The history of the HK416 in modern warfare

When the HK416 started showing up on SOF compounds throughout Iraq, people noticed.
Joshua Skovlund Avatar
HK416 Marine Corps
U.S. Marine Corps Cpl. Ronald Garcia, a satellite communications operator with the command element, 31st Marine Expeditionary Unit, fires a HK416 during a deck shoot aboard the amphibious assault ship USS America (LHA 6), in the Solomon Sea, Aug. 12, 2023. (Lance Cpl. Elijah Murphy/U.S. Marine Corps).

In the early 2000s, operators in the U.S. military’s special operations community started using the Heckler & Koch HK416 as one of their primary battle rifles. It was initially meant to replace the Colt M4A1 but never realized that potential. 

Not just anyone in SOF had the opportunity to carry this German-made rifle into combat though. Rangers, SEALs, Green Berets, and others in SOF often work in the same areas as their higher echelon counterparts, but still carried the M4A1 or even FN SCAR during that timeframe.  

When the HK416 started showing up on SOF compounds throughout Iraq, hanging off the shoulder of operators grabbing a quick bite to eat in the chow hall — people noticed. It was the next new thing, but most never got a chance to use it. Unlike the SR25 sniper rifle, MultiCam uniforms, EOTech holographic sights, and high-cut helmets, the HK416 was one bit of kit that never made it into the wider U.S. Special Operations Command (SOCOM) inventory. 

Task & Purpose spoke with three special operators with first-hand experience using the HK416. Names and units are withheld to protect the operators’ identities.

What is the HK416

The HK 416 is a step away from the traditional operation of the Colt M4A1. Instead of a gas-operated, direct impingement system, it uses a gas-operated, short-stroke piston-driven operating rod. Ultimately, the piston setup was more reliable in testing, but compared to the M4A1, it’s more expensive and heavier.   

The operation of the HK416 is relatively similar to what operators were used to with the M4: the safety selector switch, magazine release, charging handle, and Picatinny rails were all the same or very similar. The cleaning procedures are different though, with the M4’s bolt carrier group and chamber needing to be cleaned more often when compared to the HK416’s piston system, which blows gas forward and away from the bolt carrier group — but still results in a different, but regularly required maintenance. 

“I wouldn’t say that it increased the amount of maintenance or even the frequency, really. It just adjusted how you had to clean it,” one operator said. “So instead of cleaning the chamber now you had to take off the foregrip to clean that piston system.”

For most people, that’s not a problem. But for the operators, who worked primarily at night and often used infrared lasers for shooting, removing the handrail to clean the piston system meant they had to re-check the zero on their lasers every time they cleaned the rifle.

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“You still got a lot of stuff in the chamber of the bolt carrier group, but not as bad as a gas impingement system. You traded that for having to clean the piston system because that thing would get fouled up quite regularly,” one operator said. “So, there are trade-offs with everything, but the value you got from that was you had a maritime weapon system that operated more optimally in water environments.”

The HK416 can go from submerged in water to firing outside of the water because of its piston system. A gas tube system will fill with water and must be drained to allow it to cycle again — an obvious problem for any force fighting in wet environments.  

But is it a better firearm than the M4A1? A second operator is not so sure. 

“It all depends on what we’re doing, right? I’m not one of those guys that gets wrapped around the axle about a specific brand or anything like that,” the second operator said. “It’s all about functionality and how it performs. It’s a tool.”

He said both rifles got the job done, but what he carried at any given time depended on the mission. 

The HK416 in modern warfare

The U.S. Marine Corps adopted the HK416 — for them, it’s the M27 — in 2011, but it had been in use for many years before that. One operator was around when the Marine Raiders first trialed it stateside. 

“We went through kind of side-by-side comparison tests [with the M4], on the flat range, as far back as we could hit with them,” the third operator said. “Reliability, there was just no comparison. We were big fans of the 416.”

Ultimately, the decision not to adopt them across the force was made because of the increased cost, but some units in SOF still wanted it and had the budget to put it in the hands of their operators. Due to the nature of their missions, they put the HK416 through the wringer.  

One factor they had to contend with was weight. The M4A1 weighs a little more than 7.5 pounds, while the HK416 weighs over 8 pounds. It’s not a significant difference if you aren’t carrying it for long distances, but for snipers on a long infil into an overwatch position, every ounce becomes noticeable. 

One operator described an operation he was on somewhere in Africa. He was carrying a Mark 13 .300 Win Mag in a gun bag on his back, along with all the additional tools he needed. His primary rifle for the walk to their hide site was an HK416, in case he needed to address any threats along the way. 

“It wasn’t noticeable to the fact that I was getting more fatigued because of it, but it was noticeable to where I was like, ‘fuck, my M4 was way lighter than this,’” the operator said.

Still, the HK416 was a solid tool for the operators using it. It was reliable in various environments and capable of fully automatic firing. It’s been fired for multiple thousands of rounds on full auto without any malfunctions. But, as with all firearms in the military, nothing lasts forever. 

The decline of the HK416 in special operations

it’s common for operators to fire thousands of rounds in training. One operator said he would guess he’s fired at least 10,000 rounds through the HK416 and spent roughly 4,000 hours training with it. 

So, naturally, any sort of problem that can happen will likely be found by the operators. They said there were issues with fine-tuning the pressure system for suppressed or unsuppressed use of the rifle. But, they adjusted to the system, and it was a matter of remembering to adjust the gas to a suppressed setting. 

“I was shooting anything from an 87-grain 5.56 all the way down to a 60-grain,” a third operator said. “It all just depends on what I need, which has huge implications with every function of the rifle.”

The variety of customized ammunition caused variances in pressure from what the rifle was built for, which led to cycling issues. Like the suppressor gas adjustments, it was a matter of fine-tuning.  

All three noted that there was a learning curve with figuring out what they had to frequently clean and what they didn’t, but ultimately found fail points and requested HK to make changes to improve the function and performance of their rifles.

At the time, Heckler & Koch didn’t have a major contract with the Department of Defense but was selling thousands of their rifles in Europe. So, addressing the needs of a group with only a hundred or so rifles didn’t make business sense. In the end, no one problem led to some higher echelon units phasing out the HK416. 

“Phasing out the HK — really, it wasn’t a bad rifle — I think it was the perfect storm. I think on the operational side, there wasn’t a ton of modularity. That impacts the operational side,” said the third operator. “At the time, weight was everything. Like literally, we’re humpin’ in very long distances on a nightly basis. So weight is a critical thing. If we regularly did stuff from vehicles or the helos, maybe we still would have the HK.”

The third operator said the HK416, compared to other rifles like the .300 Blackout or the SR25, is not just a simple matter of what’s better. 

“What is it designed for? And then what is that round designed for,” the third operator said. “So the best equivalent that I give when I’m training is like, okay, what’s a better vehicle to own? An F-350 diesel truck or a Ferrari?”

The HK416 and its use early in the War on Terror by some of the highest echelons of SOF is a blip in the history of modern warfare, but the Marine Corps implementation of the rifle may establish the rifle’s place as a significant platform improvement in conventional forces. 

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