Future Industry Small Arms

A soldiers demonstrates the new L129A1 rifle nicknamed Sharpshooter. The rifle will improve the long-range firepower available on the front line. It fires a 7.62mm round and will enhance accuracy of engagement during longer-range firefights. This weapon will be used by some of the best shots in the Infantry. More than 400 of the semi-automatic Sharpshooter rifles have been bought as a £1.5M Urgent Operational Requirement. It is the first new Infantry combat rifle to be issued to troops for more than 20 years. The Sharpshooter complements the already potent range of weapons used by our forces in Afghanistan. Training on the rifles began in January 2010 and the first batch will be sent to Afghanistan later in the year. (©UK MOD Crown Copyright 2011)

It is worth emphasising the key argument in favour of the bullpup: the design reduces the overall gun length by some eight inches for the same barrel length, which is a huge reduction.  This is not just an advantage in urban fighting; it also facilitates fitting a suppressor, which is increasingly popular to reduce muzzle blast and flash and make firers more difficult to locate (it also protects the firer from long-term hearing damage).  With barrels of the same length, a bullpup with a suppressor will be about the same total length as a traditional rifle without one.

In addition, the adoption of a general-purpose intermediate round as proposed here would strengthen the case for the bullpup.  At the moment, it is possible to argue that 5.56mm rifles can have short barrels because they are now principally seen as short-range weapons.  On the other hand, 7.62mm rifles are being introduced for the long-range role and therefore don’t need to be very compact for urban warfare.  However, a single general-purpose infantry rifle in a general-purpose caliber must be well suited to both urban fighting and the long-range role.  As previously mentioned, this combination can be achieved with a modular traditional design with quick-change barrels of different lengths (as most recent designs offer), especially if the action design also allows the stock to be fully telescoped.  However, the bullpup layout does not require any such changes, and it is effectively two existing weapons – a rifle and a carbine – in one.

One issue which often receives little attention is recoil control, which as already observed is important in a rifle in order to facilitate training, rapid and accurate semiautomatic fire and controllable automatic fire.  In guns of similar type, recoil is largely a function of the gun weight and the cartridge power (specifically, the momentum – mass times velocity – as opposed to energy – mass times velocity squared).  However, the gun action can also have a significant effect, with advantages being demonstrated by soft-recoil mechanisms or even opposed-piston types like the AK-107.  The U.S. Army has recently been researching this and achieved reductions in the peak recoil force of up to 90% by using a counter-mass principle; but this would inevitably add weight.  Controllability in automatic fire can also be enhanced simply by reducing the rate of fire.  The very high cyclic rate common in modern 5.56mm small arms has little if any practical benefit and leads to more rapid ammunition exhaustion and barrel heating as well as greater cumulative recoil.

To achieve a large volume of automatic fire, as may be involved in fighting off a close-range attack, usually requires a heavier barrel to delay overheating.  However, the U.S. HPAWA project (High Performance Alloys for Weapon Applications) aims to result in barrels which will withstand far heavier rates of sustained fire, so that MGs can be issued with only one barrel.  Good progress has since been reported by ARDEC in the development of highly temperature-resistant cobalt alloys.  If such alloys reach production, this should enable a standard rifle to offer volumes of fire comparable with an IAR without any increase in barrel weight.  The problem of cook-off after an intense engagement could be addressed, if need be, by arranging for the gun to fire from an open bolt in automatic mode (although the USMC has not required this of their new IAR).  In other words, we could replace three weapons (carbine, rifle and IAR) with one.

Cartridges (from left to right): 5.56x45 NATO, 6.5x38 Grendel, 7x46 UIAC, .276 Pedersen, 7.62x51 NATO, 7.62x54R Russian (PKM), 7.62x39 Russian (AK). The 6.5mm Grendel and 7x46 UIAC are not current military cartridges, but represent the top and bottom of the calibre and power range judged to be suitable for a general-purpose military small-arms cartridge.

