This guest article was written by a retired naval weapons engineer with some small arms experience, as an exercise in seeing how much information can be gleaned from the internet on small arms, in the interests of ‘Thinking Defence’.
Future Small Arms for the British Armed Forces.
BACKGROUND HISTORY. A brief reminder of the types of ammunition used since WW2 will provide a context for reaching agreement on a basic requirement for a new NATO standard small arms ammunition.
During WW2 the Americans used the 30-06″ for their rifles and machine guns, the .30″ (7.62×33) for their carbines, and the .32″, .38″, 9mm , and .45″ for their pistols and submachine guns. The British used the .303 round for their rifles, light machine gun and medium machine gun, (the home guard used the 30-06″), the 9mm Parabellum and .45″ACP for their submachine guns and the .38″ and .455″ for their revolvers.
The only rounds the US and the UK had in common were the .38″ & 9mm pistol rounds. Hardly standardisation.
Meanwhile, in 1943 the Germans introduced probably the first of the Intermediate power rounds. This was the 7.9mmx33 Kurz, developed as a compromise between their 7.92mmx57 rifle round and the 9mmx19 Parabellum pistol round also used in submachine guns. The low recoil force of this new round allowed it to be used in a light assault rifle in the fully automatic mode like a submachine gun while still being able to engage targets out to 300m when used as a rifle. The actual bullet diameter was 8.22mm (.324″) weight 123 grains. The 7.92mm size refers to the diameter of the bore between the lands of the rifling. The 33mm size refers to the case length.
The Soviets were quick to follow suit with their own Intermediate Power round. The 7.62mmx39mm round was a rimless bottlenecked intermediate cartridge that was introduced in 1944. The actual bullet diameter was 7.92mm (0.312″). Shortly after WW2 the world’s most widespread military rifle, the Kalashnikov AK47 was designed for this cartridge. The cartridge remained in service until the 70’s.
As expected, Intermediate Power rounds aroused great interest among the remaining Allies. The British were particularly impressed and in the late forties began development, with later help from Fabrique Nationale of Belgium, and Canada, of an intermediate round of their own. The British, by experimenting with bullet diameters, cartridge types, ballistic coefficients, etc, eventually produced the .280″ (7mm x43mm) round which not only had a sufficiently low recoil force of 10 J to permit an assault rifle to be used in fully automatic fire, but matched or exceeded the .303 full sized rifle round in performance at 1,000 yards due to its efficient ballistic coefficient. Britain also developed a bullpup assault rifle the EM-2, and a machinegun, the Taden (a belt fed Bren Gun), to take the new round; both were arguably ahead of their time.
This round was agreed by many to be years ahead of its day. Unfortunately, the USA considered it at the time to be too weak, and despite an agreement that the NATO member states would develop common small arms and ammunition in cooperation, the USA secretly developed their own .30 round. Britain was on the point of issuing the .280 round and its associated EM-2 rifle and Taden machinegun when an election brought Churchill back into office. He considered that standardisation was more important than individual weapon performance and in 1954 the British Army was obliged to accept the .30 American round, now designated the NATO 7.62x51mm round. The EM-2 could not be modified to accept the 7.62mm round and so Britain adopted the Belgian FN FAL self-loading rifle, expecting the USA to keep an agreement to do the same; but the US chose their own M14 rifle. The new 7.62x51mm round had much the same ballistic performance as the old British .303″. The disadvantages of the 7.62x51mm round are its weight at 25.4 grams which limits the number of rounds the soldier can carry, the recoil energy of 16 joules which is too powerful for automatic fire in a handheld assault rifle, and the indifferent ballistic coefficient of the bullet which limits its effective range.
During the late 50’s the US army started a project to develop a 0.22″ calibre, high-velocity firearm to replace their M1/M2 0.30″ Carbines, the M3 and Thompson Submachineguns, the M1 Garand SLR, and the 1918 BAR light machine gun; despite having earlier rejected the .280×43 as too weak! However the US Army staff still insisted that they needed a more powerful round for the replacement of the M1 Garand and the 1918 BAR, and so the M14 SLR and M60 GPMG used the 7.62mmx51 round. For the new .22″ round Eugene Stoner was invited to scale down his experimental 7.62mm lightweight AR10 rifle. The calibre was to be 0.22″ with the bullet exceeding the supersonic speed at 500 yards and capable of penetrating one side of a US steel helmet at 500 yards. The wounding capability was to equal the M1/M2 Carbines, even though many in the army considered this was not powerful enough. The starting point was the high velocity .222″ Remington round, normally used for shooting small game at longer ranges and commonly called a ‘varmint’ round. After extensive development, the round that emerged in 1963 was a .223″ round, the 5.56mm, Ball, M193. This cartridge and its associated M16A1 Rifle, a development of Stoner’s Armalite AR-15 rifle, entered service in the USAF 1964.
