The Future of the Military Rifle

The three major(ish) powers in the world are all looking to replace their assault rifles with a new system in a caliber between 6.2 and 6.8mm. Is this trend a logical development of the past century and a half of rifle development or is it an answer to a misunderstood problem?

Peak WW1 Infantry rifle, the Mauser Gewehr 98:s, one with a trench kit consisting of an extended magazine and dust covers,

The humble rifle has been the piece that holds terrain in war since it replaced the smoothbore musket sometime in the first half of the 1800’s. Two innovations, metallic self contained case and smokeless powder brought around the classic infantry rifles which fought the two world wars. The development up to this point was remarkably uniform across the militaries around the world and these rifles are the benchmark all following generations are compared to power wise.

The initial power required from a military rifle were derived from two tasks. First was the ability to reliably stop a charging horse and the angry cavalryman riding it. The second perceived need was to be able to inflict casualties to enemies between 1000 and 3000 meters away with massed volley fire. While the utter desperation of the Russian army has actually made a cavalry charge a distinct possibility after being absent from the battlefields for seventy years, the volley fire mission was taken over first by machine guns and then by mortars already by the end of the First World War.

There was a much wider timeframe for the adoption of the next logical step, semi-automatic battle rifle. The United States and the USSR were at the forefront of this development, with the US being the foremost adopter of the semiautomatic rifle as their standard infantry weapon. But the adoption of the M1 Garand in the powerful .30-06 cartridge was a compromise between capabilities wanted and the economical means. The trials that led to the adoption of the M1, actually recommended the army to adopt a new cartridge, the .276X51 Pederssen. These numbers will come back to haunt us later on.

The United States, USSR and Germany fielded vast quantities of semi- and fully-automatic rifles during WW2. The victorious sides drew very different lessons from the war, with the US wanting to essentially just modernize the existing cartridge and rifle to a slightly more compact form factor with the same level of range and power as the venerable .30-06.

M1 Garand along with an STG-44, with a pistol caliber PPSH-41 submachine gun sandwiched in between.

The Soviets fielded a large number of 7.62x54R SVT rifles (caliber again a compromise caused by existing stockpiles) and submachine guns. After encountering the pinnacle of the German arms design the Sturmgewehr STG-44, they realized that the all out power was less important than the usability and short range firepower allowed by a true intermediate cartridge between the traditional pistol and rifle cartridges. It took two more wars for the US to reach the same conclusion and ditch their nearly full power battle rifle concept. Thus the 5.56x45 cartridge and the AR-15 platform were born.

Fast forwarding to 2026, both the US and Russia are using a similar, small bore, flat shooting intermediate cartridges in their M4 and AK-74 based rifles and carbines. The Chinese were playing catch-up with the two other global powers all the way to the 2000’s, but their current generation QBZ-191 family of weapons in 5,8×42 mm caliber are roughly equal to their counterparts.

The US small arms development benefits from the widespread adoption of the 5.56x45 cartridge and the dozens of different weapon platforms built around it. This knowledge pool isn’t limited to military rifles, but the innovation is also pushed by the civilian markets at a rapid pace. Russian development is much more linear and driven by the Russian military needs only. The Chinese have even less private development and no civilian gun culture at all to draw experience from.

A 75th Ranger Regiment soldier with a 14,5 M4a1 URG-I

The current pinnacles of the US military rifles, in this context I use the word rifle to cover carbines, assault rifles and battle rifles, are the Army’s M4 URG-I upgrade and the US Marine Corps’ M27. Both of these rifles are superficially similar to the M-16 and the basic AR-15 concept. The URG-I is an Geissle made direct impingement upgrade that turns the basic M4 into a precision weapon, capable of accurate fire out to 400m and beyond with excellent handling characteristics while fighting in confined spaces.

The M27 was first introduced to the USMC in its IAR automatic support weapon configuration, but the H&K 416 based gas piston operated rifle has quickly replaced the legacy M4 carbines and M16a4 rifles in the USMC infantry units. 

