HK XM29
| XM29 OICW | |
|---|---|
|
|
| general information | |
| Military designation: | XM29 |
| Developer / Manufacturer: | Heckler |
| Manufacturer country: | Germany |
| Weapon Category: | OICW |
| Furnishing | |
| Overall length: | 860 mm |
| Total height: | without magazine 209 mm |
| Total width: | over 50 mm |
| Weight: (unloaded) | FCS: ~ 2.06 kg HE: ~ 3.36 kg KE: ~ 2.0 kg Total: ~ 7.42 kg |
| Technical specifications | |
| Caliber : | 5.56 × 45 mm / 20 × 28 mm |
| Possible magazine fillings : | 6 grenades, 30 cartridges |
| Ammunition supply : |
Curve magazine / box magazine |
| Cadence : | 750 rounds / min |
| Fire types: | Single shot, 2 bursts of fire |
| Twist : | right |
| Visor : | 3/6-way ZF + IR + LEM |
| Closure : | Turret lock |
| Charging principle: | Gas pressure charger |
| Lists on the subject | |
The HK XM29 is a handgun developed by Heckler & Koch, ATK and Brashear LP as part of the Small Arms Master Plan (SAMP), which should have become the future orderly weapon of the US Army . Since the weapon system in the Small Arms Master Plan is referred to as Objective Individual Combat Weapon (OICW) , the XM29 is usually also referred to as OICW as a result of the OICW program. After the development of the HK XM29 was split up into three sub-projects, one of which has now been discontinued, the future is unclear.
history
As early as the late 1980s, the US armed forces came to the conclusion that the development of firearms with conventional projectiles , which derive their energy from the mass and the speed of the projectile, had reached its zenith. The new concept should therefore be based on air-igniting grenades as the main weapon , the effectiveness of which results from the explosion and the fragmentation effect of the projectile, and whose combat power does not decrease with distance. This also opens up other possibilities, such as fighting opponents behind cover or inside buildings. A combat range of 1000 m was required, as well as complete night combat capability, low weight, good ergonomics and the use of the latest computer technology and wireless data transmission, as well as the ability to fire both grenades and conventional ammunition.
Phase 1 of the study began in December 1994. An Advanced Technology Demonstrator (ATD) was to be built to test the feasibility of such a weapon concept. The weapon, then still known as the Selectable Assault Battle Rifle (SABR), was to be integrated into the Land Warrior system. Two company consortia were commissioned with the implementation, each given USD 95 million and 48 months to implement their concepts. Phase 2 began with the detailed system design and demonstration of subsystems, which was completed in February 1996 with the demonstration of critical technologies in ammunition, fire control and the weapon itself. Here the different approaches of the two groups of companies crystallized. In phase 3, which took place between January 1997 and 1998, both concepts were tested. Both weapons demonstrated the ability to attack targets up to 1000 meters away. The approaches of the participating company consortia were:
- ATK / HK / Brashear LP : Your weapon was larger and bulky, as it originally placed both barrels next to each other and did not use a bullpup design. The kinetic part had a rod magazine in front of the trigger, the 20 mm grenades were fired from a revolver drum next to it. The gun's ballistic computer had an integrated thermal imaging device with a controllable laser, and the intelligent image processing system marked the targets. The cylinder-cased grenades had a detonator in the center and two small steel warheads at the front and rear.
- AAI / FN / Raytheon : Your weapon was smaller and more compact and, with a curb weight of 5.45 kg, comparatively light. The kinetic part, an M4 , and the grenade weapon were in one housing, with the grenade weapon as a bullpup above and behind the assault rifle. The weapon’s ballistic computer did not have an integrated thermal imaging device for night combat - this had to be attached separately - but it also had a controllable laser, the intelligent image processing marked the targets. The 20 mm shells were powered by a high-pressure low-pressure system and fired from a recoil gun . The ignition unit was housed in the rear of the grenade, the front warhead was made of a tungsten alloy .
Both manufacturers, HK and FN, competed against each other at around the same time for the order for an Objective Personal Defense Weapon (OPDW) . The Joint Service Small Arms Program decided in April 1998 for the design by Heckler & Koch, Brashear and ATK, on the one hand because of the higher performance in terms of range and precision, and on the other hand because the design had an integrated thermal imaging device. ATK received $ 8.5 million to build seven prototypes and 4,700 rounds of 20mm ammunition to reach phases 4 and 5 of the project. On August 4, 2000, the group received an additional $ 6.946 million to begin pilot production. The weapon, now known as the XM29, was shown at the American Infantry School at Fort Benning in 2002 .
