The false promise of new technology: the British Army and the (new) calibre debate  

It is the lot of the infantry to hold ground and get shot at. This is the mundane history of the infantry, not the story you hear during training at Catterick or Brecon. But our social media feeds show us the reality. Soldiers in Ukraine are repeatedly filmed sitting in trenches waiting to be mortared, attacked by artillery or chased by a suicide FPV drone. Encounters involving small infantry units engaging each other are rare; instead, remote firepower remains the dominant killer on the 21^st century battlefield. Despite this, however, we are once again considering changes to small arms and small arms ammunition. This is being driven by discussions of lethal effect against body armour at over 600 metres. In this short commentary piece, I want to put the selection of a new rifle and ammunition into its wider societal, historical and organisational context. In the process I hope to persuade readers that the Army should not put new ammunition at the top of its priority list.

Although relative to the specific environment and type of conflict, comparatively speaking, the infantry is the least lethal branch of the armed forces.¹ Paradoxically, however, the infantry sits at the heart of the army’s identity and purpose. As representatives of the polity, infantry soldiers embody the social contract between the citizen and the nation. As I argue in Weapon of Choice this contract is underwritten by the engineer and the rifles they create.² Framed this way, the rifle is more than a weapon. It becomes the tangible symbol of the bond between the state and its soldiers.

If the state cannot provide a reliable and effective rifle, then it has failed at upholding its side of this foundational bargain. Getting small arms acquisition wrong not only jeopardises military effectiveness but it also risks the legitimacy of the sovereign state. The stakes are therefore far greater than the practicalities of small arms calibre or the frailties of weapon design. They touch on the very principles of governance and trust between the nation and its defenders.

If the state cannot provide a reliable and effective rifle, then it has failed at upholding its side of this foundational bargain.

Unfortunately, since at least the middle of the 19^th century, the introduction of every new service rifle with the British Army has been associated with controversy of some sort. The Martini Henry failed in the Sudan in 1884. The Short Magazine Lee-Enfield heralded arguments about the utility of the cavalry. The introduction of Fabrique Nationale’s Self-Loading Rifle occurred only because the Americans rejected an intermediate calibre in the 1950s. And of course, the SA80 failed in the desert during the First Gulf War and was subsequently suspended – at the request of the UK’s NATO delegate on small arms – from the Alliance’s Nominated Weapon List.³

Rifle failure

Given the symbolism and significance of the rifle and the long history of failure associated with its introduction into the Army, buying a new design of small arms and ammunition needs to be done with considerable care. In part this is because the UK no longer has the industrial capacity to produce a large fleet of weapons and will need to recalibrate existing ammunition production for a new calibre. Buying small batches of bespoke ammunition and specialist weapons does not necessarily create problems. However, buying a new fleet of rifles to fill the requirements of an entire Army brings with it unique practical challenges associated with introducing a new system, a new ammunition and the development of a new production line.

Take, for example, the Enfield Weapon System (EWS). The EWS was the pre-cursor to the SA80. Initially designed for a 4.85mm round, the weapon was specifically intended to allow the infantry to fight from an armoured fighting vehicle and be used in close quarters. The small calibre was selected primarily because 7.62mm ammunition was completely inappropriate for use in Northern Ireland where the round was causing severe injuries that were entirely unhelpful for winning the public relations battle.

The EWS was developed by a quickly stood up team of apprentices at the Royal Small Arms Factory at Enfield. The emergence of this small team was at odds with government policy which in the late 1950s had abandoned small arms design and development. By the late 1960s and early 1970s, conscious of impending privatisation and running out of orders for new weapons, the RSAF Directors decided to restart a small arms design section. In 1973, the General Staff met at Enfield and agreed to the EWS concept. This established a requirement for a family of weapons that would include a personal weapon and a replacement for the Bren L3 with what would later become the Light Support Weapon.

NATO standardisation

Following the NATO standardisation trials in the late 1970s, however, NATO selected 5.56mm and the EWS had to be redesigned for the new standard ammunition. Introducing a new calibre, a new rifle and going through a process of privatisation proved impossible to manage. When BAe Systems acquired Royal Ordnance, they moved small arms manufacture to a new facility in Nottingham. Even using specialist and precision assembly line technology, the move compounded the problems with the weapon. Having failed to deliver enough of either Tranche 1 or Tranche 2 weapons the government threatened legal action against BAe. When BAe responded with the potential of a counter suit for price fixing both parties withdrew to consider how best to proceed.

There were many reasons for SA80’s failure in the Gulf War. One of these, however, was the 5.56mm ammunition. Radway Green continued to standardise small arms ammunition on British propellant. The SA80 had been built around Radway Green produced ammunition. In their rush to have enough ammunition for use in the Middle East, the Ministry of Defence bought stocks from manufacturers in Switzerland and Belgium. These non-UK rounds used different makes of propellant, a factor that contributed to the failure of SA80 in the Gulf.

