>>64101637
Shit.
>>64101658
>Stellite
That's good news.
Cost is honestly no object as long as its demonstrably possible, we already use lots of exotic materials. The Army pays something like $10k for each XM157, so it's not like they aren't willing to spend on small arms. You just need a particularly sleazy salesperson.
>really hard to shape
Yeah, that's how it usually goes. They consistently figure it out though, and economies of scale take over from there.

>Is there a catch?
One anon here says a round bent and exploded during firing in the testing phase of NGSW, but that's probably an easy fix. Textron called their polymer 'medical grade', so it was likely a commercial formulation.
The walls aren't much thicker than brass really.
>Or is 100kpsi really just a matter of enveloping the *entire* cartridge in the chamber with no bit left unsupported?
That's exactly right. The curved surface of the chamber is a monolithic cylinder, which rises to meet the 'bolt face' with the firing pin. There is no ejector. This is conjecture, but you might be able to increase pressure ratings even further with electronic firing, which was one of Textron's suggestions early on.
>Could a cased telescoped cartridge also work with brass or steel?
No doubt. They might not transfer the forces to the chamber as well (they probably won't have to), and they won't provide the heat management advantages of polymer. The technology is generally better suited for caseless and polymer case and the pressure thing is incidental. You could probably get even higher pressures with metallic cases if you could find a use for it.