Barrett XM109
| Barrett XM109 | |
|---|---|
|
|
| general information | |
| Military designation: | XM109 |
| Developer / Manufacturer: | Barrett Firearms Manufacturing . |
| Manufacturer country: |
 United States
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| Weapon Category: | Anti-materiel rifle |
| Furnishing | |
| Overall length: | 1168 mm |
| Weight: (unloaded) | 15.1 kg |
| Barrel length : | 447 mm |
| Technical specifications | |
| Caliber : | 25 × 59 mm |
| Possible magazine fillings : | 5 cartridges |
| Fire types: | Semi-automatic |
| Visor : | ASWFCS / BORS |
| Closure : | Turret lock |
| Charging principle: | Recoil loader |
| Lists on the subject | |
The Barrett XM109 is a sniper rifle developed under the Small Arms Master Plan (SAMP) to replace the M82 beret and derivatives in the US Army . Since the weapon system in the Objective Individual Combat Weapon as Objective Sniper Weapon (OSW) ( German "objective sniper weapon") is performed, the XM109 is commonly referred to as OSW. Since 2006, the weapon has been known as the Anti-Materiel Payload Rifle ( German "Anti-Wehrmaterial-Nutzlastgewehr"). The weapon with a rudimentary ballistic computer reached series production in 2004, but was not procured.
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.
The Objective Sniper Weapon defined in the Small Arms Master Plan was initially open to technology, only certain performance parameters were required. In the technology assessment phase, which ran until 1997, however, requirements were made that could not be achieved: For example, the following requirements were made in 1993 and 1994 in the Sniper Conferences of the Joint Service Small Arms Program (JSSAP): A hit rate of 100% at a combat distance of 1200 m against everything, against people at least 1500 m (whereby 2000 m was desired) also 100%. At the same time, the weapon should be able to be used against defense material, protected persons , persons in cover, vehicles and communication facilities. The weight requirements of the JSSAP of a maximum of 6.75 kg (4.5 kg desired) for the weapon were also unrealistic. However, these parameters were retained in the OSW technology demonstration program, which ran from 1997 to 2002.
After the experience of the Second Gulf War , US special forces demanded an anti-material weapon in caliber 20-25 mm. In 1992 the need was officially determined and on March 16, 1994 the requirements for this weapon were specified. The Joint Service Small Arms Program (JSSAP) then carried out fire tests in 2002 with the 25mm prototype of the Objective Sniper Weapon, which was compared to a Barrett M82 . The objective was to neutralize the 64N6 Big Bird radar of an S-300 anti-aircraft missile complex and a BMP-3 at a range of up to 800 m. The OSW performed better, especially over long distances, only about half the amount of ammunition was used.
In early 2004, Barrett Firearms Manufacturing, Inc was commissioned to improve the weapon’s performance and recoil, and to build 10 improved prototypes. These were delivered to the Army in August 2004. The Barrett Optical Ranging System (BORS) developed for the rifle was ready for series production about 90 days later, together with the rifle. Within the next six months, the weapon was to be further developed in order to be able to fire air-igniting ammunition . Likewise, all types of ammunition in the 25 × 59 mm caliber should later be able to be fired.
In 2006, the gun was waved along with the Barrett M107 and Barrett XM500 as an anti-materiel payload rifle by the United States Congress, but there was no procurement. The program was never officially discontinued. However, the weapon would be the sole user of the 25mm ammunition after the General Dynamics XM307 was also discontinued.
overview
The task of snipers is to fight enemy high-value targets (people or defense material) at a great distance with targeted shots. The direct support of own units, however, is less common and is usually perceived by group snipers. When arming a sniper, a compromise is necessary: Since shots at personal targets require high precision, locking systems are preferred that remain rigid when firing. So the weapons of choice are repeater . When shooting at material targets, on the other hand, a high destructive power and thus a large caliber is preferred. The strong recoil makes weapons with movable breeches and barrels desirable to dampen the recoil. Rifles like the McMillan Tac-50 or the PGM Hécate II try to combine high precision against personal targets with high destructiveness against material targets.
By firing air-igniting ammunition , the Objective Sniper Weapon (OSW) should have a better effect against both human and material targets: The air-igniting ammunition increases the hit rate against human targets at great distances, and it can also be used to fight opponents while taking cover. There is no need to shoot with pinpoint accuracy, it is enough for the grenade to explode near the enemy to put him out of action. At the same time, the larger caliber of the grenades increases the weapon’s destructive power against defense material. Anti-materiel weapons such as NTW-20 or RT-20 already exist today , which fire automatic cannon ammunition in caliber 20 mm with a muzzle velocity of 720 or 850 m / s. The OSW's 25 mm ammunition, on the other hand, only achieves half the muzzle velocity, which is irrelevant for the effect on the target, but reduces the weight of the weapon and recoil. The tasks of an anti-material and anti-personnel rifle could thus be combined in one weapon.
technology
construction
The weapon is based on the Barrett M107 and is identical to it except for the caliber used . Both systems are 70% identical and can be converted to the other version, similar to the XM307 and XM312 . The housing made of stamped sheet steel houses the repeating mechanism of the sniper rifle designed as a recoil loader . After pulling the trigger, the striking piece that shoots forwards ignites the 25 × 59 mm shell, the shell of which then leaves the 447 mm barrel at around 425 m / s. After the shot, the slide and barrel move back together, while the bolt head rotates and unlocks the weapon. When the barrel is unlocked, it moves forward again while the slide continues to retract, ejecting the case and finally loading the next cartridge. The hammer is cocked by the breech as it moves forward. The recoil of the grenade is dampened by the movable repeating mechanism, but a large part is taken over by the effective muzzle brake. The ammunition is fed via a five-shot box magazine . The total weight of the weapon with magazine is 15.9 kg.
