EmericD said:

I just thought about bullets and sabot, I think I have an idea to significantly reduce the cost of this kind of ammo. I will send you an e-mail next week. Unfortunately, I still have no idea on how to avoid sabot slippage and in-bore yaw...

Interesting. I'll be excited to read that.

I just followed "best practices" for the APDS tank ammunition of yore. That means I kept the sabot bearing surface well ahead of the CoG, and I used another little trick to keep the projectile locked in rotation.

"Quintus O:  ... And, likewise, I think TV's ammunition is the betting horse here, at least from a technology standpoint. Textron seems to have had the most favor politically from the outset. "

Textron does seem to be rather good at playing "The Game"...

The Textron/AAI/UIC, whatever they feel like calling themselves this time around has been involved in US smallarms development since Project salvo and SPIW programs in the 1960's. In fact one would be hard pressed to find a US small arms program they were not a part of on some level. As AAi they took part in the Future Rifle program begun in 69'. In 86 they were naturally part of the ACR program. At LSAT startup in 2004 they were there. And now as Textron for the NGSW.

Hundreds of millions have been poured into these programs over the years. With no doubt a few tens of millions going Textron/AAI/UIC's way. But they are playing the game, not making the rules. In all the various small arms programs not a single rifle designed by anyone has taken the field.

Mostly, I attribute that to two things:

1:  The military never really having a clear plan about what they actually want. (sometimes asking for conflicting requirements)

2:  And the industry/institutional investment in the 5.56/AR15 platform. Lots of politics...

Don't forget that ARES is also a subcontractor for Textron, and they had Eugene Stoner working on CT in the 1980s.

https://soldiersystems.net/2020/10/26/true-velocity-ammunition-advances-to-shortlist-for-australian-land-159-force-modernization-program/

GARLAND, TX (October 26, 2020) – Australia-based NIOA, a company specializing in the supply and sustainment of weapons and munition systems to the Australian Defense Force (ADF), has invited Texas-based True Velocity to the next stage in the LAND 159 Lethality Systems Project procurement process. The LAND 159 project will equip the men and women of the ADF with next-generation pistols, assault rifles, machine guns, sniper rifles, direct fire support weapons, and ammunition. True Velocity, which manufactures composite cased ammunition for military, law enforcement and civilian use, will specifically participate in the narrowed search for next generation ammunition solutions.

May our Australian friends benefit from production overruns if this gets adopted!

Well TV has now released their 5.56 polymer case onto the civilian market, so we will get see whether it has reached a level of technical maturity for potential military use.

https://www.thefirearmblog.com/blog/2023/07/21/composite-cased-5-56-true-velocity/

To my continued annoyance, they market their cases as lightweight, yet don't publish the cartridge weight in their advertising....

I want to get some, but at $1.25 per round, not much. If they sold their 77-grain cartridge for that, though..

farmplinker2 said:

want to get some, but at $1.25 per round, not much. If they sold their 77-grain cartridge for that, though

Yes their prices are quite high; while I know they need to recoup their investment, those prices for non-reloadable ammo that no one knows how will perform I think will really stymie their market penetration. Probably would have been better to release it cheap then slowly raise prices. 

i recall that a prototye polymer 556 weight 7.5 grams

Given today's prices they are ideally positioned to break into the market something that would have been impossible pre COVID when the price point for .223 has been much much lower.

There is bunch of 1.2+$ ammo on the market now days

https://www.midwayusa.com/556x45mm-nato/br?cid=21887