Gas submachine gun HMS-710
The design of the submachine gun HMS-710 clearly says that one of the main objectives of this project was the elimination of illegal weapons alterations. Throughout stories gas weapons are handymen trying to modify it to use live ammunition. The use of traditional layouts and architectures borrowed in the firearms sphere in weapons greatly simplifies the illegal revision. The product is deprived of parts that exclude the use of certain ammunition, after which it can be used as a military weapon. Probably one of the main tasks of gunsmiths when creating a new automatic weapon was the exclusion of the possibility of reworking it for a combat cartridge.
The specific requirement for the "modernization potential" of weapons should not affect the solution of the main tasks. Because of this, an unusual arrangement of units appeared in the project, supplemented by a non-standard method of fire control. To solve the existing tasks while maintaining the required combat characteristics, it was decided to use a non-standard layout of weapons without the traditional design of the barrel chamber and ammunition supply systems. In addition, it was decided to abandon the mechanical means of ignition of the propellant charge. Due to the use of such ideas, the HMS-710 submachine gun was called a gas-electric weapon.
It should be noted that the classification of the product HMS-710 can be associated with some difficulties. From the point of view of the used ammunition and the possibility of choosing the mode of fire, it is a gas submachine gun. At the same time, the absence of mechanisms and automatics traditional for small arms, replaced by electronic systems, makes it possible to call the HMS-710 an electromechanical device for spraying irritants. In addition, the weapon is often referred to as an electric machine. Nevertheless, the development was initially positioned as a submachine gun, therefore in the future we will use just such terminology.
Externally, the new product was like some submachine guns of domestic and foreign development. The receiver was used with a front forearm and a pistol grip mounted in the center of its bottom. However, the appearance of the HMS-710 clearly indicated the presence of some differences from existing systems. So, it is easy to see that the dimensions and contours of the pistol grip did not allow to fit into her shop with ammunition. The dimensions of the rear of the weapon, as well as the controls placed there, also transparently hinted at a host of innovations.
The design of the submachine gun HMS-710 was divided into several main parts. To accommodate all units used lower unit receiver. A handle was attached to it from below, and rigid and hinged fastenings for other parts of the weapon were placed on top of it. The front half of the unit was given under the nodes responsible for the shooting. The fire control devices, in turn, were at the back of the weapon.
HMS-710 received the front casing of the receiver, in which the barrel was fixed relatively short length. In front of the casing there was a hinge for connection with the lower unit of the box, designed to perform the recharge. The rear part of the casing formed a rectangular volume, to the front wall of which the barrel breech joined. In the combat position, the casing was supposed to be in the lowered position, while its rear volume was lowered onto the magazine, forming a locked gas chamber. The barrel was attached to the front wall of the chamber. To keep the casing in place, a locking device of a specific design was used. With the rear block receiver was in contact with the protrusion rocking plate mounted on the casing on top. When the housing was locked, the plate could lie on its lid, and its narrowed end would enter the movable clamp.
The back of the receiver was a rectangular metal piece with stiffening ribs on the outer surface. Inside it was located part of the electrical equipment of the weapon. The plastic rear wall was designed to install controls and monitor the operation of systems.
Based on the requirements of the impossibility of alteration in military weapons, the authors of the project HMS-710 decided to locate the cartridges perpendicular to the axis of the barrel. Gas ammunition, in contrast to the bullet, while retaining their fighting qualities. The cartridges should be located in the store of the original design. Directly under the gas chamber front swinging casing was placed a rectangular plate with three longitudinal rows of holes, eight each. At the bottom of the cell to install the cartridge placed contacts of the electric igniter.
The use of electrical ignition has led to the need to use appropriate control systems. An electronics unit was placed in the back of the weapon, at the command of the shooter providing shot production. The main control for the electronics was a trigger placed in front of the pistol grip. In addition, the unit received several other controls and indicators located on the rear wall of the weapon.
They installed a light indicator of readiness for operation, a fuse switch, as well as a firing rate regulator. According to reports, by changing the speed of issuing pulses to the igniters, it was possible to achieve a rate of fire of up to 800 rounds per minute. Also on the submachine gun was present counter ammunition, with which the shooter could easily and quickly assess the remaining ammunition in stock.
As an energy source for electronic "automation", it was proposed to use a battery of the "Krona" type, issuing 9 V voltage. A battery compartment was used to place the battery. The battery compartment was covered with a removable lid. The battery was attached using a standard connector with two contacts, eliminating the possibility of connecting with non-compliance with polarity. The use of a non-standard magazine and a battery compartment in the handle made it possible to reduce the dimensions of the latter and to improve the ergonomics of the weapon as a whole.
The samples of the submachine gun HMS-710 that were demonstrated at various events had a relatively simple finish. The metal parts were black in color, the pistol grip received the lining, and a small plastic handguard was attached to the receiver in the front part of it. On the right side of the weapon there were several small surfaces for marking. It contained a serial number of several numbers, a mark on the caliber, the name and logo of the manufacturer, as well as the name of the model. It is interesting that in the surviving photographs all the inscriptions are in Latin letters: the weapon is designated as Iceberg GMC-710. Probably, foreign organizations were considered as potential buyers of weapons.
Hold weapons offered with the handle and forearm. Butt project was not provided. Despite the limited firing range associated with the type of ammunition used, the submachine gun still received sights. A fixed fly was placed on the front of the swing housing. Behind him, on the electronics unit, was the rear pillar of the design. Such aiming devices made it possible to provide guidance of the weapon with acceptable accuracy.