Of course, just because there have been teething problems in the past it does not follow that future weapon procurement will go the same way. Modern CNC tools are extremely precise and are more than capable of producing high quality weapons. But it is not the CNC’s capabilities that is at issue here. What smooths the introduction of new weapons, chambered to a new calibre on a new assembly line is experience and tacit knowledge. This knowledge can only be acquired the hard way, by actually doing the work. Yet, the capacity to produce large quantities of weapons at scale is something the UK abandoned in the 1990s when BAe Systems knocked down their manufactory in Nottingham and returned production to Germany and the Heckler & Kock arsenal in Oberndorf.

With international manufacturers committing to reshoring production, the UK can rely on contracted expertise. Whether this can compete with American, Belgian and German suppliers is open to question. Nevertheless, if a decision is taken to reshore production then overseas manufacturers will still have to acclimatise to British supply chains and that too will bring problems.

However, reshoring weapon production by itself will not be enough to guarantee security of supply at conventional war levels. This is particularly true if follow on orders do not materialise and production in the UK ends. The small arms market is already highly contested, and any British offering would have to be competitive on an international market. This implies the need to find a way to build expertise and retain production capacity as part of an industrial strategy. This is important as industrial capacity indirectly contributes to deterrence effect.

Even if quality control can be maintained and the risks associated with introducing new firearms managed, there are still good reasons for being cautious. The advantage of the infantry is that it is the most versatile branch of the army. This is useful in war when things never work out as intended. The infantry is always having to adapt to unforeseen challenges, something they are more adept at doing than other parts of the armed forces where a unit’s function is in part defined by its equipment.

However, we know that there is a recruitment crisis in the armed forces across all NATO powers, including the UK.⁴ There are all sorts of sociological reasons for this, but the net effect will be either (or a combination of): the re-introduction of some sort of limited conscription; or the armed forces try to exploit Artificial Intelligence either in decision-making or lethal autonomous weapons (LAWS).

When it comes to changes in recruitment practices, limited conscription implies that skill in marksmanship and close quarter drill will decline. 5.56mm ammunition was a compromise round, designed to facilitate shooting at limited ranges before closing on enemy positions where automatic fire was appropriate.

Given the weight of the round, soldiers can easily carry four magazines and keep the assault order weight down below 13kg. The decision to trade-off number of rounds against weight was framed by post-war research that showed 70% of the ranges at which a standing human target could be seen by a prone soldier were less than 274m and 90% at less than 822m.⁵

While improvements in optical sights can do much to extend the range at which soldiers can see out to 822m, algorithmically assisted fire control systems can improve the chance of securing a strike on a target. This could improve the lethality of the average conscript, but this comes at considerable financial cost and an assault order weight gain.

Putting more weight onto an already overburdened infantry is of course the last thing that is needed. Aware that the supply chain rarely delivers what frontline infantry need at a point when it is needed, soldiers tend to take everything they could possibly need with them into battle. This is partly a function of supply chain limitations while operating in global contexts.

Nevertheless, soldier burden hampers movement and has tactical implications. The infantry ideal is to pin down an enemy while advancing to close quarters. In Afghanistan, however, this was put to the test. Open terrain and poor marksmanship at ranges over 300m meant overburdened infantry struggled to close. The result was the return of 7.62mm ammunition and the introduction of the L129A1 Sharpshooter. A fifty-year-old ammunition gave the infantry section the means to hit targets at longer distances without having to spend £90k on a Javelin ATGM.

If the Army’s ambition is to strike targets equipped with level 3 body armour at 600m then an intermediate calibre or hybrid ammunition may be appropriate. The trade-off, however, will come in cost, soldier burden and the amount of ammunition a soldier will carry. Precision shooting may compensate for carrying fewer rounds, but experience indicates that this range will probably require an exquisite fire control system. This in turn comes with its own logistics burden. Batteries are already a significant challenge and will become more so as soldiers employ more data enabled devices.

Changing to an intermediate calibre, however, does not help soldiers slog it out in urban environments or dense jungles where longer ranges are limited. In a conventional urban war context, suppression may be just as important as precision. In an irregular urban war context, it is unlikely that an adversary will be equipped with level 3 body armour. In all cases the trade-offs associated with changing calibre appear to produce marginal battlefield gains for an enormous amount of supply chain risk and cost.

In the past decade, several of our international allies, including Norway, France, Estonia, Canada, Poland, and Germany, have all opted for 5.56mm weapon systems. This trend underscores a strategic alignment within Europe, ensuring compatibility and interoperability among NATO forces in an era where we return to great power competition. Despite the US Army’s adoption of the 6.8mm round for certain units, the US will continue to use 5.56mm for a significant portion of its forces. Maintaining the 5.56mm calibre makes strategic sense, aligning with current operational needs and the broader geopolitical landscape, particularly if the US shifts its strategic focus to the Indo-Pacific region.

The next 15 years

And this brings us to the looming challenge facing the infantry over the next fifteen years. This challenge does not actually come from potential adversaries but from an Army decision to make greater use of data, AI and LAWS. Arguably autonomous weapons already exist. Storm Shadow is already semi-autonomous. Introducing fully autonomous technology directly onto the battlefield, however, will almost certainly be resisted by the infantry.