The weapon had changed a lot by then, and had become very similar to the model of FN, Raytheon and AAI. The original concept of using a drum magazine for the grenade weapon was dropped in late 1995, although a ready-to-fire model with a drum magazine was also made. After winning the tender in early 1998, the focus was on reducing weight, with the ballistics computer having to slim down and the barrels of the assault rifle and grenade weapon shortened.
Since ultimately the target weight of a maximum of 6.35 kg for a loaded weapon could not be achieved and the consumer expressed doubts about the effectiveness of the XM1018 grenade, the OICW program in 2004 was divided into three parts. OICW Increment I was supposed to introduce a modern assault rifle into the force ( HK XM8 ), and OICW Increment II was supposed to produce an airburst grenade launcher ( HK XM25 ). The two components should then be brought together as OICW Increment III, which will be referred to in perspective as an Integrated Air Burst Weapon . However, the integrated system will no longer appear in future financial planning.
technology
Ballistic computer
The ballistic computer, which was only referred to as the Target Acquisition / Fire Control System (TA / FCS) and was not given an XM number, was by far the most expensive component of the system. The aiming device, which is unique in the world for both the 20 mm grenades and the kinetic part, is equipped with a powerful computer processor . The system manufactured by Contraves Brashear Systems (now L-3 Communications ) has the ability to detect moving and still targets day and night. The integrated video and infrared camera sees moving targets and marks them with a rectangle that moves with the target. If the target stops, lies down or disappears, for example behind an obstacle, the rectangle will stop at the last known position.
There are various switchable viewing modes of the fire control computer that offer the soldier a red dot of variable brightness as a reticle . This point is also the normal target point of the built-in laser rangefinder . During the day, the targets are captured by a triple optical telescopic sight with an 11 ° viewing angle (DAY). This field of view is also available as a “fail safe” mode when the battery is empty, but without ballistics calculation and target recognition (OFF). The night vision channel (NIGHT) has all the possibilities of day vision, but provides an infrared image in the frequency range of 8-14 µm in order to make the heat radiation of people or other objects visible. The output of the video signal from the fire control computer can also be shown on the soldier's helmet display (TV). This allows the shooter to hold the rifle over (or near) cover, aim and fire without being hit. The MAG mode activates an internal CCD camera with 2x pixel zoom to increase the effective magnification to 6x. Four rotary switches , which are installed on the left side of the ballistic computer, allow the options of the weapon to be changed. From the front to the back:
- Channel: OFF, DAY, TV, NIGHT
- FUZE (grenade detonator): BURSTING, PD, PDD, WINDOW
- MAG (electronic 2x magnification): OFF, ON
- Brightness of the red point : BRIGHT, DIM
To calculate a fire control solution, the distance to the target is determined with a laser rangefinder, the beam of which can be swiveled by the computer. This is an erbium laser with a very thin beam that is emitted in a millisecond pulse. To do this, point the red dot in the middle of the sight at the target and press the yellow LEM button in front of the trigger shaft with the extended trigger finger. In order to compensate for the shooter's wobbling, the TA / FCS laser is swiveled exactly to the detected target and several laser pulses are emitted. An algorithm then estimates the true distance to the target based on a modal analysis . Another algorithm calculates and corrects the lead point in less than 100 milliseconds with the help of the distance of the target, the elevation and tilt angle of the weapon, the air temperature and humidity, the detonation mode and the trajectory of the grenades. After the calculation has been made, the lead point automatically moves to the correct position on the display in order to guarantee a high hit rate with the first shot when the shooter points it at the targeted target. The laser stays automatically aimed at the target and the distance is measured permanently, even if the target or the shooter moves. The compensated target point is calculated and displayed in real time. The system can track up to four targets at the same time, but only one of them can measure the distance. When the trigger is pulled, the TA / FCS transmits the necessary information to the 20 mm grenades.
The user can use buttons and switches to adapt the information that he gives and receives from the target computer to his needs. Three buttons for the index finger are located between the magazine slot and the trigger. The uppermost, yellow one activates the laser rangefinder, underneath there is a "+" and underneath a "-" button. These two buttons enable the shooter to change the distance measured by the laser rangefinder in 1 meter steps or to change settings in the "menu". The "Menu" button is located at the rear end of the target computer, on the lower left next to the shooter's eyepiece , to call up the computer menu and to make personal settings:
- TRACKER: Every possible target can be provided with an overlaid rectangle in the reticle
- RANGE DISPLAY: Distance data are displayed with or without manual changes in the reticle
- COMPASS DATA: Compass data (south = 180) are shown or hidden in the reticle
- AMMO SELECT: ammunition selection (TP; HEAB; HEDP)
Additional skills include self-diagnosis, zeroing in, and compass calibration . The Critical Design Review was completed in mid-2003. The uncooled infrared sensor with a pixel pitch of 25 µm and the other components could be combined into a highly integrated package that could meet both the weight and the running time specifications. The system weight including the lithium-ion accumulator could be reduced from about 2 kg to 1.2 kg. The runtime with one battery charge was over 15 hours. In addition, the range of the laser rangefinder could be increased to double the specification, to around 2000 m.