In Vietnam, the 7.62mm M14 SLR proved to be too heavy and cumbersome for jungle warfare and was replaced by the Stoner M16A1. The US army also realised that for the same weight of 10kg, a soldier with a Kalashnikov was carrying 360 rounds compared with only 280 rounds for the 7.62mm M14. When the M16A1 was introduced the US soldier was able to carry 600 rounds.
In action conditions, the 5.56mm round occasionally caused terrible wounds. This was at first thought to be caused by the bullet tumbling after striking but was later found to be due to the round fragmenting. The round complied with the Geneva Convention for small arms, which prohibited the use of rounds that expand or flatten, by being of full metal jacket construction. However, some countries question the legality of the 5.56mm round. In 1977, NATO members signed an agreement to select a small calibre cartridge developed by FN of Belgium from the M193, to be named the 5.56×45 NATO to complement the 7.62×51 NATO round.
The 5.56mm round in the M16A1 proved to be satisfactory in the shorter range jungle conditions of Vietnam, once reliability problems were solved. However, when faced with the longer ranges in the semi-arid areas of Iraq and Afghanistan using the later version of the round, the M855, troops started reporting that the rounds did not provide enough stopping power. Troops engaging insurgents at less than 150m found that they were not causing lethal effects even with two hits and would not penetrate vehicle windscreens even with multiple hits at short range. Most of these reports probably came from users of the M4 carbine, a shorter, lighter version of the M16A2 assault rifle with a barrel reduced from 20″ to 14.5″. Tests have shown that M855 rounds must fragment to cause serious wound damage. If they do not fragment the effects are much reduced. The M855 must be travelling at 2,500 ft/sec to reliably fragment, but even with a full-length barrel the round will drop below this speed at 200m, and the shorter barrelled carbine round will drop below this speed at 150m.
As about half of the small arms attacks in Afghanistan were launched from 300-900 metres an answer had to be found for engaging the enemy at over 300m. The US Army answer to this problem was a heavily modified M16 series rifle intended to give the Squad Designated Marksman increased accuracy out to a range of 600m. Although the British Army use the SA80A2 rifle which has a longer barrel than that used by the M4 there were still complaints about its effectiveness at ranges over 200m. The British Army solution was a 7.62mmx51 ‘Marksman’ rifle, one per section. The weapon chosen was the American Lewis Machine Tool Co. LM308MWS, designated L129A1 in British service.
Although suitable for standard M80 Ball the RG 155gr sniper round was so much better than the standard ball it was made the official issue round. The maximum effective range of this combination is 800m. The British Army also used the L86A2 Light Support Weapon as a marksman’s rifle. This version of the SA80 has a heavier 27.9″ barrel and a bipod. It was originally intended to provide fire support at section level but as it is not belt fed, and as an overheated barrel cannot be changed, it was not suitable for sustained fire and was replaced in the fire support role by the FN Minimi. The 5.56×45 FN Minimi can fire from both belt or box magazine feeds and has a quick change barrel and a Bipod. It fires from an open bolt to avoid cook-offs. Even so, some British Army sections carried 7.62mm FN MAG GPMGs as the section support weapon, despite the extra weight of both weapon and rounds.
Before I close this section, a few words on the relative reliability of the different self-loading actions.
The Kalashnikov AK 47, the M1 Garand, the British Bren Gun, and the FN MAG GPMG, all noted for their reliability and durability, all use a Long Stroke Piston forced to the rear by expanding propellant gas bled through a port in the barrel near the muzzle end. The piston acts directly against the bolt carrier to eject the spent cartridge, and then the bolt carrier and piston move forward driven by the return spring to load the next round. As the bolt carrier is driven all the way to the rear by the piston this makes for more reliable ejection and reloading. Propellant gases are kept well away from the receiver. Even after 70 years, AK47s remains the most popular and widely used assault rifle in the world due to their substantial reliability under harsh conditions. The disadvantage is an increase in weight, but not excessively so. AK 47s are not noted for their accuracy which it is thought can be upset by the increased mass of reciprocating parts during firing which takes place with the long stroke piston above the barrel, although this does not seem to affect the accuracy of the Bren Gun and the FN MAG GPMG.
The SA80 which employs features of the Stoner AR18 uses the Short Stroke Piston method. The short stroke piston is also driven by propellant gas bled through a port in the barrel. The short stroke piston imparts a short sharp blow to the bolt carrier which continues to the rear under its own kinetic energy. The advantages are weight saving and lower reciprocating mass while firing. The disadvantage is that fouling in the receiver on the path of the bolt carrier can affect its rearwards movement and thus adversely affect ejection or reloading.