Rear wall with controls
According to some reports, for use with the product HMS-710 proposed so-called. powder cartridges developed by the Iceberg concern. Together with a powder charge, a certain amount of the active substance in powder form was placed in the sleeve of such a cartridge. A characteristic feature of the ammunition was the use of a primer, allegedly protected from firing by accidental impacts. In this case, an electrical pulse from the electronic control unit could lead to a guaranteed ignition. The cartridge sleeve of the cartridge was covered with a broken-through plastic cap-cap, preventing the contents from falling out and protecting it from external influences.
The original design of the weapon led to the formation of equally non-standard principles of operation and maintenance. Almost the only procedure for working with the HMS-710, borrowed from existing samples, was pulling the trigger.
To prepare the weapon for use, the shooter had to open the battery compartment cover on the lower surface of the pistol grip, connect the battery, insert it into the corresponding cavity and close the cover. Equipment store looked as follows. Having pushed the front latch, it was necessary to release the cage locking plate with the barrel. Turning the plate up and back allowed to “break” the weapon and turn the casing on a hinge. After that, access to the store plate was opened. Then, 24 gas cartridges of a compatible caliber 9 mm should be inserted into the cells of the magazine. Any additional devices to speed up the work with the store were not offered. It was necessary to equip it only by hand, one cartridge each. Having completed the placement of ammunition, the shooter had to return the casing with the barrel to the working position and fix it in its place with the help of a locking device.
The readiness of the weapon for firing was determined by the light indicator on the rear wall of the receiver. There was also a slide fuse switch. By moving it, the shooter could set the shooting mode and open fire. Pressing the trigger gave the command to electronics, which formed the impulse to ignite the cartridge cap in a particular cell. During the shooting, the automatics monitored the order of shooting cartridges in the cells of the store, preventing the simultaneous ignition of several charges and providing a consistent full shooting of the entire ammunition. For convenience, the arrow electronics unit was equipped with an indicator of ammunition. In a separate window on the back of the receiver, the number of remaining cartridges was displayed.
The vertical placement of cartridges led to the formation of the original method of hitting the target. When the weapon was in use, all the 24 cartridges were located in the cells of the magazine in a vertical position, perpendicular to the axis of the barrel. The supply of an electric pulse to the contacts of a separate cell led to the ignition of the charge of the capsule, which, in turn, set fire to the main propellant charge of the powder. The burning of gunpowder should have led to the sublimation of the powder charge of the irritant with the formation of a gas mixture consisting of the products of combustion of gunpowder and vapors of an irritating substance. Upon reaching a certain pressure, such a mixture broke the cork of the cartridge and went out into the gas chamber of the weapon. From there, the heated gases, which remain under great pressure, could only escape through the bore, heading towards the target.
After the existing ammunition was used up, it was necessary to open the weapon, remove the spent cartridges and put new ones in their place, preparing the submachine gun for new shooting. Replacing a “dead” battery was also not difficult.
According to the national press, published in the mid-nineties, the HMS-710 submachine gun could be bought by anyone in the future. For this, it was necessary to “carry out a standard set of formalities” corresponding to the acquisition of other gas weapons.

Weapons with an open gas chamber, the magazine and ammunition are visible
The unusual way of placing the cartridges made it possible to exclude the possibility of converting a weapon into a combat one. When a bullet cartridge was inserted into the magazine, an attempt at a shot could damage the structure of the weapon, but not damage the selected target. Modification of individual parts of the structure, used for illegal alterations, was useless, because in this case it was necessary to make too many changes. As a result, the proposed sample could be used exclusively for its intended purpose. The “modernization” of a criminal nature turned out to be unacceptably complex and meaningless.
An important advantage of the proposed design was the almost complete absence of moving parts. All operations for the production of a shot were carried out only at the expense of electrical impulses, which made it possible to significantly increase the life of the product in comparison with similar systems. This provided a solution to the tasks in the form of destruction of the target by an aerosol of an irritant substance. Due to the possibility of automatic shooting, the shooter could have made several shots in a row, creating the required concentration of irritant and compensating for errors.
Nevertheless, the HMS-710 project retained a specific disadvantage of its predecessor, which could lead to the abandonment of such weapons. The fact is that gas weapons do not imply the use of automatic firing. Such a fire regime is in most cases excessive and, moreover, in some situations it can be dangerous for the shooter himself. Several shots in a row can create an unacceptably large aerosol cloud that threatens not only the enemy, but also the shooter himself.
The project "gas-electric" submachine gun was created in the mid-nineties. Soon, samples of such weapons became exhibits of various exhibitions of weapons and special equipment. Custom design attracted the attention of specialists and the general public, but the case did not go further than admiring reviews. No one wanted to acquire a sample of weapons, distinguished by the extreme courage of the main ideas. In addition, according to some data, the further fate of the HMS-710 product was adversely affected by amendments to the law on weapons, which entered into force in 1998 year. New restrictions did not allow to rely on a wide range of buyers in the face of law enforcement agencies and private security organizations.
A promising gas submachine gun never reached practical use. At first, specific characteristics and capabilities, and then legislative restrictions, did not allow the original design to find its place in the arsenals. Like its predecessor HMS-700, developed on the basis of the OC-02 Cypress product, the HMS-710 product has remained in the form of a certain number of experimental and exhibition samples. By the end of the nineties, both of these developments disappeared from the expositions and catalogs of the Iceberg concern. However, developments in gas-electric weapons were not forgotten. Even before determining the final fate of the submachine gun, gunsmiths proposed a new means of protection, based on some ideas from the HMS-710 project. But now it was about the product in a different form factor.
Based on:
http://wartools.ru/
http://forum.guns.ru/
http://strangernn.livejournal.com/
Shunkov V.N. Gas and pneumatic weapons. - Minsk: Potpourri, 2004.
Alekseev I. The underwater part of Iceberg // Arms, 1997. No.3.
- Ryabov Kirill
- Shunkov V.N. "Gas and pneumatic weapons", Strangernn.livejournal.com
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