In late April, the United States Army announced that they’ll be replacing the M4 and other M16-based rifles with the SIG Sauer MCX SPEAR, chambered for new ammunition, the 6.8x51mm Common Cartridge (AKA .277 SIG Fury).
The change will be limited to close combat forces, defined as basically anyone who gets in line-of-sight with the enemy, while support forces and others who are armed will stick with the M4 and 5.56x45mm NATO.
This move has generated a fair amount of criticism from gun and military writers, YouTubers, and others who are aware of the history of the U.S. service rifle in the 20th century. Following World War II, it became apparent that the M1 Garand rifle needed improvement to better serve the armed forces. Experiments included replacing the eight-round en block clips with 20-round box magazines. The military was impressed. That led to a long design process, where other improvements to both gun and ammunition were made. The result was the M14 rifle, chambered in .308 Winchester or 7.62x51mm.
The military didn’t stick with the M14 for long. After less than a decade, it became clear that many soldiers just couldn’t handle the power when the weapon was placed in full-auto. It was also heavy and its wood stock didn’t hold up well in Vietnam’s humid environment. Worse, soldiers found themselves struggling to maintain fire superiority over enemy forces, who were using variants of the AK-47, chambered in a lower-powered intermediate cartridge (7.62x39mm). The AR-15’s lighter weight and lighter ammunition allowed soldiers to not only pack lighter, but carry and fire more ammunition. Its weaker round and buffer system proved to be a lot more controllable, too. By 1970, the AR-15 became the M16 and replaced most M14 rifles in the field.
Critics of the XM5 say that we’re basically going back in time and making the same mistake the military did with the M14. The 6.8x51mm ammunition is even more powerful than the M14’s 7.62×51/.308 Winchester ammunition, so the problem could end up being even worse. Some are even predicting that the Army will do what they did with the M14, and decide to ditch 6.8x51mm for another round later. But, it will be cheaper and easier because the XM5 can be quickly rebarelled and magazines can get a new follower to hold something else.
This historical lesson does raise the question of why the military moved from an intermediate round to a battle rifle round in the first place. The given answers I’ve seen from official sources indicate two things: The first one is that the new XM157 self-adjusting and networked 1-8x optic will reduce the need for more shots by making every shot more accurate. The second reason given is that the Army is preparing to face off against near-peer adversaries who have rifles that outperform AR-15/M16-based weapons. Unofficial, but very credible, explanations include lack of performance in Afghanistan and Iraq when taking long shots.
If you look at global service rifles, it’s pretty clear who they’re talking about when they say they chose the 6.8x51mm to counter near-peer adversaries. There are only two countries that could reasonably be considered near-peer: Russia and China. Russia’s rifles are mostly still chambered in the 5.45x39mm cartridge, an improvement of Vietnam-era ammunition with a smaller bullet to get closer to AR-15 performance, so they’re definitely not who the Pentagon is talking about. This process of elimination only leaves China.
While anyone can order a SIG MCX SPEAR and learn all about the XM5, it’s not easy at all to learn about China’s latest rifle: the QBZ-191 (and its variants, the QBZ-192 and QBU-191). Not only do they not let just anyone in China shoot it, but there’s an import ban on Norinco rifles in the United States, so we can’t get our hands on one even if they sold it and we wanted to buy it. Even information about the rifle has been very slow to trickle out onto the internet.
But, years of trickling can add up, and a video I recently found sheds a lot of light on the rifle:
There’s also a second video that updates some errors in the first video and provides more information that has trickled out since 2021:
It’s worth watching the whole of both videos, but there are a few key takeaways:
First off, the PLA and Norinco have abandoned the unique QBZ-95 bullpup design and basically went with their own variant of the AR-15. The separate upper and lower modular design, the use of a buffer tube, and even the trigger group (especially in the early prototypes before they went more in the direction of AK FCGs) all point to lessons learned from the U.S. service rifle. They even ripped off Magpul magazines for the most part. They’re using an optic very similar to the ACOG. The only truly substantive difference is that they went with a piston instead of direct impingement, but the civilian market has been experimenting with piston ARs for some time.
In other words, they’re doing what they almost always do: copy successful designs from other countries, tweak it a bit (it has a pretty decent side-charging handle system and a more durable bolt), and put it in mass production. But, to be fair, nearly all military rifles are variants or derivatives of the AKM, AR-15, or AR-18 these days, so China is hardly the only country doing this.
We also learn that at least some variants of the QBZ-191 will be issued with a wirelessly-connected optic that can allow an unknown set of advanced capabilities. It’s pretty clear that the XM157 optic and augmented reality helmet are an answer to this.
The other key difference from the M16 and M4 is that the QBZ-191 uses a higher-caliber round, the 5.8x42mm. This ammunition has been in use since the late 1980s, but has seen a lot of improvement over time. But, for the first 30 years of the cartridge’s life, most defense experts didn’t think that a war between the U.S. and China was very likely in the near-term. With more aggressive political moves in Hong Kong and more aggressive military moves in the South China Sea and near Taiwan, the chances of such a conflict seem a lot higher than they have in the past.
Specifics aren’t yet known, but we do know that the latest iteration of the 5.8x42mm round has better medium to long-range performance than earlier versions. This left the Pentagon with a need to outperform that ammunition and rifle. Whether the overwhelming difference in power is going to be advantageous or too much for effective use in the field is still an open question.