The AR15 (M16A2) uses the direct impingement method. The direct impingement method of operation vents hot gas from partway down the barrel through a tube to the working parts of a rifle where they directly impinge on the bolt carrier. The advantage is a simpler and lighter mechanism. Another advantage is that the moving parts are placed in-line with the bore meaning that the line of sight is not disturbed as much by reciprocating mass. The disadvantage is that the hot propellant gas (and the accompanying fouling) is blown directly into the action parts. The operation increases the amount of heat that is deposited in the receiver while firing, which can burn off lubricants while depositing fouling. The bolt, extractor, ejector, pins, and springs are also heated by the same high-temperature gas. These combined factors reduce the service life of these parts, and the mean time between failures. Early models of the M16A2 had problems with ejection due to this cause.
The above story shows how battle experience, combined with weapon and ammunition development, has lead to the proliferation of both weapons and ammunition moving away from the benefits of standardisation.
Within the next ten to fifteen years, from 2018, the armies of the USA, Canada, UK, Germany, and France will need to replace or at least update their small arms. However the relative weakness of the defence budgets of both the USA and the UK, and/or the lack of priority for new infantry weapons while both countries are avoiding major ground conflicts following wars in Iraq and Afghanistan, means that in the short term all that can be expected are improvements in the existing status quo; i.e. a continuation of 5.56mm and 7.62mm ammunition and their associated weapons.
The shortcomings in the present weapons and ammunition are as follows:
- Lead cores need to be eliminated from all rounds in order to comply with environmental standards.
- The 7.62mm recoil force of 16 Joules is too severe for the automatic fire to be used in handheld assault rifles. The hard recoil causes some operators to find it difficult to maintain even single shot accuracy.
- The weight of the 7.62mm round at 25.4 grams means that for a 10-kilogram load, a 7.62 user can carry only 390 rounds compared with 613 rounds for the AK47, or 813 rounds for the 5.56mm SA80A2. This must be viewed in the context that the probability of making a hit is proportional to the number of rounds available.
- The GPMG is considered by many to be too heavy to act as the Section Light Machine Gun, and the FN 5.46mm Minimi has been issued instead, despite reservations about its effective range. Some units do carry the GPMG as the section light machine gun despite the extra weight.
- Reports from Afghanistan indicate that the 5.56 round was not powerful enough to engage opposition at ranges over 300 metres. As half the engagements with Taliban fighters took place at ranges from 300 to 600 metres the NATO forces were out-ranged. In the UK the problem was partially overcome by issuing a 7.62mm rifle to a designated marksman in each Section.
- Currently, the Infantry units and their suppliers have the logistic problem of requiring three different types of small arms ammunition to be supplied, namely 9mm, 5.56mm and 7.62mm. Cost and manpower savings up the logistic chain back to the manufacturer could be made if the assault rifle and the machine gun used the same ammunition. This ideal was achieved by Britain in the 1940s with the .280 (7mm) round for the EM2 rifle and Taden machine gun, both fully developed, but then abandoned for standardisation reasons when the Americans adopted the 7.62mm round.
Some of these shortcomings can be addressed in the near term and the most likely changes will be:-
- The imminent introduction of the steel-tipped, copper cored, US developed M855A1 5.56mm and M80A1 7.62mm Enhanced Performance Rounds or a similar British equivalent round. They not only eliminate lead from their construction on environmental grounds but are claimed to have improved penetration of steel targets, more consistent wound effects in soft targets, and better accuracy.
- In the longer term, development is nearing completion in the USA of polymer cartridge cases instead of brass cases. They offer a 35% reduction in weight over brass cases and are claimed to offer cooler operation of the chamber when firing.
- Approval of the SA80A3 Upgrade of the existing assault rifle is nearing completion. The changes include:-
- A safety stud placed above the change lever on the trigger mechanism housing to ensure that this lever does not over-rotate.
- The Weaver rail on top of the upper receiver being replaced a full-length Picatinny rail – this will allow the day sight and night sight to be mounted in tandem.
- A new foregrip, or quad rail, as part of the new full-length rail which will be attached slightly differently to the current one allowing the barrel to be more free-floating than at present, to improve accuracy and consistency.
- Redesign of the A3 upper receiver for improved reliability and maintainability over the current A2 variant.
- A colour change to Dark Earth for better compatibility with MTP camouflage uniforms.
- There may be weight saving measures not mentioned above, for example, a titanium piston.
- Introduction of a Lightweight GPMG. A lightweight version of the L7A2 GPMG has been developed by H&K with a reduction in weight of 1.8kg (4lbs). Changes include:-
- A fluted barrel,
- A Picatinny rail for sights on the top cover,
- A folding butt,
- An improved feed tray.
- A Dark Earth coloured receiver body matching the new MTP camouflage.
This gun does not include the titanium receiver body which is still under study at Cranfield. If this development is practical and affordable the weight saving would be around 3kg (6.6lb). The Lightweight GPMG remains a stated Army requirement.
The above improvements are expected to extend the life of 5.56mm and 7.62mm ammunition and weapons until approximately 2035/40. This will allow time for the development of the next generation of small arms ammunition and associated weapons, which has already started in the USA.
