SIG SAUER NSGW Automatic Rifle and Carbine

[greentips]

If you have not heard about the Next Generation Squad Weapon ( NSGW), it is the US effort to replace their 5.56 M249 ( aka C9 ) SAW and M4 carbine. The bullet is dictated by the US government to be a 6.8, and the bidders will have to create their own ammo out of this government 6.8 bullet. And the reason a 6.8 bullet is chosen because there is a combination of velocity and mass that will allow the design of AP ammo to defeat level 4 ceramic plate.

So yes, the solution to that velocity requirement is a 7.62 NATO sized cartridge and a pressure of 80,000 PSI. Sig Sauer came up with a brass/steel hybrid casing to achieve the velocity needs, ie, pushing a 130 gr bullet at 3000 fps over a 16" barrel. The commercial interpretation of this is the 277 Sig Fury now seen in the new SIG Cross rifle.

The NSGW "Carbine" submitted by Sig is essentially their 7.62 NATO MCX, SPEAR, chambered in their 6.8 ammo. Calling it a carbine is a bit interesting because it is really a 13" battle "rifle".

[greentips]

The more interesting part is the "automatic rifle", and what SIG submitted is basically a light machine gun chambered in full power cartridge in a 12 lb package. Instead of stamped sheet metal wielded together, or having steel plates riveted to form a box, the SIG is essentially an aluminum machine gun. this is basically a cutting edge FN MK48 type weapon, and have MORE range than the 27lb FN MAG C6. The recoil impulse of the SIG NSGW AR is that of a M4, with a reciprocating barrel recoil system.

While the gun is lighter than the M249 / C9, it has to run on a bigger cartridge. It is lighter, but it is actually bigger in size. Even if the 6.8 ammo is lighter than conventional cased ammo, it is still much heavier than 5.56. So the 4lb saved on the gun itself will be eaten up by heavier ammo, and also the gun is bigger, and the bigger ammo is eating up more load carrying space.



The receiver is aluminum, but the bolt appears to be running inside a steel insert. A QD "box" attachment point.


The current prototype doesn't have a QD barrel to reduce weight, but SIG stated that it does have a QD barrel mechanism for it, if required.


Feed cover hinges open to the right, feed tray up. Like the Negev and the new KAC LMG, the feed cover only opens over the feed tray.

[Milofficer]

Very slick. Awesome closeups too. Were any of the other NSGW prototypes out there? I definitely think Sig has a leg up in terms of controls / ergonomics

[greentips]

Very slick. Awesome closeups too. Were any of the other NSGW prototypes out there? I definitely think Sig has a leg up in terms of controls / ergonomics

The GD one is sitting at Bereta Defense booth, while the Textron's one is sitting with HK. I will be honest with you, those guns are BIG, especially the Textron's one. There is no way they can issue those monsters to infantry.

I am not the biggest fan of Sig Hybrid ammo because it is really not that light, but only SIG has both a useable belt fed gun and a useable "carbine"

On the other hand, maybe FN MAG / C6 are built strong enough to take a 80K PSI hybrid 7.62 ammo.

[vultr]

I thought they were moving to a 6.5 cartridge with the Mk48 and away from 6.8.

[yz295]

Absolutely beautiful

[chanrobi]

I thought they were moving to a 6.5 cartridge with the Mk48 and away from 6.8.

6.5 was what I understood to be an interim cartridge before doption of the 6.8

[nowarningshot]

So save 4 lbs on firearm. Add 20 for full combat load of ammo.

Its soon going to be a requirement to be a olympic weight lifter or wrestler to be a US grunt. They already grunt. Who of us can imagine humping 70% of their body weight in 40° heat.

[sonichanxiao]

Why they still have that forward assist, seems obsoleted.

[greentips]

So save 4 lbs on firearm. Add 20 for full combat load of ammo.

Its soon going to be a requirement to be a olympic weight lifter or wrestler to be a US grunt. They already grunt. Who of us can imagine humping 70% of their body weight in 40° heat.

Space is a big issue actually. The 6.8ammo is lighter but it is taking up as much space as the current 7.62 ammo. So it ends up everyone will be donating move space to carry ammo to support the "Squad automatic rifle".

The US army squad has 9 people with 2 SAWs, with 2X6.8 guns there may not be enough space to carry the same amount of ammo as with 5.56 SAW.

I think this is more promising as a a replacement for the platoon MG, like the M240 or C6, if it can pour down the same amount of sustained fire.