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Remington Model 870 (Shoutgun)
| Remington 870 | |
|---|---|
 Remington 870 Marine Magnum | |
| Type | Shotgun |
| Place of origin |  United States |
| Service history | |
| Used by | See Users |
| Production history | |
| Designer | L.Ray Crittendon, Phillip Haskell, Ellis Hailston, G.E. Pinckney |
| Designed | 1951 |
| Manufacturer | Remington Arms |
| Produced | 1951-present [1] |
| Number built | 10,000,000+ [2] |
| Variants | Wingmaster, Express, Marine, SPS, SPS-T, XCS, TAC, Super Mag,MCS |
| Specifications | |
| Weight | 7.0 lb (3.2 kg) to 8.0 lb (3.6 kg) |
| Length | 37.25 in (946 mm) to 50.5 in (1,280 mm) |
| Barrel length | 18 in (460 mm) to 30 in (760 mm) |
| | |
| Cartridge | 12 gauge, 16 gauge, 20 gauge, 28 gauge, or .410 bore |
| Action | Pump-action |
| Feed system | 3- to 8-round internal tube magazine |
| Sights | Bead, twin bead, adjustable open sights, or ghost ring (all iron sights). Also cantilever and receiver-mounts for scopes [3] |
The Remington Model 870 is a U.S.-made pump-action shotgun manufactured by Remington Arms Company, Inc. It is widely used by the public for sport shooting, hunting, and self-defense. It is also commonly used by law enforcement and military organizations worldwide.
Development
The Remington 870 was the fourth major design in a series of Remington pump shotguns. John Pedersen designed the fragile Remington Model 10 (and later the improved Remington Model 29). Working with John Browning, Pedersen also helped design the Model 17[4] which was adopted by Ithaca as the Ithaca 37 and also served as the basis for the Remington 31. The Model 31 was well liked,[5] but struggled for sales in the shadow of the Winchester Model 12. Remington sought to correct that in 1950 by introducing a modern, streamlined, rugged, reliable, and relatively inexpensive shotgun - the 870 Wingmaster.Sales of the 870 have been steady. They reached 2 million guns by 1973 (ten times the number of Model 31 shotguns it replaced). By 1996, spurred by sales of the basic "Express" models, which were added as a lower cost alternative to the original Wingmaster line, sales topped seven million guns. On April 13, 2009 the ten millionth Model 870 was produced, and the 870 holds the record for best-selling shotgun in the history of the world.[6]
[edit] Design details
The 870 features a bottom-loading, side ejecting receiver, tubular magazine under the barrel, dual action bars, internal hammer, and a bolt which locks into an extension in the barrel. The action, receiver, trigger system, safety catch and slide release catch of the Remington Model 870 shotgun are similar to those used on the Remington Model 7600 series pump-action centerfire rifles and carbines. The basic trigger group design was first used in the automatic 11-48.[7] 20 gauge stocks will also interchange. Several parts of the 870 will interchange with the semi-automatic Remington 1100 and 11-87.The original 870 models were offered with fixed chokes. In 1986 Remington introduced the new Remington "Rem Choke" system of screw-in chokes (also fitted to Remington model 1100 auto-loading shotguns at the same time). Initially, the Rem Chokes were offered on barrel lengths of 21", 26" and 28". It was not offered on 30" barrels, deer guns, target guns or as a retrofit.
Production 870s for over 30 years had a design whereby a user could either "short stroke" the action - not pull the forearm all the way back while cycling the action as they should - or fail to press a shell all the way into the magazine when loading such that the shell latch did not engage the shell, and such actions could tie up the gun.[8] This was caused by the shell which slipped out of the magazine under the bolt in the receiver to bind the action, requiring rough treatment of the action or even disassembly to clear by the uninitiated. The potential issue was resolved with the introduction of the "Flexi Tab" carrier. Guns with this modification can be identified by the "U"-shaped cut-out on the carrier, visible from below the gun. The cut-out allows the carrier to flex when the shell presses on it without binding the action.