Such is the predominance of the US arms industry, the influence of their supporting political lobbyists and the sheer size of their armed forces, that any changes in NATO standard ammunition must have the support of the USA. In practice, this means that any developments in NATO ammunition will take place in the USA. Even if the Europeans proved to have a better design of ammunition the Americans are unlikely to accept it, despite getting it wrong in 1954 with the 7.62 which was too heavy with excessive recoil force and poor ballistic coefficient, and again in 1977 with the 5.56 which was too light, easily deflected, great for prairie dogs but reportedly not so good for Taliban.
It is therefore in the interests of the UK to agree as soon as possible with Canada, Germany, France and any other NATO countries, their basic Future NATO Small arms Ammunition (FNSA) Design Requirement. They should then use every ounce of their collective influence to persuade the USA to base their developments on their jointly agreed requirement.
Once the FNSA Round has been developed and agreed NATO countries, singly or in partnership, should be free to make their own ammunition to this standard, and design and make their own weapons to use this ammunition. The USA may well ask for contributions to the development costs of this ammunition.
The UK and other NATO countries may well have different Infantry Doctrines to the USA and therefore may not use the same weapons even though using the same ammunition. For example, proposals emerging from the USA include a suggestion for ALL infantry weapons to have a range of 1,200 metres which suggests replacing the assault rifle with something more elaborate. Another proposal is that the assault rifle fires 20mm grenade rounds which can be set to explode at a range set by a laser range finder built into the weapon, which also has a conventional rifle set below the 20mm barrel (ie two magazines will be required). It appears that the USA is heading for more complex, bulkier, and costly weapons.
It is for consideration that in the UK the equipment for the infantry section has already become too heavy and complex. They are already required to carry their individual weapons and ammunition, a range of day and night vision aids, radio communication aids, body armour, bayonet, hand grenades, entrenching tool, rations, kit, etc. plus as required the 27lb MBT LAW antitank weapon and 19lb Matador anti-structure munitions. What is required is a return to a more “nimble” soldier at section level with light simple robust weapons. What can weapons developments do to reduce this problem, apart from making lighter weapons and ammunition? It is for consideration that he need for indirect fire support at the lowest level could be met by supplying each section with a lightweight handheld target acquisition sight no bigger than a pair of binoculars, which could radio target data to a handheld mortar computer no bigger than a mobile phone, for the control of 60mm mortars held at platoon level. The technology to do this should be achievable by 2035. The 60mm mortar bomb would provide a much greater terminal effect than either the proposed US 20mm grenade rounds or the existing 40mm grenades fired from an under-slung tube launcher on the assault rifle. This will relieve the Section of a load of transporting a quantity of 40mm grenades and the H&K under-slung launchers and their sights on two of the weapons.
This paper, therefore, addresses the UK requirements for Future Small Arms. The main aims will be:-
- To introduce a common ammunition for both Assault Rifles and General Purpose Machine Guns.
- To introduce an Assault Rifle with a maximum effective range of 800m, and a General Purpose Machine Gun with a maximum effective range of 1,200m.
- To reduce as far as possible the weight of individual rounds of ammunition and weapons consistent with achieving the maximum effective ranges above.
Four outline specifications;-
- Annexe A, a draft outline specification for the Future NATO Smallarms Ammunition (FNSA).
- Annexe B, a draft outline specification for a Future British Assault Rifle.
- Annexe C, a draft outline specification for a Future British General Purpose Machinegun.
- Annexe D, a draft outline specification for a Future Self Defence Weapon.
Finally, the United States should be made aware that if they are not prepared to design and develop a round to meet the FNSA basic requirements of the rest of the NATO countries, there may have to be two standards, one for the USA and another for the rest of NATO. This would be a retrograde step.
In considering the design of new ammunition and weapons it is as well to remember the words of Kalashnikov himself when asked about the design process. “A lot of Russian soldiers ask me how new weaponry is designed. This a very difficult question. Each designer has his own paths, his own successes and failures. But one thing is clear; before attempting to create something new it is vital to have a good appreciation of everything that already exists in this field. I myself have had many experiences confirming this to be so.” ( Kalashnikov modelled the long stroke action of the AK47 on the US M1 Garand SLR)
Annex A. Outline Design Requirement for the Future NATO Smallarms Ammunition (FNSA).
This outline requirement acknowledges the predominance of the United States of America in developing NATO Standard ammunition. It acknowledges, therefore, the developments that have already been carried out by them.
American studies in 2006 by the Joint Services Wound Ballistics-Integrated Projects Team recommended a calibre in the 6.5mm to 7mm range.
The Textron Company has, on behalf of the US Army, spent ten years developing 6.5mm(.266″) Cased Telescopic (6.5mm CTA) rounds which are reaching maturity. They have also developed a prototype Machinegun and a prototype Carbine (assault rifle) in which to prove the ammunition, but would probably not meet British requirements. Much more testing is required, but the results so far look promising.
