In terms of Armor penetration, I came across some data in regards to exposed tip tungsten AP, which may be what we see used for the ADVAP projectile. 

This projectile was originally developed by Silver State Armory, and now is taken over by a spin off company of SSA after they were purchased by Nosler.

https://defensereview.com/silver-state-armory-sabot-light-armor-penetrator-ssa-slap-armor-piercing-ap-rounds-in-5-56mm-nato-223-rem-7-62mm-nato-308-win-and-6-8-spc-6-8x43mm-spc-tungsten-carbide-core-rifle-ammo-for/

Its described as 'saboted' but really its just a HVAP style round where most of the projectile is tungsten, with a little brass skirt at the base for engaging the rifling. The design goal per defense review was that they outperform M993/M995.

https://modernarmsinternational.com/shop/143gr-ap/

This is interesting in a couple regards:

-It shows that going to exposed tip tungsten does offer better performance then M993

-It shows that defeating Level IV is much more difficult then defeating 1/2" of AR500 steel; can pierce 0.5" steel at 2x the range of Level IV. 

-It shows even .338 Lapua exposed tip tungsten would not have met the original 600m AP goal of the NGSW:

I have a renewed doubt about gas sealing

https://twitter.com/i/status/1398184454795845632

https://twitter.com/xmszeon/status/1398184454795845632?s=20

I cannot embed twitter video again, sorry. Look at the html source of my post.

My doubt is: tilting chamber is going to be inserted into a receiver recess

Plastic cap advances and produces the seal while there is pressure, right?

how is friction between chamber and barrel avoided when feeding is started? is plastic cap seal dependant of gas pressure?

Lets see if this works:

Whoever VPNtest is, he's an incredibly talented graphic artist and engineer, and has a gift for bringing dry patents to life. 

Up until just now, I hadn't realized that the CT case sort of 'blows forward' to seal the chamber.

GD is officially out of NGSW, LoneStar Future Weapons is now the prime contractor.

https://soldiersystems.net/2021/09/01/us-army-grants-ngsw-novation-from-general-dynamics-ots-inc-to-lonestar-future-weapons/

I can only interpret this as leveraging NGSW participation to launch products into the civilian market; an SME cannot possibly win as prime for a program this big, even if they weren’t pitching a bullpup.

Yes, I think your analysis is spot on - without GD+Beretta, its hard to imagine a unknown company like 'lonestar future weapons' is going to win the contract. 

Not to mention that in addition to the bullpup, they don't have a real LMG, just that slightly longer barrel version of their bullpup as an Automatic Rifle. 

Then the problem is if CT technology is fully mature and if NGSW requisites are actually fieldable or not.

I could not understand how SiG technology would hace even slight opportunities of winning the program. More expensive cartridges than brass just for updating existing weapon designs.

Now the next step could be if .338 Norma-ish is going to be adopted. I neither could understand that such a system would be adopted using brass cartridges or cartridges of a different technology than NGSW one

Strikes me that the CT ammo could be loaded with unusual projectiles, such as multiplex or apds...is that likely do u think

Yes, but also no.

That is to say, it’s probably technically possible but very unlikely.

Duplex rounds have never really caught on despite being tried many times. The compromises in projectile design necessary to fit 2 in the cartridge are, I suspect, too significant to accept.

APDS has its own problems in small arms which have been touched on in this thread and others. I believe that ATK examined APDS during CT development and rejected it due to excessive parasitic mass.

Well the 6.8 is  good caliber for the sabot so surely a 4.8mm steel rod could be launched with about 2400lbs of energy, and it penetrates well enough that u dont need tungsten.

Could textron have used 2 or 3 rotatig chambers, to keep the barrel cooler on their SAW...or does it only keep the chambers cooler

Just keeps the chambers cooler.