[edit] Variants
There are hundreds of variations of the Remington 870 in 12, 16, 20, 28 gauges and .410 bore. From the original fifteen models offered, Remington currently produces dozens of models for civilian, law enforcement, and military sales. 870 variants can be grouped into:- Wingmaster – Blued steel with high gloss or satin walnut stocks. They have been offered in Skeet, Trap, and field configurations. Originally the basic Wingmaster was chambered for 2 3/4" rounds and came with a fixed choke, and the 3" chambered versions were designated Magnum models. Models built after 1986 offer the RemChoke Interchangeable choke tube system, and the 12 and 20 gauge versions are chambered in 3" for either 2 3/4" or 3" shells. Prior to the introduction of the "Police" model 870, altered Wingmasters were popular among law enforcement.
- Police – Blued or Parkerized steel with satin walnut, stained hardwood, or synthetic stocks. These models feature a stronger sear spring and magazine spring, and they receive extra care and inspections during assembly. Also often has an extended tube magazine.
- Marine – Nickel plated with synthetic stocks.
- Express - Matte blue/black bead-blasted with laminated hardwood or synthetic stocks and chambered for 2 3/4" and 3" 12 or 20 gauge shotshells. All Expresses have been chambered in 3" in 12 and 20 gauge, but markings have varied.
- Express Super Magnum – Matte black bead-blasted with laminated hardwood or synthetic stocks and chambered for 3½" 12 gauge shotshells.
- MCS(Modular Combat Shotgun)- A new modular version of the M870 which can be quickly modified with different barrels, magazine tubes, and stocks for different purposes, such as urban combat and door breaching.
[edit] Chinese M870
China has made unlicensed M870 copies by Norinco as the Norinco HP9-1 and used by the People's Liberation Army as the standard shotgun.[citation needed]However, the M870 copy is a widely-distributed design no longer under patent protection, and most parts interchange freely. In the United States, where Norinco products are specifically non-importable, this gun is imported and sold under the names Norinco Hawk 982 and Interstate Hawk 982.[citation needed]
[edit] Users
Challenger 2 (Tank)
| FV 4034 Challenger 2 | |
|---|---|
 Challenger 2 on manoeuvres on Salisbury Plain | |
| Type | Main battle tank |
| Place of origin |  United Kingdom |
| Service history | |
| In service | 1998–present |
| Used by | British Army, Oman Army |
| Wars | Iraq War |
| Production history | |
| Manufacturer | Alvis Vickers |
| Unit cost | ~£4,217,000 ~$6,797,660 [1] |
| Produced | 1993–2002 |
| Number built | ~446 |
| Specifications | |
| Weight | 62.5 tonnes (61.5 long tons; 68.9 short tons) |
| Length | 8.3 m (27 ft 3 in) 11.50 m (37 ft 9 in) with gun forward |
| Width | 3.5 m (11 ft 6 in) 4.2 m (13 ft 9 in) with appliqué armour |
| Height | 2.5 m (8 ft 2 in) |
| Crew | 4 (commander, gunner, loader/operator, driver) |
| | |
| Armour | Chobham/Dorchester Level 2 (classified) |
| Main armament | L30A1 120 mm rifled gun with 52 rounds |
| Secondary armament | Coaxial 7.62 mm L94A1 EX-34 (chain gun), 7.62 mm L37A2 Commander's cupola machine gun |
| Engine | Perkins CV-12 Diesel 1,200 hp (890 kW) |
| Power/weight | 19.2 hp/t (14.3 kW/t) |
| Transmission | David Brown TN54 epicyclic transmission (6 fwd, 2 rev.) |
| Suspension | Hydropneumatic |
| Ground clearance | 0.5 m (1 ft 8 in)[2] |
| Fuel capacity | 1,592 litres (350 imp gal; 421 US gal)[2] |
| Operational range | 450 km (280 mi)[2] road 250 km (160 mi)[2] off road |
| Speed | 56 km/h (35 mph)[2] 40 km/h (25 mph)[2] off road |
FV4034 Challenger 2 is a British main battle tank (MBT) currently in service with the armies of the United Kingdom and Oman. It was designed and built by the British company Vickers Defence Systems (now known as BAE Systems Land and Armaments). The manufacturer advertises it as the world's most reliable main battle tank.[3] As of January 2011, only three Challenger 2s have been damaged in combat, one of which was destroyed by another Challenger 2 in a friendly fire incident.