An outline design requirement for Future NATO Smallarms Ammunition (FNSA) is proposed below. This is for discussion with other NATO countries, prior to approaching the USA.
- A Cased Telescopic Ammunition (CTA) round shall be developed, using as a starting point the 6.5mm, 8oz (135grain) bullet already developed by Textron (this low drag bullet is only 5 grains or 3.6% lighter than the 7.62mm but is 20% longer and therefore has a better ballistic coefficient). It shall be suitable for small arms use, ranging from assault rifles used in single shot or automatic fire out to 600m, through designated marksman use out to 800m, to suppressive fire from light and medium machineguns out to 1,200m. It shall have sufficiently low recoil energy to permit the assault rifle to be fired comfortably in automatic fire while matching or exceeding the accuracy, penetration and residual energy requirements stated below.
- The details of the barrels required to meet the performance standards shall be defined by the ammunition designer and used to confirm the performance standards. Two barrels are required, the first suitable for an individual assault rifle using either automatic fire or single aimed shots out to 800m, and the second for sustained suppressive fire in a machinegun out to 1,200m. The barrel descriptions shall include materials, chamber dimensions, barrel length, rifling twist, bore measured between the top of the lands of the rifling, and the finish of the chamber and bore. In the case of the ammunition being used in a short carbine barrel, the drop in performance standards, and any changes in rifling required shall be defined.
- Low overall ammunition weight is important regarding the number of rounds that can be carried as this reflects on the hit probability of rounds carried by the soldier. Therefore the maximum weight of the new round shall not exceed 15 grams (7.62mm = 25.4grams), and a 20 round loaded magazine shall not exceed 450grams (1lb). One kg of 7.62mm rounds would be 280 rounds but 1Kg of 6.5mm CTA would be 475 rounds. However low ammunition weight shall not over-ride the need to meet the ballistic performance targets.
- The recoil energy per round shall not exceed 10 Joules.
- The range for the penetration of one side of a steel helmet shall be not less than 800m for the shorter barrel and 1,200M for the longer barrel.
- The residual energy at 1,200m shall be not less than 300 foot-pounds. (7.62mm = 230ftlbs)
- The vertex height for 600m range shall not exceed 1m.
- Accuracy shall be less than 1 MOA in test conditions using the standard barrels defined above.
- The SAMMI chamber pressure shall not exceed 65,000 psi.
- For environmental reasons, the bullet shall contain no lead or radioactive material.
- For legal reasons, the bullet shall not fragment on contact with human tissue at any range.
- The ammunition shall be suitable for use in either polymer type box magazines or belt feed.
- The ammunition shall be suitable for use in temperatures between +50°C and -50°C.
Annex B. Outline Design Requirement for a Future British Assault Rifle (FBAR).
- THE ACTION. The FBAR shall employ a rotating bolt, gas operated long stroke piston, and fire from a closed bolt. The action shall operate in either single shot self-loading mode or fully automatic mode with a rate of fire between 600 and 700 rounds per minute. The cocking lever shall not reciprocate when firing. The bolt carrier shall remain in the rear position when the last round is fired from the magazine, and be ready to fire again when the magazine is replaced. The exhaust gas shall not impinge on the operator’s face or hands. The FBAR shall use a ‘bullpup’ configuration with the magazine behind the pistol grip in order to reduce the overall length of the weapon. It shall use a detachable 20 round polymer magazine. In order to achieve the required degree of accuracy and muzzle energy the FBAR shall have a barrel length up to but not exceeding 20″, cold forged with a chrome lining for long life and easy cleaning, and chambered for the 6.5mm CTA round. The barrel shall be free floating as much as the gas take-off will allow. It shall be fitted with a slotted flash eliminator and shall accept the British L3A1 socket bayonet.
- THE FURNITURE. The stock shall be made of synthetic material and be neat, uncluttered and easy to clean, and in a Dark Earth colour matching the new MTP camouflage. The stock shall be resistant to abrasion, impact, oils, fuels, greases, acids, strong alkalis, moisture, UV light, high humidity and extremes of temperature between +50° and -50°C. The straight buttstock shall be in line with the axis of the bore such that the recoil force will not cause the muzzle to climb between shots, and shall be positioned so as to give a comfortable alignment of the eye with the sight line. The fore-end shall cover the top of the barrel to prevent heat distortion of the line of sight. The edges of the top, bottom and sides of the for-end shall be parallel with the barrel and fitted with Picatinny rails on the top, bottom and sides parallel to the barrel for accessories. The rail on the top shall be long enough to permit the use of day sight and night sight in tandem. A vertical handgrip with a telescopic bipod shall be fitted to the bottom Picatinny rail. There shall be storage for cleaning gear and oil bottle. There shall be provision for a sling.
