U.S. Army Narrows Down The Field of Companies Trying For Next Generation Squad Weapons (NGSW) Using 6.8mm Ammunition

The Army announced on the evening of August 29th, 2019 that 3 companies were chosen to proceed to phase 2 of development of the Next Generation Squad Weapons with 6.8mm ammunition. The companies are (no surprises):

1) General Dynamics-OTS Inc. (OTS = Ordnance & Tactical Systems).

OTS has teamed up with True Velocity which has the True Velocity Composite Munition. True Velocity has been working on polymer case - metal cartridge head ammunition for some time.

Example photo below shows .50 BMG & 5.56mm polymer case cartridges produced by True Velocity (From the 2018 article True Velocity’s New Polymer-cased Ammunition
http://www.gunsandammo.com/editorial/true-velocitys-new-polymer-cased-ammunition/247607 )


2) AAI Corporation Textron Systems which has teamed with H&K and Olin Winchester ( https://www.thefirearmblog.com/blog/2019/08/30/937270/ )
Textron has been deep into the development of the radically different polymer cased Case Telescoping Ammunition or CTA.

The photo below (From a US Army RDECOM 2016 presentation entitled Cased Telescoped Small Arms Systems https://ndiastorage.blob.core.usgovcloudapi.net/ndia/2016/armament/18325_Phillips.pdf ) provides a general idea of CT ammunition.

3) Sig Sauer Inc . SIG announced back in May of this year that it had developed a 6.8 x 51mm cartridge which has a case that is a three piece construction hybrid case, a brass case tube, steel base and an internal clip to connect the two together. Makes one wonder if Shell Shock Technologies is involved with this.

Conceptual drawing of SIG 6.8x51mm cartridge

Note that phase 2 of development for the NGSW is scheduled to take another 8 years

Additional information & discussion here:



Additions, corrections etc. are most welcomed.



Interesting reading - thanks for compiling and sharing Brian.

We’ll have ray-guns & phazers by the time they get this thing 99% done. Either way, they are apt to then toss the whole thing aside like they did with the XM8 rifle.

Just got this in the mail this morning,

SIG SAUER Selected by U.S. Army for Next Generation Weapons with New Ammunition Technology, Lightweight Machine Gun, Rifle, and Suppressors
NEWINGTON, N.H., (September 3, 2019) – SIG SAUER, Inc. is proud to announce the official award of a contract by the U.S. Army in the down-select process for the Next Generation Squad Weapons (NGSW). The award encompasses the complete SIG SAUER system consisting of 6.8mm hybrid ammunition, a lightweight machine gun, rifle, and included suppressors. SIG SAUER will provide single-source manufacturing for ammunition, weapons, and suppressors allowing for less risk and increased capability for the U.S. Army.

“The U.S. Army is leading the world in the first significant upgrade to small arms in decades to meet the growing demands of soldiers on the battlefield. We are honored to have been selected for the Next Generation Squad Weapons program bringing increased lethality to the warfighter over the legacy weapons,” began Ron Cohen, President & CEO, SIG SAUER, Inc. “At the core of our submission is our newly developed, high-pressure, 6.8mm hybrid ammunition that is utilized in both weapons, and is a significant leap forward in ammunition innovation, design, and manufacturing.”

The SIG SAUER 6.8mm hybrid ammunition is designed for increased penetration at greater distances. Cohen continued, “using patent-pending technology the SIG SAUER Ammunition division has engineered a completely new cartridge resulting in a more compact round, with increased velocity and accuracy, while delivering a substantial reduction in the weight of the ammunition.”

The primary objectives set forth by the U.S. Army for the NGSW-AR was a weapon with the firepower and range of a machine gun, coupled with the precision and ergonomics of a rifle. The SIG SAUER NGSW-AR submission is an ultra-light, medium caliber machine gun with AR ergonomics, and chambered in 6.8mm hybrid ammunition. Features include quick detach magazines, side opening feed tray, increased available 1913 rail space for night vision and enablers, folding buttstock, and suppressor.

Additionally, the Prototype Project Opportunity Notice (PPON) requirements were inclusive of an NGSW-Rifle. The SIG SAUER NGSW-Rifle submission also chambered in 6.8mm hybrid, is lightweight and features a free-floating reinforced M-LOK™ handguard, side-charging handle, fully ambidextrous controls, folding buttstock, and suppressor.

“The U.S. Army challenged the industry to bring forward significant improvements to the legacy weapons. The SIG SAUER NGSW-AR is lighter in weight, with dramatically less recoil than that currently in service, while our carbine for the NGSW-Rifle submission is built on the foundation of SIG SAUER weapons in service with the premier fighting forces across the globe. Both weapons are designed with features that will increase the capabilities of the soldier,” commented Cohen. “The final component of the SIG SAUER Next-Generation Weapons System is our suppressor, which through exhaustively researched design enhancements, reduces harmful backflow and signature.”