Challenger 2 is an extensive redesign from Challenger 1, the MBT from which it was developed. It uses the basic hull and automotive parts of its predecessor but all other components are new. Fewer than 5% of components are interchangeable. Challenger 2 has now replaced Challenger 1 in service with the British Army and is also used by the Royal Army of Oman. It has seen operational service in Bosnia, Kosovo and Iraq. During the 2003 invasion of Iraq the Challenger 2 tanks operating in the Gulf suffered no tank losses to enemy fire, although one was penetrated by an RPG-29 and another by an IED, causing crew injuries.
History
Challenger 2 is the third vehicle of this name, the first being the A30 Challenger, a Second World War design using the Cromwell tank chassis with a 17-pounder gun. The second was the Persian Gulf War era Challenger 1, which was the British army's main battle tank (MBT) from the early 1980s to the mid-1990s.
Vickers Defence Systems (later Alvis Vickers, now BAE Systems Land Systems) began to develop a successor to Challenger 1 as a private venture in 1986. Following the issue of a Staff Requirement for a next-generation tank, Vickers formally submitted its plans for Challenger 2 to the Ministry of Defence (MoD). Secretary of State for Defence George Younger announced to the House of Commons that Vickers would receive £90 million contract for a demonstrator vehicle, a deal that was finalised in January 1989.[4] The demonstration phase contained three milestones for progress, with dates of September 1989, March 1990, and September 1990. At the last of these milestones, Vickers was to have met 11 key criteria for the tank's design.[4]
In June 1991, after competition with other tank manufacturers' designs (including the M1A2 Abrams and the Leopard 2 (Improved)), the MoD placed a £520 million order for 127 MBTs and 13 driver training vehicles. An order for a further 259 tanks and 9 driver trainers (worth £800 million) was placed in 1994. Oman ordered 18 Challenger 2s in 1993 and a further 20 tanks in November 1997.
Production began in 1993 at two primary sites: Elswick, Tyne and Wear and Barnbow, Leeds, although over 250 subcontractors were involved. The first tanks were delivered in July 1994.
The Challenger 2 successfully completed its Reliability Growth Trial in 1994. Three vehicles were tested for 285 simulated battlefield days. Each day is known to have consisted of:
- 27 km (17 mi) of on-road travel
- 33 km (21 mi) of off-road travel
- 34 main armament rounds fired
- 1,000 7.62 MG rounds fired
- 16 hours weapon system operation
- 10 hours main engine idling
- 3.5 hours main engine running
Challenger 2 entered service with the British Army in 1998 (with the Royal Scots Dragoon Guards in Germany), with the last delivered in 2002. It is expected to remain in service until 2035. It serves with the Royal Scots Dragoon Guards, the Royal Dragoon Guards, the Queen's Royal Hussars, the King's Royal Hussars and the 2nd Royal Tank Regiment, each of which is the tank unit of an armoured or a mechanised brigade. One squadron of the 1st Royal Tank Regiment uses Challenger 2 in a training and demonstration role.
Deliveries of the Challenger 2 to Oman were completed in 2001.
The Trojan minefield breaching vehicle and the Titan bridge-laying vehicle based on the chassis of the Challenger 2 were shown in November 2006; 66 are to be supplied by BAE Systems to the Royal Engineers, at a cost of £250 million.[5]
A British military document from 2001 indicated that the British Army would not procure a replacement for the Challenger 2 because of a lack of foreseeable conventional threats in the future.[6]
[edit] Design
[edit] Armament
Uniquely among NATO main battle tank armament, the L30A1 is rifled, because the British Army continues to place a premium on the use of high explosive squash head (HESH) rounds in addition to APFSDS armour-piercing rounds. HESH rounds have a longer range (up to 8 kilometres / 5 miles) than APFSDS, and are more effective against buildings and thin-skinned vehicles.
Forty-nine main armament rounds are carried in the turret and hull; these are a mix of L27A1 APFSDS (also referred to as CHARM 3), L31 HESH and L34 white phosphorus smoke rounds, depending on the situation. As with earlier versions of the 120 mm gun, the propellant charges are loaded separately from the shell or KE projectile. A combustible rigid charge is used for the APFSDS rounds, and a combustible hemispherical bag charge for the HESH and Smoke rounds. An electrically-fired vent tube is used to initiate firing of the main armament rounds. (The main armament ammunition is thus described to be "three part ammunition", consisting of the projectile, charge and vent tube.)
