchmarks to prepare the fire, marked by clearly visible at night to the point of interference, to limit the dissipation on the front and record the installation." The manual on shooting business, Moscow, military publishing house, 1987, p. 491-492

The order of mark pickup with a machine gun, I think, to present here should not be. Indicate that the crosstalk point may be the crest of a closure or exhibited at some distance from the gun milestone. When using milestones should be set no closer than 15 meters to the gun so that the angular size of the milestones can be neglected. You can also use auxiliary firing at a point which is either in alignment with the goal or close to it and above target, for example, the top of the tree. When firing at such secondary point of aiming the machine gun can be installed near the crest of the closure. Then the machine gunner to lay down for the gun and lifted to about the height of the head above the gun. If the terrain ahead is not visible, so the machine gun flashes and pulsating wisps of smoke when firing it visible to the opponent will not. Guide to infantry soldier, Chapter 12 "Service heavy machine gun"

Instead of a layer of turf you can use the wooden tabs (a set of plates stacked on one another). These tabs are best kept near the peg marking the direction of fire, in the confusion of battle is not to confuse what peg tabs what are. When zeroing, prone, marked right and left end of the turn and the middle.

At each position, if more than one, are the same steps for the adjustment of boundaries and landmarks, then place the opener and butt accurately marked by pegs. mayor of Coconuts B. V. and major General Romanovsky D. I., "the Fighting troops in the smoke", M: Military publishing house people's Commissariat of defense, 1943, pp. 23-26
The second situation to be considered is shooting from the closed position without prior registration. Actually, the basic idea of this method is very simple. The observer who sees the goal behind the closure, sets milestone (milestones), which specifies the direction of the gun at the target. Then crawls to the side with the line gun-milestone (milestone)-the purpose and informs the gunner the distance to the target. If necessary, adjust the range, indicate how heavy you need to increase or decrease the scope. Adjustment in direction, as a rule, is not carried out, and the command of the fire by spreading on the front. When you transfer the fire to another target milestone (milestones) are swapped.

For security purposes, at the time of installation milestones the gun must be unloaded. Of course, this method has limitations in use. First of all, note that the maximum distance from the gunner to the observer, in which the latter actually able to adjust the fire is about 100 meters. To shout or to domchatsya hands at long range nearly impossible. Of course, if between the machine gunner and the gunner has laid the radio or field telephone (which, in General, can not count), this problem is removed. Also keep in mind that distance limits the visibility and conspicuity milestones. At least one of the milestones set in the vicinity of the crest of the closure. When you consider that in the General case as a milestone used a wooden stick, and not too thick, it should be understood that from a certain distance it can fuse to the gunner with the surrounding terrain. In addition, to maintain control unit for the removal of the heavies at large distances is unlikely to be appropriate.

Specified 100 meter distance resulted maximum height of the closure and firing ranges and as a consequence, the type of terrain where shooting from concealed positions without pre-zeroing can be used.

If we look, for example, to the table of above average trajectories above the line of aim for the machine gun, we see that at a distance of 100 meters, the average trajectory manages to rise above 30-35 centimeters (minimum height of mask that could hide a machine gun) only fire at a range greater than 500 meters. Given the fact that the most valid fire with machine gun is achieved at ranges up to 1000 meters, this means that the height of the closure can not exceed approximately 1.4 meters. At ranges of 600 meters height of closure shall be less than 50 cm, 700 meters – 70 cm, 800 meters – 90 cm, 900 meters – 1,10 see That is, shooting from concealed positions without pre-zeroing is possible only on flat open terrain. Moreover, the consumption of ammunition in this fire are of course higher, but the effectiveness of this fire - lower than when firing at distances up to 500 meters. Therefore, this method of firing tactically not very comfortable and really can be applied only when compelled to the circumstances.

Reference, here is the depth of the affected areas (may be determined by reference to the excess of average trajectories above the line of aim and dispersion). When shooting at 500, 600, 700 and 800 meters flatness of the trajectory provides an in-depth target zone. For example, when shooting at 700 meters (sight 7), exceeding the average trajectories are at range
500 m, 1.7 m, 600 m and 1.1 m, that is, for growth objectives 1.7 m. the whole distance of from 500 to 700 meters is included in the affected area. When shooting at 900 meters (sight 9) for growth goal of 1.7 M. the target space will be approximately from 825 m to 900 m, and when firing at 1000 meters (sight 10) smitten space will be approximately 940 meters to 1000 meters.

