Pretty well-written article, although IMO this weight comparison is flawed and rather unfair:

"A loaded XM5 with the XM157 optic will weigh about 3 lbs., 4 ozs., more than a loaded M4A1 with an M68 optic."

An apples-to-apples comparison to M4A1 with suppressor, polymer mag, and XM157 optic (or at least a LPVO) would show less weight difference.

stancrist said:

Pretty well-written article, although IMO this weight comparison is flawed and rather unfair

I think it's both a fair and unfair comparison. 

Unfair, for as you say the weight is based on the NGSW with its big FCU and suppressor vs M4 with a red dot and IR laser, no suppressor. 

Yet the comparison is fair if we view the systems by their 'fighting weights' as the two systems are actually deployed by the US Army.

For the last 20 years, the basic M4 loadout for the Army in Iraq and Afghanistan was the M4 with either a Aimpoint or ACOG + IR laser, no suppressor. That represents its 'fighting weight'.

If NGSW is intended to always be suppressed and use a special FCU, then thats its 'fighting weight.' 

And so an Army soldier transitioning from a M4+M68+IR to NGSW+FCU+Suppressor will notice a +3lb weight gain in what they're carrying. 

Since I cannot resists any NGSW related meme if I encounter one:

The original Overmatch weapon:

https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device)

gatnerd said:

Yet the comparison is [also] fair if we view the systems by their 'fighting weights' as the two systems are actually deployed by the US Army.

I would be inclined to agree, but that idea ignores some pertinent facts.

1.  The US Army would not be the sole user.  The XM7 would also be used by the Marines, who have used suppressor-equipped M4 carbines for several years.  https://youtu.be/8-FuLw_6KgQ?t=98

2.  Since we're talking about the future, nobody knows how the M4 will be "actually deployed" if the XM7 is fielded.  The XM157 FCS is not dedicated to NGSW guns; it could also be used on the M4.

3.  Since we're talking about the future, nobody knows for certain if the XM7 will be "actually deployed" only with the suppressor attached.  Evidence suggests that it may not.

Are we totally sure that M7 is going to be fielded in numbers as an "assault" rifle? 

I find it really difficult to understand

I think they're gonna go through with it, and if they do well... 

It will tell us some stuff 

poliorcetes said:

Are we totally sure that M7 is going to be fielded in numbers as an "assault" rifle?

I am not totally sure that NGSW will be fielded at all.    But, the stated plan is to field the M7 as a replacement for the M4 in the infantry and some other close combat elements.

Interesting video.

He mentions ~5:30 zone that SIG uses 'Maraging steel' for superior barrel life. Curious what alloy that is and what properties.

https://en.wikipedia.org/wiki/Maraging_steel

Some discussion of it:

https://www.practicalmachinist.com/forum/threads/maraging-steel-for-us-civilians.195118/

Googling Maraging steels, came across this, from the makers of the H&K416's awesome barrels:

https://www.aubertduval.com/wp-media/uploads/2022/01/BD_fiche-petits-calibres_012022.pdf

No idea if this is the alloy, but description seems relevant:

And then this super fancy Italian shotgun also claims to use miraging steel, likely just for the bragging rights.

https://www.bosis.com/shotgun-basis-models/challenger/challenger-technical-detail.html

gatnerd said:

Curious what alloy that is and what properties.

These are very low carbon highly alloyed steels with high strength and ductility after heat treatment.
Maraging means "martensitic" and "aging".
A typical maraging steel is: X 3 NiCoMoTi 18-9-5
Allmost no carbon but lots of Nickel, Molybdenium and Titan

These alloyes are nothing new really. But they are pretty expensive and the required heat treatment could not be done by anyone in the past. This has changed in the last decades so the availability and price got better. Which means its now more commonly used. Its still not common but its also not obscure anymore.