The design of the belt-fed LMG to accompany this rifle has not been discussed here, since the same design problems do not apply and existing designs could be adapted well enough to a new cartridge.  The adoption of a general-purpose intermediate cartridge developing significantly less recoil than the 7.62mm would however obviously allow the weight of the gun to be reduced without compromising reliability, which with the significantly lighter ammunition would deliver a substantial reduction in the weight currently carried by GPMG gunners and ammunition carriers.

Sights
Rifle and MG sights are currently making great advances in capability.  Variable magnification has been available on the specialist market for a very long time, and has now been joined by dual-magnification military sights, initially from Elcan (with 1-4x and 1.5-6x versions currently available), equipping the infantry with a sight suitable for both short and long-range use.  The addition of electronics is bringing even more dramatic advances, most obviously in night-vision capability.  In 2010, the U.S. military stated a requirement for a 1-4x day/night sight, merging thermal and light intensifying images, with a built-in rangefinder (and possibly a laser pointer), with a 3 lb (1.36 kg) weight, low power consumption and a price of $3-5,000.  With this kind of technology, such issues as air pressure, weapon cant and the effects of firing up or down hill can also be taken into account in providing an aiming solution.

Even more remarkable is the LIDAR (Laser Identification Detection And Ranging) unit developed by the Israeli Soreq Nuclear Research Center.  This works by firing a laser beam at the target, the reflection being captured by an array of photodiodes.  Fluctuations in the signals received by the photodiodes are used to detect the direction and velocity of any cross wind, which can have a major effect on hit probability at long range.  Something like this may well have an application in the DARPA One Shot next-generation sniper scope programme.  The One Shot programme is intended to enable snipers to be on target with the first round, under crosswind conditions, up to the maximum effective range of the weapon: a target of 65% probability of a first-round hit at up to 1,500 meters has been set when using long-range sniper rifles.

What all of this means is that we are soon likely to see practical day/night variable magnification sights which can take into account all of the usual factors which affect bullet trajectory.  All the soldier will have to do is to lase the target and the sights will automatically indicate the correct aiming mark to put the bullets into the target area.

Initially, such sights will be bulky, heavy and expensive and thereby restricted to snipers, but it is safe to predict that within the foreseeable future they will become smaller, lighter and eventually cheap enough for general issue.  This is enormously important because it means that the main objection to providing rifles with a long-range capability – that most soldiers will never be well-enough trained to hit anything at such ranges – is removed.  In conjunction with a long-barrelled standard rifle and long-range intermediate ammunition (and assuming a fundamentally accurate weapon and good-quality ammunition production), this also means that a separate DMR or sharpshooter rifle may no longer be required.  Potentially we could therefore replace four existing guns (carbine, rifle, IAR, DMR) with one.

The same sights and ammunition will of course also transform the long-range effectiveness of the belt-fed LMG, although the sustained-fire capability of a rifle with an advanced-alloy barrel may mean that fewer MGs will be needed.

Conclusion
So we have reduced our two cartridges to one, and our six or eight different guns to two – the general-purpose infantry rifle and the belt-fed LMG – without any loss in capability.  The practical and financial advantages of such a simplification would be huge, as would the boost to the capability of the infantry sections in whatever tactical circumstances may arise.

Various attempts have of course been made to introduce an intermediate round before, one of the first being the .276 Pedersen of the late 1920s.  After exhaustive tests this was recommended for adoption by the U.S. Army and the British were also very interested, but it was cancelled principally for financial reasons.  The modern equivalent is the 7×46 UIAC (Universal Infantry Assault Cartridge), an experimental round being developed by Cris Murray who was involved in the development of the 6.8mm Remington SPC.

All of the technologies which I have mentioned are either available now or are very likely to be available by the time the next generation of small arms has been developed.

If LSAT succeeds (and the plastic-cased telescoped version is currently looking promising), then a dramatic weight reduction can be added to the other advantages; it would mean that an LSAT intermediate round could weigh about the same as the current 5.56mm.

Now all we need is the people in the right places with the vision to see and drive towards what is possible, rather than simply going down the same old road because that’s what we’ve always done.  It is time for small arms to leave the 20th century.

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