Defining the minimum (500m) and maximum (1000 m) a range for the firing of machine guns from concealed positions using conventional open sight, you can specify bispectrality way to determine whether the bullets to touch the crest of the closure. By choosing the sight on the target range, you should not changing the position of the gun in space to reduce the sight to the unit (as if reducing the range to 100 meters), if line of sight goes above the close, then the bullets hitting the crest of a closure will not be.

Now, on the order pickup gun at the target direction.

As mentioned above, it is made by milestone, set by the observer close to the crest of the closure. The problem is that one observer can't place a milestone on the gun in the closed position is the target, not allowing some kind of error so as to see both a goal and a gun, while between them is not possible. And when firing at ranges of 500 meters and above such mistakes lead to substantial penalties. So the second soldier is usually the gunner helps the observer to bring the gun on target. For this, he is at a greater distance from the crest of the closure than observer. He takes the position that it due to the closure saw the goal. Further distinguish two situations. If the gun is not tied to a specific point on the ground (trench or masking local subject, e.g., hive), machine gunner just stands up, or rather, stands up, or rises somewhat, on-line milestone set by the observer at the crest of the closing – aim. Establishes the second milestone (enough zaglubit it in the ground so the bullets don't cut it), and then transfers the gun to the place in the target two established milestones. If the gun is for tactical reasons it is undesirable to move, the gunner need to move away from the gun in the direction opposite to the direction of fire, to rise until, until he will see the purpose behind the closure, stand on the line gun-target, (you can put milestone in place of standing) and indicate to the observer located near the crest of the closure where he set a milestone. And the point of standing gunner, the machine gun, marker is at the crest of the closure and goal should be on one line. After that, the machine-gunner to lay down for the gun and firing in the direction established by the gunner at the crest of the closing milestones.

In principle, in tense moments of battle, the aiming direction can realize the soldiers are a few behind the light machine gun (soldier) is lifted to comb through the closure to see the purpose and results of shooting. This soldier tells the gunner how far clockwise or counterclockwise he needs to tighten the gun to point it at the target. But this method increases the danger of fire this way, as the enemy of the head of such a soldier is visible due to the closure.

Let us note that, given the range, it is necessary to amend the rear sight for correction for wind and to change the sight for adjustment for air temperature.

A few words about the tip on range. It should be understood that at ranges of 500 – 1000 meters to see the places of fall of the bullets is very difficult. The exception is cases where there are sighting-incendiary bullets, which give a bright flash when they hit the surface, but leave no visible mark to the enemy, like a tracer bullet.

In the General case, the observation is possible only if the bullet raise the dust (spray), when hitting the surface. Examples may be attack of leaf dirt road, dry land, shallow snow, brick walls, etc. Indirectly, information about a place of falling bullets can be obtained by the reaction of the opponent on fire. But in most common cases, when firing at a grassy field or on a fairly deep snow to see the places of fall of the bullets is extremely difficult. Tracer bullets, if the enemy is watching, we can't use because they will give the approximate location of the gun. Given that when shooting at ranges of 500 – 1000 meters you can use all six positions of the sight (5,6,7,8,9,10), and above on the affected area at these ranges, the shooting can be recommended to conduct "sweeps". First determined whether the target is closer to 500 meters or to 1000. In the first case, use the scope 7, in the second 8,9,10 (for each setting of the sight produced a long line and then change the setting).

Note also that the choice of scope should take into account the distance from the gun to the position of the observer, who sees what is behind the closure.

It is recommended that even with the training of shooting from the closed position, however, to equip the trench with a parapet, to be protected from enemy fire, carried along the crest of the closure.
Lieut.-Arendt brevete Colonel, Aide-memoire de l'officier de reserve d infanterie, Edition Delmas, Bordeaux, 1945, page 158-159.

In order to facilitate the adjustment of fire by the gunner, set a series of simple hand signals denoting numerals, as well as basic instructions of the observer to the gunner: "the sight of so many", "increase/decrease sight", "right", "left", "fire", "cease fire", "attention", "not see," etc.

In conclusion, we emphasize that the method of shooting is not always easy, but in certain circumstances may be unique. So know it does not hurt, but mastering them with not much difficulty and is a lot of study time does not take.

Andrey Markin



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