The Challenger 2 is also armed with a L94A1 EX-34 7.62 mm chain gun coaxially to the left of the main gun, and a 7.62 mm L37A2 (GPMG) machine gun mounted on a pintle on the loader's hatch ring. 4,200 rounds of 7.62 mm ammunition are carried.
[edit] Fire control and sights
The commander has a panoramic SAGEM VS 580-10 gyrostabilised sight with laser rangefinder. Elevation range is +35° to −35°. The commander's station is equipped with eight periscopes for 360° vision.
The Thermal Observation and Gunnery Sight II (TOGS II), from Thales, provides night vision. The thermal image is displayed on both the gunner's and commander's sights and monitors. The gunner has a stabilised primary sight using a laser rangefinder with a range of 200 m to 10 km. The driver's position is equipped with a Thales Optronics image-intensifying Passive Driving Periscope (PDP) for night driving.
[edit] Defence
Challenger 2 is one of the most heavily armoured and best protected tanks in the world.[8] The turret and hull are protected with second generation Chobham armour (also known as Dorchester) the details of which are classified. The military claims that this material is twice as strong as steel.[citation needed] Explosive reactive armour (ERA) kits are also fitted as necessary. The nuclear, biological and chemical (NBC) protection system is located in the turret bustle.On each side of the turret are five L8 smoke grenade dischargers. Challenger 2 can also create smoke by injecting diesel fuel into the exhaust manifolds.
[edit] Drive system
- Engine: Perkins 26.6 litre CV12 diesel engine delivering 1,200 hp (890 kW).
- Gearbox: David Brown TN54 epicyclical transmission (6 fwd, 2 rev.).
- Suspension: second-generation hydrogas.
- Track: William Cook Defence hydraulically adjustable double-pin.
- Maximum speed: 37 mph/60 km/h (road); 25 mph/40 km/h (cross country)
- Range: 280 mi/450 km (road); 156 mi/250 km (cross country).
[edit] Crew and accommodation
The British Army maintained its requirement for a four-man crew (including a loader) after risk analysis of the incorporation of an automatic loader suggested that auto-loaders reduced battlefield survivability. Mechanical failure and the time required for repair were prime concerns.Like every British tank since the Centurion, and most other British AFVs, Challenger 2 contains a boiling vessel (BV) also known as a kettle or bivvie for water which can be used to brew tea, produce other hot beverages and heat boil-in-the-bag meals contained in ration packs.[9] This BV requirement is general for armoured vehicles of the British Armed Forces, and is unique to the armed forces of the UK.
[edit] Operational usage
[The tank was] "well armoured but in an operational theatre it's not the case that you can have absolute protection. This was not in any way new technology - the device involved was the same type of shaped charge that we have seen used very regularly. No-one has ever said Challenger tanks are impenetrable. We have always said that a big enough bomb will defeat any armour and any vehicle."