Kinetic part
The melee weapon is a compact assault rifle with a barrel length of 240 mm and a 30-round magazine for 5.56 × 45 mm NATO ammunition , which is mounted under the grenade weapon and is derived from the G36K . It is known as the "kinetic group" because it fires conventional ammunition and the bullet's effect is based solely on its kinetic energy (KE). This is a gas pressure charger with a rotating head lock with six locking lugs, which works as follows:
After the shot has been fired, the combustion gases are fed through a hole in the front center of the barrel into the gas outlet on the gas piston. The gas piston is connected to a drive rod which transmits a drive pulse to the bolt carrier. The bolt carrier then moves backwards and presses the bolt head's control bolt down via its control cam. This forces the bolt head to turn slightly so that the locking lugs are released and the bolt unlocks. The closure continues rearwardly and pulls the empty cartridge case by means of the extractor from the cartridge chamber of the barrel. The cartridge case is then ejected to the right by the ejector . The closure, which continues to return, tensions the closing spring and presses the hammer down into its latching position. After the rest of the return energy of the lock has been consumed by the lock buffer at the end of the return path, the movement is reversed. The recoil spring pushes the bolt carrier back into its starting position, with a new cartridge being fed from the magazine into the chamber through the advance . The bolt carrier turns the bolt head back into the locking position via its control bolt.
There is a button and two rotary switches above the handle. The front button is used to release the magazine, and the middle rotary switch to switch between HE and KE. The rearmost rotary switch enables the shooter to choose the fire mode: There are only two fire modes available for the KE part: Safe, single and two-shot burst . In the event of a total failure of the aiming device, the compact assault rifle can be used completely separately from the other modules for self-defense. However, it then no longer has a sighting device, so this is only intended as an emergency solution. The kinetic group is inserted from the front under the grenade weapon and fixed with a bolt .
Grenade weapon
The main weapon used is semi-automatically fired 20 × 28 mm grenades , which are fired from a 364 mm long titanium barrel. The system is a gas pressure charger with a rotary head lock, in which the gas is extracted directly at the muzzle, which is located inside the weapon. The gas is pressed there in the radial direction through a perforated sleeve, the holes of which are angled. As a result, it moves a short distance backwards and gives an impulse to the gas linkage, which is connected to the bolt carrier, in order to accelerate the bolt carrier backwards for unlocking. As part of the bolt carrier, there are two parallel springs above the bolt head. After the system has reached the rear end of the housing and the ejector has ejected the empty case, the springs push the bolt carrier and the perforated case forward, a new shell is loaded from the magazine into the chamber and the bolt is locked. The “mouth” that can be seen from the outside is only the front part of the gas trap, which still has its own short piece of pipe after the muzzle. A nut on the "muzzle" can be used to adjust the distance between this barrel and the barrel muzzle to regulate how much gas flows through the slot between barrel and barrel through the perforated sleeve. The nut was omitted in later versions for weight reasons.
The peculiarity of these grenades, classified as XM1018, is that the ignition unit with the batteries and electronics is located in the middle of the grenade. The grenade has small warheads at the front and rear, which are detonated by the electronics depending on the set explosion mode. If the grenade is supposed to explode in the air, the electronics count the rotations that the grenade makes to maintain its gyro stabilization . The grenade is fired when the necessary number of rotations has been made, which was programmed into the grenade by the TA / FCS prior to firing. The programming is carried out contact-free via induction coils. Six grenades are carried in a magazine. The grenade launcher , constructed in the Bullpup design, has a high muzzle velocity of 240 m / s, which results in a flat trajectory for the grenades and a range of up to 1000 m. If the grenades hit an obstacle within 50 m after being fired, a built-in barrier prevents detonation to protect the shooter. If the grenade was not destroyed after the shot, for example because the programmed distance could not be reached in bursting mode (e.g. wall in the way), it destroys itself after a while. The 20 × 28 mm grenades can open Four different explosion modes can be programmed, which can be selected with the FUZE rotary switch on the ballistic computer:
- Bursting : Exploding in mid-air at a target approximately 1.75 m above the ground.