The accuracy of the weapon was less important because of the shell ammunition. In the comparison shooting in 2002 between the M107 with Raufoss Mk 211 ammunition and the XM109, the M107 achieved a precision of 2.3 MoA at 600 m, while the XM109 achieved 2.53 MoA with XM1050 TP ammunition. At 800 m the difference was more pronounced at 2.74 to 3.33 MoA. This corresponds to a deviation of 80 cm at 800 m. The system precision with XM1050 practice ammunition is 1.1 mils at 1350 m, which corresponds to a deviation of about 50 cm.
Ballistic computer
The difficulty with sniper shooting is to make the best possible use of the system precision of the weapon, as this is reduced by external influences. During the OSW technology demonstration phase, the technical requirements for an Advanced Sniper Weapon Fire Control System (ASWFCS) were laid down in 1999 . A sniper rifle in .338 Lapua Magnum caliber was adopted as a surrogate for the Objective Sniper Weapon . Based on this, the relevant parameters for a precise shot were determined, as well as the necessary capabilities of the ballistics computer. However, it is unclear whether the Advanced Sniper Weapon Fire Control System was intended for the OSW only, or for any suitable weapon.
The system should consist of a spotting scope with a laser range finder , cross wind sensor and (conceptually) 20x magnification for the observer. The data should be sent to the gunner's ballistic computer, which, together with the air temperature and density, calculates the gun's lead point in real time. The position of the reticle in the rifle scope should be determined by inertial reticle technology (IRT) . For this purpose, sensors should record the weapon movements and calculate a corrected hit point in real time. While the gunner of a battle tank aims with the help of a rigid reticle and the weapon system is movable relative to it, the process is reversed with inertial reticle technology : the weapon is "rigid", i.e. cannot be influenced by the computer, but the reticle is movable. The marking in the telescope image therefore always points to the point where the bullet would hit if the trigger were pulled at that moment. To hit the target, the shooter must match the lead point and hit point. The (conceptual) enlargement of the weapon sight is given as 10x or 30x.
Ultimately, however, only the Barrett Optical Ranging System (BORS) was developed for the weapon in order to be able to perform anti-material tasks: This consists of a small device that can be mounted on a telescopic sight and with the help of temperature, pressure, distance and bullet type calculates the elevation angle of the weapon. To determine the distance, the shooter must manually enter the target height and hold the crossbar of the crosshair under the target. After pressing a button, the elevation angle on the BORS is adjusted until the crossbar is above the target and the button is pressed again. The distance is now calculated and the crosshair can be adjusted accordingly.
Web links
Individual evidence
- ↑ COMMERCE BUSINESS DAILY ISSUE OF FEBRUARY 7, 1996 PSA # 1526 US Army ARDEC, AMSTA-AR-PCW-D, Bldg 10, Picatinny Arsenal, New Jersey 07806-5000
- ↑ 1998 Army Science and Technology Master Plan ( Memento from May 2, 2013 in the Internet Archive )
- ↑ a b c globalsecurity: XM109 Anti-Materiel Payload Rifle
- ↑ BARRETT: XM109 BRIEFING UPDATE , May 11, 2004 ( memento of July 19, 2013 in the Internet Archive )
- ↑ a b RAND / Scott Hiromoto: Fundamental Capability Portfolio Management: A Study of Developing Systems with Implications for Army Research and Development Strategy , 2013 (PDF; 4.4 MB)
- ↑ a b 50TH ANNUAL NDIA SMALL ARMS SYMPOSIUM AND EXHIBITION: 25mm Anti-Material Payload Rifle (AMPR-XM109) , 2004 ( Memento from November 28, 2012 in the Internet Archive )
- ↑ a b ARDEC: Safety Test of the XM109 Rifle , 2005 ( Memento from October 13, 2012 in the Internet Archive ) (PDF; 413 kB)
- ↑ Williams, Anthony G. (2008) Defense Management Journal , Issue 41 ( Memento from October 25, 2012 in the Internet Archive )
- ↑ a b c ARL: Sniper Weapon Fire Control Error Budget Analysis , August 1999 (PDF; 5.6 MB)
- Jump up ↑ ARL: The Inertial Reticle Technology (IRT) Applied to an M16A2 Rifle Firing From a Fast Attack Vehicle , April 2000
- ↑ Barrett: Optical Ranging System (BORS) Operator's Manual ( Memento from April 2, 2013 in the Internet Archive ) (PDF; 2.2 MB)