MOD Spokesman, speaking in regard to the Challenger 2[10]
In one encounter within the urban area a Challenger 2 came under attack from irregular forces with machine guns and rocket propelled grenades. The driver's sight was damaged and while attempting to back away under the commander's directions, the other sights were damaged and the tank threw its tracks entering a ditch. It was hit directly by fourteen rocket propelled grenades from close range and a MILAN anti-tank missile.[11] The crew survived remaining safe within the tank until the tank was recovered for repairs, the worst damage being to the sighting system. It was back in operation six hours later after repairs. One Challenger 2 operating near Basra survived being hit by 70 RPGs in another incident.[12]
There have been two Challenger 2s damaged in combat and one destroyed:
- 25 March 2003 - A friendly fire ("blue-on-blue") incident in Basra in which one Challenger 2 of the Black Watch Battlegroup (2nd Royal Tank Regiment) mistakenly engaged another Challenger 2 of the Queen's Royal Lancers after detecting what was believed to be an enemy flanking manoeuvre on thermal equipment. The attacking tank's second HESH round hit the open commander's hatch lid of the QRL tank sending hot fragments into the turret that caused an explosion of the stowed ammunition, destroying the tank and killing two crew members. It remains the only Challenger 2 to be completely destroyed on operations.[13]
- August 2006 - the driver of a Challenger 2, Trooper Sean Chance, lost three of his toes when an RPG-29 penetrated an ERA protected frontal part of the hull during an engagement in al-Amarah, Iraq.[14]
- April 6, 2007 - in Basra, Iraq, an IED shaped charge penetrated the underside of the tank resulting in the driver losing a leg and causing minor injuries to another soldier.[15]
[edit] Upgrades and variants
[edit] CLIP
A single Challenger 2 was fitted with the L55 and underwent trials in January 2006.[18] The smoothbore gun is the same length as the L30A1, and is fitted with the rifled gun's cradle, thermal sleeve, bore evacuator and muzzle reference system. Early trials apparently revealed that the German tungsten DM53 round was more effective than the depleted uranium CHARM 3.[8] The ammunition storage and handling arrangements will need to be changed to cater for the single-piece smoothbore rounds, instead of the separate-loading rifled rounds. In 2006, a figure of £386 million was estimated to fit all Challengers in the British Army with the Rheinmetall gun.[17]
Other improvements have also been considered, including a regenerative NBC protection system.[19]
In May 2007, the Ministry of Defence's Future Systems Group invited BAE to tender for the Challenger 2 Capability Sustainment Program (C2 CSP), which combined all upgrades into one programme. However, by mid-2008, the programme was in danger of slipping, or even being cancelled, as a result of defence budget shortfalls.[20]
[edit] Titan
[edit] Trojan
Main article: Trojan (vehicle)
Trojan is a combat engineering vehicle, styled as an AVRE for Armoured Vehicle, Royal Engineers in British Army parlance, designed as a replacement for the Chieftain AVRE (ChAVRE). It uses the Challenger 2 chassis, and will carry an articulated excavator arm, a dozer blade, and attachment rails for fascines. Like Titan, 33 are intended to reach service.[edit] Challenger 2E
Challenger 2E is an export version of the tank. It has a new integrated weapon control and battlefield management system, which includes a gyrostabilised panoramic SAGEM MVS 580 day/thermal sight for the commander and SAGEM SAVAN 15 gyrostabilised day/thermal sight for the gunner, both with eyesafe laser rangefinder. This allows hunter/killer operations with a common engagement sequence. An optional servo-controlled overhead weapons platform can be slaved to the commander's sight to allow operation independent from the turret.The power pack has been replaced with a new 1,500 hp (1,100 kW) EuroPowerPack with transversely mounted MTU MT 883 diesel engine coupled to Renk HSWL 295TM automatic transmission. The increase in vehicle performance is significant. The smaller volume but more powerful power pack incorporates as standard a cooling system and air-intake filtration system proved in desert use. The free space in the hull is available for ammunition stowage or for fuel, increasing the vehicle’s range to 550 km.
BAE announced in 2005 that development and export marketing of 2E would stop. This has been linked by the media to the failure of the 2E to be selected for the Hellenic Army in 2002, a competition won by the Leopard 2.[21]
[edit] CRARRV
The size and performance are similar to the MBT, but instead of armament it is fitted with:
- A main winch with 50-tonne pull (can exert 98 tonnes-force using an included pulley and anchor point on the vehicle), plus a small pilot winch to aid in deploying the main cable.
- Atlas crane capable of lifting 6,500 kg at a distance of 4.9 m (this is sufficient to lift a Challenger 2 power pack).
- In order to improve the flexibility and supplement the transportation power packs around the battlefield, the British Army procured a quantity of dedicated CRARRV High Mobility Trailers (CRARRV HMT). Each CRARRV HMT enables a CRARRV to transport a single (Challenger, Titan or Trojan) power pack or two Warrior power packs by altering the configuration of dedicated fixtures and attachment of fittings.
- Dozer blade to act as an earth anchor/stabiliser, or in obstacle clearance and fire position preparation.
- Large set of recovery and heavy repair tools including compressed air powered tools and arc-welding capability.
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