- Point Detonation (PD) : Exploding when hitting a target.
- Point Detonation Delayed (PDD) : Penetration of a thin obstacle and an explosion 2–3 m behind it.
- Window (WIN) : Explode in the air 2-3 m behind the lasered distance.
In addition to the already developed and expensive HEAB grenades ("High Explosive Air Bursting", German: highly explosive, exploding in the air ), another type of grenade HEDP ("High Explosive Dual Purpose", German: highly explosive, Multipurpose ) thought, which should be cheaper and was intended against lightly armored targets in "Point Detonation" mode. In addition, funds were spent on developing non-lethal varieties of garnet. If the aiming device fails, the grenade weapon can still be used in "Point Detonation" mode, but without ballistics calculation.
Embedding
Exercises
The training of OICW shooters should be carried out with electronic simulators, computer-generated combat scenarios and rifle mockups with recoil. Existing shooting ranges should be included as much as possible in order to reduce costs. Both company consortia selected the Omega Training Group (OTGI) for this. The training and qualification scheme should look like this:
After an instruction in the classroom (theory and disassembly), the soldiers should put their hands on the weapon and familiarize themselves with it. After that, a training shooting on the simulator was planned, followed by a qualifying shooting on the simulator. If the qualification was not achieved, the shooter would have had to do another training shooting. After passing the simulator qualification, the soldier would have switched to the shooting range, where only training grenades (TP) would have been fired. Practice and qualification shooting should first be completed during the day, then at night. If one of the training or qualification units failed, the shooter would have returned to the simulator. If night shooting was also successfully mastered, the soldier would have qualified for a Combined Arms Live Fire Exercise (CALFEX) with the XM29 and should fire live grenades.
In the troop
In 2001 it was planned that a fireteam of four soldiers would carry two OICWs with them. The Fire Team Leader and the Rifleman would then have become XM29 shooters, the armament of the Automatic Rifleman ( M249 ) and the Grenadier (M16 + M203) would not have changed. The squad leader would also have been equipped with an M16 unchanged, whereby it can select different attachments and visors depending on the situation.
The HK XM29 should be integrated into the land warrior system , which is the American part of the NATO Soldier Modernization . Through the wiring with the combat suit, the weapon could have transmitted the video image of the TV mode to the small display that could be folded in front of the eye in order to be able to fight targets from cover. Through the cabling with the combat suit, the XM29 would have been able to access the power supply of the Land Warrior, which would have enabled the TA / FCS to operate for at least seven hours if the weapon’s own battery were at an end. The numbers refer to the Land Warrior System from 2001, with the energy supply at that time.
Web links
- Globalsecurity: Integrated Air Burst Weapon
- HKpro.com - information and pictures
- OICW on WaffenHQ.de
swell
- ↑ a b Global security: XM29
- ↑ Federation of American Scientists: Objective Individual Combat Weapon (OICW)
- ↑ a b sistemasdearmas: XM-29 - SABR
- ↑ AAI / JSSAP: Firestorm Objective Individual Combat Weapon (OICW) , February 18, 1998 ( Memento of December 10, 2006 in the Internet Archive ) (PDF; 1.8 MB)
- ↑ MODERN FIREARMS SERIES VOLUME 3
- ^ A b c d e Grant Moule, Susan Franciscus: OICW Fire Control System / Contraves Brashear Systems LP ; Pittsburgh, Pennsylvania ( Memento from October 14, 2004 in the Internet Archive ) (PDF; 372 kB)
- ↑ Eric Brindley; Jack Lillie; Peter Plocki; Robert T. Volz: Selection of the thermal imaging approach for the XM29 combat rifle fire control system , Proc. SPIE 5074, Infrared Technology and Applications XXIX, 380 (September 30, 2003)
- ↑ Eric Brindley; Jack Lillie; Pete Plocki; Robert Volz: Progress report on development of the fire control system for the XM29 combat rifle , Proc. SPIE 5406, Infrared Technology and Applications XXX, 391 (August 30, 2004)
- ↑ a b c Waffen HQ: OICW Objective Individual Combat Weapon
- ↑ a b Sam Whitfield, Rod Gerdes: Evolving Affordable Training Systems for OICW and Related Factors - Individual & Crew-Served Systems , August 14, 2001 (PDF; 849 kB)
- ↑ Objective Individual Combat Weapon (OICW) / Revolutionizing The Infantry Weapon - Enhancing the Capabilities of the 21st Century Infantryman ; August 14, 2001 (PDF; 981 kB)