As outlined in the recent award issued by the U.S. Army, SIG SAUER will deliver a complete SIG SAUER system inclusive of the SIG SAUER 6.8mm hybrid ammunition, lightweight machine gun, rifle, and suppressors.

“SIG SAUER has designed the most comprehensive solution to meet the requirements of the Next Generation Squad Weapons to enhance mission effectiveness. We are looking forward to partnering with the U.S. Army throughout this process and ensuring our soldiers are equipped for the demands of the modern battlefield,” concluded Cohen.


The folks who write press releases moonlight writing Fairly Tails… I work for the 6th largest Defense Contractor in the World (used to be #5). The stuff “corporate” publishes provides hours of laughter to those of us in Operations. ;-)


The SIG SAUER press release is ambiguous. It could be taken to mean that they have won the competition, or that they have been selected as one of the contenders.

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very true Tony

Like I said I’m just passing it on, & have no chicken in the fight.

True Velocity Shows the 6.8mm Composite-Cased Cartridge of General Dynamics NGSW Submissions



Photographs show a somewhat different profile for the 6.8mm.

Hrachya H. (TFB)
“However, the NGSW submission has a different design of shoulder and neck areas. As you can see, instead of a traditional shoulder and neck, the case has a rather small step from the case body to the bullet. I assume that step is designed to provide a headspacing point. I think the bullet should be supported inside the case. This design should be more reliable due to the elimination of a conventional case shoulder and neck which arguably has been the weakest point of polymer cased cartridges.”

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Sam, what is teh case length of this 6.8mm ?

My best; ‘guesstimate,’ for case length, would be 45mm.
The case (propellant) volume is almost a tube.

Sam, let’s see what will come up in future. Think one will get the measurements soon.

It appears that they have eliminated the brittle case neck here by making it thicker.
Maybe not the worst idea.

re, these plastic cases from a former CCI engineer. A couple of important points he mentions:

“Necessary with plastic shell cases to obtain sufficient bullet Pull and bullet push. Many other serious problems exist.
People designing this plastic nonsense have never been anywhere near Genuine combat where gun barrels can get red hot.
Can you Imagine chambering a plastic cartridge into a red hot barrel?”

The accepted wisdom is that; initially the chamber stays cooler as the polymer does not conduct combustion heat. However; the heat does not mysteriously disappear but; ‘probably,’ goes to the throat and the barrel. Ultimately; some of that heat will conduct back to the chamber. This is where the maximum sustainable rounds per minute (msrpm) parameter becomes important. In a critical situation, where fire superiority is needed, there is a temptation to exceed the msrpm. The end result is loss of function and component failure. This parameter is distinctly different to the cyclic rate.

There is a brief discussion of this parameter, with regard to the battle of Wannat, at the following:

Yes. I have heard from more than one source that when 100 rounds auto fire are put through a .50 BMG using polymer cases, the chamber remains cool enough to put your finger into it. That’s impressive.

The Textron polymer-cased-telescoped MG design is even less prone to chamber heating, because the chamber is separate from the barrel so will not be heated by conduction from the hot barrel.

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Sam3 the key word here is initialy, which in a sustained gun fight, has a lot to do with the end of the gun fight.

Hi Pete;
“initially,” to some degree relates to the fact that propellant combustion heat goes somewhere. The; ‘apparent 17%,’ of heat normally extracted by the ejection of a brass/metal case remains in the system and adds to the thermal load that needs to be removed somewhere by conduction and convection.
The answer may be new barrel alloys, or barrel sleeves, that are more heat resistant, but; that also conduct heat away. Some super alloys are more heat tolerant-resistant, but less efficient at conducting heat away.

Alternatively; quick change barrels might be helpful. The current infantry load difficulties might, however; preclude carrying spare barrels on a patrol. This might, however; work better at a FOB.

The answer, almost certainly, lies in training, fire control and a clear understanding of msrpm.

Propellant combustion heat has a way of; ‘catching up with you,’ and…is time on your side?

Below are patents assigned to True Velocity for those interested:

Keep in mind that True Velocity’s “composite” cases are not really polymer cases in the strict sense. They are a mixture of one or more polymers with other materials, such as glass fibers. Composites can have significantly different properties (including temperature resistance) than single component polymers. Adding glass fibers for example increases the strength, stiffness (elastic modulus) and high temperature creep strength of the base material (which appears to be a nylon engineering polymer).

It remains to be seen if they have solved the major problems with composite polymer cases, but the most significant advances in “hard” technology (as opposed to software/information tech) during the past few decades have been in materials and electronics. And I think that we have only seen the tip of the iceberg.


Mechanism for new rifle :-)

I’ve watched it for 30 minutes… it NEVER runs out of ammo!!


That proves that it’s a genuine product of the Wild West, as shown in so many Hollywood movies!