- THE CONTROLS. The mode of fire (single shot or automatic) shall be selected by a two position lever which shall be operated without taking the hand off the pistol grip. A manual cross bolt safety catch shall be fitted above the pistol grip. The FBAR shall be suitable for use by both left handed and right handed operators. Controls such as the mode selector, safety-catch, magazine catch and cocking lever shall operable by either left handed or right handed shooters or readily interchanged between the two. The cartridge case ejection shall be readily changeable between the left side and right sides. The magazine catch shall be positioned so as to avoid accidental release of the magazine. The trigger and the controls listed above shall be capable of being operated wearing cold weather gloves. The trigger shall have a two-stage crisp action with a first stage pull weight of 5 to 8 lbs, and a second stage pull weight of 1 to 1.5lbs.
- THE SIGHTS. The optical sight(s) shall be mounted on a Picatinny rail on the top of the receiver long enough to permit a day sight and night sight to be fitted in tandem. The optical sight is expected to be an Elcan Lightweight Day Sight (LDS) with 4x magnification. On top of this sight is a low profile ‘Red Dot’ Non-Magnifying Reflector Close Quarters Battle (CQB) sight. The section’s Designated Marksman will probably be issued with a more powerful ACOG 6×48 sight complete with CQB sight (his weapon will be otherwise the same as the rest of the section). In case the optical sights fail the FBAR shall have ‘flip-up’ iron sights, with an aperture back-sight adjustable for ranges between 100m and 600m, and a blade foresight on the front of the receiver.
- THE DIMENSIONS. The overall length of the FBAR shall be not more than 30″ (752mm). The length of pull from butt to trigger shall be 15″. The fore-end shall extend at least 10″ forward from the trigger. The maximum weight of the FBAR, with a loaded magazine, Elcan Lightweight Day Sight, and sling attached, shall be not more than 8 lb (3.63kg) .
- THE ACCESSORIES. Accessories supplied with each FBAR shall be, a Blank Firing Attachment, a Blank Firing Magazine, an Adjustable Sling, an Oil Bottle, and Cleaning Gear.
- RELIABILITY. The FBAR shall operate reliably when subjected to all the appropriate MOD tests for resistance to sand, mud, rain, immersion in salt water, snow, and temperatures between +50° and -50°C; plus drop tests, cook-off tests, etc. The FBAR shall achieve an average reliability of 25,000 mean rounds between failures.
- MAINTAINABILITY. Field strip, cleaning and re-assembly of the FBAR shall be straightforward with no tools required. Securing pins shall be captive to avoid loss. Complete strip, refurbishment and re-assembly by armourers shall not require the use of special-to-type gauges or tools.
- PERFORMANCE. The FBAR shall be capable of placing 6 consecutive rounds in a 4″ square at 200m. The Maximum Effective range of the FBAR shall be 600m when fitted with an optical sight with x4 magnification, and 800m when fitted with an optical sight of x6 magnification.
- CARBINE VERSION. A Carbine version with an overall length of 22″ and using as many components as possible of the FBAR shall be introduced for use by crews of all manner of vehicles, gunners, crew-served weapons operators, helicopter crews, signallers, infantry NCOs, special forces, etc.
- CONSTRUCTION. The feasibility should be examined by making a one piece combined receiver and furniture using the 3D printing technique should suitable material be developed.
Annex C. Outline Design Requirements for a Future British General Purpose Machinegun (FGPMG).
- THE ACTION. The FGPMG shall employ a tilting block bolt, gas operated long stroke piston, and fire from an open bolt. The FGPMG shall use a linked belt feed, fitted ahead of the trigger. The means of inserting a belt shall be easy to operate and difficult to get wrong. The bolt carrier shall remain in the rear position when the last round is fired from the belt and be ready to fire again when a new belt is fitted. The action shall operate in fully automatic mode only, with a rate of fire between 600 and 1,000 rounds per minute. The cocking lever shall not reciprocate when firing. An eight position gas regulator valve shall adjust the rate of fire. The exhaust gas shall not impinge on the operator’s face or hands. In order to achieve the required degree of accuracy and muzzle energy, the FGPMG shall have a barrel up to but not exceeding 24″, cold forged with a chrome lining for long life and easy cleaning, chambered for the 6.5mm CTA round. The barrel shall be fitted with a carrying handle, slotted flash suppressor and a blade foresight. The barrel shall be easily removed and replaced using the carrying handle to avoid touching the hot barrel. Changing a barrel shall not take longer than 6 seconds.
