EmericD said:

nincomp said: I think that a "golf bag" approach of matching the weapon mix to the mission is not unreasonable. It's just 2x to 3x more expensive. nincomp said: Although logisticians prefer everyone to use the same cartridge, it does not always make sense.  It makes sense from a logistic / strategic point of view, and in a high-intensity conflict that's as important as more technical considerations.

As we are looking more at "near peer" instead of COIN, these things need to be considered.

graylion said:

As we are looking more at "near peer" instead of COIN, these things need to be considered.

During WWI, France produced (and used) more than 8 billions of 8 mm Mle1886D cartridges. That's more than 100,000 metric tons of brass used only for the bullets.

During the height of the GWOT, I think that the US used around 1.2-1.4 billion of 5.56 mm ammo per year. At this time, a 5.56 mm cartridge was around 22-25 cents a pop, so that's ~300 millions of € of 5.56 mm ammo per year.

Most of those rounds were used for training, and we know from history that you need to fire more 7.62 mm ammo than 5.56 mm ammo to reach the same level of shooting proficiency (the historical trend is that you needed to fire less 5.56 mm ammo than 7.62 mm ammo to reach the same level of qualification).

With a full fleet of 7.62 mm rifles and a cost of 50 cents a pop, the bill would have raised to more than 800 millions per year (hypothesis: you need to fire 30% more round to reach the same level of proficiency).

With a full fleet of 6.8x51 mm rifles, the bill would be probably higher than 1.1 billion per year...

XM250:  So controllable, even a girl can shoot it.

YouTube

Lena Miculek shooting the new Sig Sauer Xm250 NGSW

? @SIG SAUER, Inc @Germanic Army @lenamiculekNEWINGTON, N.H., (April 20, 2022) - SIG SAUER is honored to be awarded the Next Generation Squad Weapons Syst...

This girl is Lena Miculek.

I doubt that any man on this forum can shoot nearly as well as her, and only a handful men around the world can do the trick.

That said, the weapon does appear controlable, but the ammo remains pretty heavy,

Brilliant response, Emeric. People forget that ammunition logistics are hugely important. 

Going back to the main thrust of my argument against NGSW, I don't think regular infantry battalions will need to engage enemies wearing body armour at 600 metres. They'll certainly need to do so at ranges below 300 metres. As Tony's iconic chart shows, only a small percentage of engagements took place beyond 400 metres. 

If the NGSW requirement is reduced to Level IV to 300 metres, this would allow a lighter, less powerful round with genuine weight savings to be adopted. A round like the Russian 6x49 mm fired at 3,500 would be awesome. 

With NGSW as it now is, we're seeing four standard loadings, Special Purpose (SP), General Purpose (GP), Reduced Range (RR) and Tracer (T). it looks like GP, RR and T may come in a standard bass cartridge and be fired at 62,000 psi. Whatever, I think we will need to get used to 6.8x51 defining the next NATO standard. 

Everything I've read here so far convinces me that 6.8x51 mm can replace 7.62x51 mm NATO, but not 5.56x45 mm. 

I think the US Army's new PAAC study will end-up trying to replace 5.56x45 mm NATO with something like 6x39 mm ARC. This could well make 6.8x51 mm redundant. In any event, I don't see the rest of NATO jumping on the NGSW bandwagon, at least in the short-term. 

Guardsman26 said:

People forget that ammunition logistics are hugely important.

With the US Army selecting the 6.8x51 mm; SOCOM adopting the 6.5 mm Creedmoor along the .300 AAC; some Navy operator inside SOCOM adopting the 6 mm ARC; UK SF adopting the 6.8 mm SPC and some SF units in Europe adopting the 260 Rem and the .300 AAC, life is going to be interesting, for sure!

And let's not forget the .338 Norma along the .338 Lapua, the .408 CT, the .375 Enabler and the .300 Norma (and the old .300 Winchester Magnum) for good measure.

Guardsman26 said:

Everything I've read here so far convinces me that 6.8x51 mm can replace 7.62x51 mm NATO, but not 5.56x45 mm. 

I tend to agree.  The big question to me is to what extent the 5.56x45 replacement will be hobbled by the existing AR15/M4 platform.  The barrel extension and bolt strengths pose pressure limitations and the magazine well dimensions pose cartridge size limitations.  At this point in time,  I would not bet on the reliability of 6mm ARC/65 Grendel-sized cases feeding through AR15/M4 magazine wells.   FWIW,  just this month the 65 Grendel forum had yet another thread concerning magazines and feed issues.

Guardsman26 said:

Going back to the main thrust of my argument against NGSW, I don't think regular infantry battalions will need to engage enemies wearing body armour at 600 metres. They'll certainly need to do so at ranges below 300 metres. As Tony's iconic chart shows, only a small percentage of engagements took place beyond 400 metres.

The chart shows >30% of engagements occurred beyond 400 meters.  I sure wouldn't classify 30% as a "small" percentage.

Guardsman26 said:

If the NGSW requirement is reduced to Level IV to 300 metres, this would allow a lighter, less powerful round with genuine weight savings to be adopted.

Color me skeptical.  I doubt that a round powerful enough to penetrate Level IV armor at 300 meters will be lighter than 5.56 NATO.

Guardsman26 said:

With NGSW as it now is, we're seeing four standard loadings, Special Purpose (SP), General Purpose (GP), Reduced Range (RR) and Tracer (T).

Same as it has been, except for a couple of name changes: 

Special Purpose = Armor Piercing

General Purpose = Ball

Guardsman26 said:

I think the US Army's new PAAC study will end-up trying to replace 5.56x45 mm NATO with something like 6x39 mm ARC.

PAAC study?

stancrist said:

PAAC study?

"Platoon Arms and Ammunition Configuration"

https://www.armytimes.com/news/your-army/2020/11/06/the-army-is-looking-for-a-new-machine-gun-and-the-marines-might-get-a-new-caliber-too/

Thanks!