USMC Marine with an M27

The shorter barreled versions of the M27 provide a similar performance as the URG-I out to the 400m and the longer barreled variants can reach out much further. The M27 trades some of the URGI close quarters handling to more durability in the sustained automatic fire role, but are widely considered to be extremely effective and reliable with the current service ammunition they share. With precision oriented ammunition like the 77gr OTM bullet, both of these rifles can reach out to 800m in range conditions and with modern service optics.

When compared to the M8 and M7, both current rifles are lighter, have more ammunition on the weapon, more ammunition can be carried, have significantly longer service lives, have lighter recoil and better controllability. The M7 is already a step towards the existing rifles with a shorter barrel and lighter construction, but there is still a significant difference in handling.

Sig M8 rifle in 6.8x51

The new 6.8x51 cartridge offers increased range, muzzle velocity and penetration. The round is also called .277 Fury in the civilian market. So that would mean the new wunderwaffe is .277x51, where have we seen something similar? Oh, the .276x55 Pedersen a century before. 20 years after it was first proposed, the US Army forced NATO to standardize on the .30-caliber 7.62x51. And that was deemed to have too little ammo on the gun, too few rounds carried, too much recoil for full and so on.

Meanwhile the Russian army ramped up the speed of its first intermediate cartridge 7.62x39 by dropping the bullet diameter down to 5.45x39. Both of these calibers are still very much soldiering on across the planet. At longer ranges both tend to fall short especially in the accuracy department against the 5.56x45. The AK-74 platform is also getting a bit long in the tooth, despite the supposedly upgraded AK-12 slowly replacing it on the frontlines as 74’s are lost to attrition. 

The AK-12 has a myriad of problems, mainly stemming from designers lacking real world experience. The include unreliable optics mounting, uncleanable gas ports (Issue that was first identified with the M1 Garand) and a safety selector that can jam the entire action if used with infantry levels of hate.

Ukrainian National Guard soldier "Predator" from the 12th AZOV brigade with a captured AK-12

The AK-22 and its Designated Marksman Rifle companion are intended to use a “new and proprietary” 6.2x41 cartridge. Performance wise it’s closer to a spicy 5.56 NATO round, than the screaming 6.8x51.

But just like the idea of the 6.8x51 traces its roots to last century, the 6.2x41 is very close to an existing cartridge that has been used in precision competitions for decades, the 6mm PPC (6x38). It’s actually commonly manufactured by necking up a 5.45x39 Russian case to use a heavier 6mm  cartridge. if executed with quality components and paired with a rifle that has good ergonomics and a solid optics mounting system (both lacking in the AK-12 and -22) it could provide an excellent intermediate cartridge that would slightly improve the ballistics of the 5.45 NATO and allow the use of more intricately constructed armor piercing bullets. There are similar upgraded cartridges like the 6mm ARC that are based on the 5.56 NATO, but their use in an AR-15 based rifle has issues with durability, especially concerning the relatively narrow AR-15 bolthead.

PLA troops in their natural environment aka parade grounds, with the QBZ-191 rifles.

The Chinese  QBZ-191 has been under some testing to a so far undisclosed 6.8mm cartridge that looks like it’s going to sit between the US and Russian ones. On paper the Chinese QBZ-191 is comparable to the AK-12 or even superior to it, but nowhere near the handling and precision of the URGI or M27. The biggest limitation to the effectiveness of the Chinese rifles is still the relatively old fashioned and show oriented training of the PLA troops.

From the feedback of the actual users who know their stuff, Ukrainian frontline troops, western SOF and certain competition soldiers, we can deduce that there is really nothing fundamentally wrong with the current NATO standard 5.56x45 cartridge. Its latest iterations like the M855A1 have been very successful in modern combat operations, providing a good mix of weight, accuracy, penetration and terminal performance.

If the need for more penetration against armor is required, that can easily be achieved with the same weapons and casings by just changing the bullet design to be more penetration focused. One good example of turning an existing cartridge into a much more effective penetrator had been the 6.5×25mm CBJ, developed as a private venture in Sweden, that takes a pedestrian 9x19 pistol case and makes the 6.5mm composite bullet penetrate BMP-2 IFV armor from a pistol.

6.5x25CBJ compared to 5.56 NATO

-Petri Mäkelä