- THE FURNITURE. The weapon shall be neat, uncluttered and easy to clean. The Butt-stock and Pistol Grip shall be made of synthetic material that is resistant to abrasion, impact, oils, fuels, greases, acids, strong alkalis, moisture, UV light, high humidity and extremes of temperature between +50° and -50°C. The Butt-stock, Receiver Body and Pistol Grip shall be finished in a Dark Earth colour matching the new MTP camouflage. The butt shall be positioned so as to give a comfortable alignment of the eye with the sight line and shall be able to be folded and clipped back against the receiver body to reduce the weapon length if required. There shall be provision to attach a sling. A folding bipod, adjustable for height, shall be attached to the front of the weapon and shall be folded back and clipped in place when not in use. There shall be provision for a sling, and storage of an oil bottle and cleaning gear
- The FGPMG shall be capable of being configured in either of two roles, namely as a Light Machinegun or as a Medium Machinegun. The Light Machinegun shall use a buttstock and fire from a bipod. The Medium Machinegun shall fire from a tripod and may have the buttstock and bipod removed if preferred. An attachment bush, similar to that on the FN MAG GPMG, with a bore of xx mm is to be built into the lower part of the receiver for attachment to the tripod or other mounts.
- THE DIMENSIONS. The overall length of the FGPMG shall be not more than 38″ (752mm). The length of pull from butt to trigger shall be 15″. The maximum weight of the FGPMG, unloaded, shall be not more than 18 lb (8.2kg).
- THE CONTROLS. A manual cross bolt safety catch shall be fitted above the pistol grip. The trigger shall have a two-stage crisp action with a first stage pull weight of 5 to 8 lbs, with a second stage pull weight of 1 to 1.5lbs. The FGPMG shall be suitable for use by both left handed and right handed operators. Controls such as the safety-catch, magazine catch and cocking lever shall be capable of operation by either left handed or right handed operators. The trigger, cocking lever, safety catch, cartridge belt loading arrangements and barrel changing arrangements shall permit operation while wearing cold weather gloves.
- THE SIGHTS. A Picatinny rail long enough to permit a day sight and night sight to be fitted in tandem shall be fitted along the top of the receiver for sights or other accessories. The rail shall be suitable for current sights such as the Elcan 4x Lightweight Day Sight, the ACOG 6×48 LDS and the Viper2 Thermal Imaging Sight. Iron sights shall consist of a forward blade which is part of the barrel assembly and adjustable for windage. A folding aperture sight shall be hinged at the rear of the receiver body, adjustable for ranges from 400m to 1,800m at 100m intervals. When the sight is folded down a larger aperture sight is to be presented for CQB. A bracket shall be fitted on the left rear of the receiver body to take a C2 Indirect Fire Sight.
- THE ACCESSORIES. Accessories supplied with each FGPMG shall be, a Blank Firing Attachment, an Adjustable Sling, an Oil Bottle, Cleaning Gear, and a Spare Barrel.
- RELIABILITY. The FGPMG shall operate reliably when subjected to appropriate tests for resistance to sand, mud, rain, immersion in salt water, snow, and temperatures between +50° and -50°C., plus drop tests, cook-off tests etc. The FGPMP shall achieve an average reliability of 25,000 mean rounds between failures.
- MAINTAINABILITY. Field strip, cleaning and re-assembly of the FGMG shall be straightforward with no tools required. Securing pins shall be captive to avoid loss. Complete strip, refurbishment and re-assembly of the FGPMG by armourers shall not require the use of special-to-type gauges or tools.
- PERFORMANCE. The FGPMG shall place 6 consecutive rounds in a 4″ square at 200m. The maximum effective range of the FGPMG shall be 1,200m.
- CONSTRUCTION. The feasibility should be examined by making a one-piece combined receiver and furniture using the 3D printing technique should suitable material be developed.
Annex C. Outline Self Defence Weapon (SDW) Requirement for Support Troops.
The new British Future British Assault Rifle (FBAR) using the new 6.5mm CTA round, is relatively costly and requires extensive periods of training and practice in order to achieve maximum effectiveness.
There is a need therefore to provide a less costly, lighter, simpler weapon which does not require extensive training, for the self defence of Support Troops, such as the Logistic Corps, Adjutant Generals Corps and Aircraft Ground Crew, etc. (An example being the M1 0.380″ Carbine issued to Support Troops in the US Armed Forces in WW2.)
A less costly and lighter weight ammunition is required as well, and there is a need to standardise on the range of ammunition supplied to troops. The only other type of small arms ammunition, other than the 6.5mm CTA round, and the 0.338″ (8.6mm) Sniper round, is the 9mm NATO round. This ammunition is supplied for use with the Glock17 Gen4 pistol issued for self-defence purposes. However, a pistol requires much practice to be accurate and has a maximum effective range of only 50 metres even in skilled hands. It has been shown, from experience with the Sterling Sub-Machinegun, that the NATO 9mm round can have a maximum effective range of 200 metres against soft targets in the right weapon. This is considered adequate for a Self Defence Weapon (SDW).