LAWS and change fatigue

LAWS hold out the prospect of contributing to the lethality of the infantry without having to recruit more soldiers into the frontline. There are many legal, ethical and technical reasons why this is an extremely difficult thing to do. Military leaders may well insist that the technology is safe but the possibility that the infantry might welcome LAWS into their ranks nonetheless looks remote.

There are many reasons why the infantry will resist the adoption of LAWS. As US Navy Vice-Admiral Frank Whitworth, the head of Project Maven, notes, the hardest thing for AI to do is, “…distinguishing between enemy from non-enemy or combatant from non-combatant”.⁶ The key problem will be the fear that the technology will produce blue-on-blue incidents. Of course, LAWS designers may insist that blue forces wear an RFID tag or some other distinctive form of clothing. Training and drills build unit confidence and trust. Adding LAWS into this training routine might break down the infantry’s resistance to this technology. However, that will not stop an adversary mimicking the technology or finding ways to exploit it so it can be weaponised against blue forces.

Whatever the LAWS fanatics tell us about the future of the battlefield, we also know that the service branches and the UK Ministry of Defence have been dreadful at procurement. As the Army looks to introduce new “war winning” technology the more change programmes stack up in the MOD. Soldiers are already suffering from change fatigue as they get loaded up with one new leadership initiative after another.

In this context, Royal Marine efforts to change the calibre to 6.5mm Creedmoor for the L129A2 appear to be stalling. This is indicative of the problems the MOD have faced even bringing in small quantities of new ammunition calibres. Fortunately, however, a simple user level barrel change is able to revert the system back to 7.62mm, negating the organisational challenges that otherwise limit equipment change.

Change fatigue aside, it is almost a cast iron law of armed conflict that the Army will be expected to go into battle just at the point when the implementation of AI has failed to deliver on its promises. In these circumstances, it will be the infantry that have to put a sticking plaster on the ensuing mess, clearing up after the MOD and the ambitions of military leaders. If the infantry doesn’t have a weapon that is suitable for a limited conscription force, that will work irrespective of the best efforts of the digitisation enthusiasts, then we will have compounded our woes.

Thus, the prospect of moving from an all-volunteer to a limited conscription force brings with it the need for a proven rifle technology that anyone can use. Historically speaking, the infantry’s shooting skills have been notoriously poor. 5.56mm ammunition was introduced partly because its lighter weight allowed soldiers to carry more rounds. This was useful for generating suppressing fire, helping well-trained infantry close the distance to engage enemies more effectively at close quarters.

Equally, we already have a suitable round with a well-developed supply chain for those situations where range is important. Changing rifle and replacing the fleet of very capable SA80/A2 may well make sense over the next decade. Changing rifle and ammunition while reshoring industrial capacity, nonetheless, brings with it considerably greater risk. It is certainly possible to change rifle or calibre or develop industrial capacity but history shows us that to do all three at the same time is a recipe for weapon failure. While AI-enabled decision making and LAWS continue to shape procurement decisions, these technologies will take time to introduce and depending on their availability will provide only marginal benefit for troops holding ground on the frontline. In the meantime, between the promises of new technology and the practicalities of maintaining military power, changing calibre is a risky business.

Editor’s note: This article first appeared on Think Defence. We’re grateful to both the author and Think Defence for permission to reprint.

Cover photo: 5.56 ammunition. Credit: MOD.

1. For a more systematic survey of infantry lethality in different contexts, see Maj. James C. Beyer, MC, Maj. James K. Arima, MSC, and Doris W. Johnson, “Small arms fire accounted for between 14 and 31 percent of the total casualties, depending upon the theater of action: The Mediterranean theater, 14.0 percent; the European theater, 23.4 percent; and the Pacific theaters, 30.7 percent.” MEDICAL DEPARTMENT, UNITED STATES ARMY, WOUND BALLISTICS, 1962. Available at:https://achh.army.mil/history/book-wwii-woundblstcs-default.
2. Ford, M. (2017). Weapon of Choice: Small Arms and the Culture of Military Innovation. Oxford University Press, p. 26.
3. Author interview with Lt. Col. Tony Thornburn, former Commandant ITDU, Shrivenham, UK, 6 March 2012.
4. Patrick Bury, “The End of the All-Volunteer Force – or how I learned to stop worrying about recruitment and love selective conscription”, The RUSI Journal, vol. 169, no: 7, 2024. Available at: https://www.tandfonline.com/doi/full/10.1080/03071847.2024.2432820
5. Ford, M. (2017). Weapon of Choice, p.92.
6. Emily Chang, ‘Palmer Luckey wants to be Silicon Valley’s war king | The Circuit’, Bloomberg Originals, 16 May 2024. See 18 minutes 30 seconds into the interview. Available at: https://youtu.be/ItLFpYha6Wc?si=nONI9FTDmV_AsDo8. Accessed 12 August 2024.