An outline specification for a suitable Self Defence Weapon (SDW) is proposed as follows:-
- THE ACTION. The SDW shall employ mechanically delayed blow-back action and fire from a closed bolt. The SDW action shall operate in the single shot, self loading mode only. (Automatic fire is not recommended for support troops who, as wartime experience has shown, can quickly exhaust their ammunition supplies, often for little effect.) In order to achieve the required degree of accuracy and muzzle energy the SDW shall have a 15″ barrel, cold forged, with a chrome lining for long life and easy cleaning, chambered for the NATO 9mm round. The barrel shall be free-floating in the stock. (The above requirements are expected to result in a muzzle energy of at least 560 lbft, compared( with 420 lbft for a pistol; greater accuracy than a weapon firing from an open bolt, and much better accuracy than a pistol.) A small segment-shaped recess in the top of the receiver and the chamber of the barrel shall permit a visual examination to check if there is a round in the chamber. The SDW shall accept the British L3A1 socket bayonet.
- THE FURNITURE. The SDW shall be neat, uncluttered and easy to clean. The one piece stock shall be made of synthetic material that is resistant to abrasion, impact, oils, fuels, greases, acids, strong alkalis, moisture, UV light, high humidity and extremes of temperature between +50° and -30°C. The colour shall be Dark Earth matching the new MTP camouflage. The straight through butt stock shall be in line with the axis of the bore and shall be positioned so as to give a comfortable alignment of the eye with the sight line. The fore end shall cover the top of the barrel to prevent heat distortion of the line of sight. The fore end sides and bottom shall be parallel to the barrel and shall be drilled and tapped for the possible later fitting of Picatinny rails parallel to the barrel for accessories. It may be necessary to make the upper half of the fore end separate from the one piece stock, this is permissible. The SDW shall use the standard Glock17 pistol magazine holding 17 rounds. It shall be loaded into the weapon’s pistol grip. There shall be provision to attach a sling. There shall be storage for an oil bottle and cleaning kit.
- THE CONTROLS. A manual cross bolt safety-catch shall be fitted above the pistol grip. The trigger shall have a two-stage crisp action with a first stage pull weight of 5 to 8 lbs, with a second stage pull weight of 1 to 1.5lbs. Controls such as the safety-catch, magazine catch and cocking lever shall be capable of being operated by left or right handed operators or be readily interchangeable. The cartridge case ejection shall be clear of the operators face whether fired left or right handed. The trigger, safety-catch, magazine catch and cocking lever shall permit operation while wearing cold weather gloves. The magazine catch shall be positioned so as to avoid accidental release of the magazine.
- THE SIGHTS. The sight shall be a simple, low profile ‘Red Dot’ Non-Magnifying Reflector Sight, such as the Shield Close Quarters Battle (CQB) sight already in service. It shall be mounted on a Picatinny rail on the top of the receiver, (not the fore end of the stock). In case the reflector sight fails, the weapon shall have a V-shaped rear sight built into the top of the CQB sight and a ‘flip-up’ blade foresight, factory zeroed to 100m.
- THE DIMENSIONS. The dimensions of the SDW shall be as follows. The length of pull from butt to trigger shall be 15″ (380mm). The fore end shall extend at least 10″ forward from the trigger. The overall length of the SDW shall be not more than 30″ (762mm). The maximum weight with a Red Dot Sight, loaded magazine and sling attached shall be not more than 6lb (2.7kg).
- THE ACCESSORIES. The following Accessories shall be supplied with each SDW, A Blank Firing Attachment, a Blank Rounds Magazine, an Adjustable Sling, an Oil Bottle, Cleaning Gear, Four Glock 17 magazines in two twin Carrying Pouches with belt loops, and an L3A1 Socket Bayonet and Sheath.
- RELIABILITY. The SDW shall operate reliably when subjected to appropriate MOD tests for resistance to sand, mud, rain, immersion in salt water, snow, and temperatures between +50° and -20°C, plus drop tests, cook-off tests, etc. The SDW shall achieve an average reliability of 25,000 mean rounds between failures.
- MAINTAINABILITY. Field strip, cleaning and re-assembly of the SDW shall be straightforward with no tools required. Securing pins shall be captive to avoid loss. Complete strip, refurbishment and re-assembly by armourers shall not require the use of special-to-type gauges or tools.
- PERFORMANCE. The SDW shall be able to put 6 consecutive shots into a 12″ square at 100m. The SDW shall have a maximum effective range of 200m against soft targets.
- SILENCED VERSION. Because the 9mm round is subsonic the weapon lends itself to silenced operation by special forces. A limited number of the SDWs shall be produced with the following changes. Provision shall be made to fit a screw-on silencer. A raised threaded portion shall be machined on the barrel instead of the facility to fit the L3A1 bayonet. (The weapon may exceed the overall length of 30″ when the silencer is fitted.) A catch shall be fitted that will prevent blow-back cartridge ejection and reloading occurring on firing, resulting in quiet operation. Ejection and reloading shall then be carried out manually, at a time convenient to the operator by pressing the catch down and using the cocking lever. It shall be possible to operate the catch without taking the hand off the pistol grip. Holding the catch down while pressing the trigger will result in a normal single shot, semi-automatic fire taking place. A night sight shall be supplied instead of the Red Dot sight.