Anyone else heard rumours that only the SIG 6.8x51 mm rifle and automatic rifle are left in the US Army's NGSW competition? Separately, I've heard that US SOCOM is resuming its testing of 6.5x49 mm Creedmoor in both AR and LMG platforms.  

I dont understand sigs logic with the 13 inch barrel. The objective was to give a 600-700m range, and those barrels cant be very intuitive or 'pointable' and long range

If you think that a crazy fast round would preclude the needing of "fancy optics" is because you haven't read or either understand the role of present and near future FCS of NGWS program

What would have been the reason Textron would have lost the competition? I mean, TV is more or less obvious at this point with GD out, but at the same time SiG is making serious efforts in making their civilian version visible. SiG's candidate is the heaviest at cartridge level, the least innovative and it has not any serious growth capabilities. Finally, SiG bimetal case is going to be more expensive than conventional ones.

I mean, if AAI / Textron CT bid would have an actual deal breaker, it should have been known time ago. It would have even precluded its participation and even the entire program. I mean, it would have been a total disconnection between LSAT, NGAD and NGSW that would be really difficult to explain

poliorcetes said:

What would have been the reason Textron would have lost the competition?

NGSW is very similar to ACR, it seems to revolve around risk mitigation.

During the ACR program, you had:

- Colt proposing a derivative of the M16, firing 5.56 mm duplex ammo and regular M855, technically that's a ~0% risk solution,

- AAI proposing a conventional rifle firing a discarding sabot flechette, from a regular 5.56 mm brass case, that's your ~25% risk solution,

- Steyr proposing an unconventional rifle (push-thru) firing a discarding sabot flechette from a plastic case, that's your 50% risk solution,

- HK proposing a very unconventional rifle firing a full caliber bullet, but from a caseless round, that's your 75% risk solution. (100% risk would be a flechette from a caseless round).

For NGSW, you have similar structure, with SIG proposing a "low risk" option, GD proposing the "intermediate version" and Textron the highest possible risk level, but also the highest reward.

That's a good way to run a technical program, avoiding to end with a "no winner" configuration, and avoiding Textron to charge a very high bill for their products.

But as far as I know ACR ended preciselly with no winner. I think that the problem was the same of SALVO / SPIW: increase hit probability (not effects, like NGSW does) using only mechanical/physical element combination and not (unexistant) sensors and software. Indeed, NGSW is a no-go without FCS and from the very beginning it is going to be integrated in broader systems (both next visors - say IVAS or another one - and any future BMS). And what is more important, it is not focused on increasing hit probability (something that is going to be centered on any future FCS), but it pays attention to armor penetration and effective range increase. The last two requisites are much easier to connect to physical properties of the cartridge rather than hit probability

I assume that huge pressure increase is related with armor penetration. Future armor penetration. After a M-nn with M1184 cartridge is fielded, other actors will follow suite and will increase armor protection. Given the state of art, is more feasible to increase protection rather to increase penetration. Therefore, future cartridges and weapons need a growth margin both for decrease tungsten use (maybe machine tool-grade steel?) or for increase penetration capability. If a dual metal case is used, it will need to be reinforced if further pressure is demanded and possibly weight will be increased (although I'm not sure about the latter)

IF case telescoped design is enough mature in all its elements (cartridge itself, cartridge cost reduction, chamber sealing at all the foreseen temperatures, reliable extraction), then the advantages are too clear. And the program chain from LSAT and even before alledgedly have had the effect of mature such set of elements.

I don't know. I don't have all the relevant information nor the technical level to be sure at all, but it seems to me that just renouncing to the use of polimer for case walls is a clear lose. Not only in terms of weight reduction, but on thermal isolation too. Besides, a push-thru design offers a really nice advantage for a MG design, since chamber is disconnected from barrel trunnion except for the firing step

poliorcetes said:

But as far as I know ACR ended preciselly with no winner

ACR ended with no winner because the goal was to increase hit probability - and pretty much every rifle tested actually had worse hit probability then the M16. Ultimately the only thing taken from ACR was the 4X ACOG, which was found to marginally improve hit probability at long distance on the ACR target range.

Complete ACR results:

https://forums.delphiforums.com/autogun/messages/7773/1

And the gist: 

poliorcetes said:

What would have been the reason Textron would have lost the competition? I mean, TV is more or less obvious at this point with GD out, but at the same time SiG is making serious efforts in making their civilian version visible. SiG's candidate is the heaviest at cartridge level, the least innovative and it has not any serious growth capabilities. Finally, SiG bimetal case is going to be more expensive than conventional ones. I mean, if AAI / Textron CT bid would have an actual deal breaker, it should have been known time ago. It would have even precluded its participation and even the entire program. I mean, it would have been a total disconnection between LSAT, NGAD and NGSW that would be really difficult to explain

DISCLAIMER : This is unverified reddit hearsay from a supposed "USAMU Tester", Along with some cross referencing with earlier forum discussion on this topic + the original RFP accuracy standards

However this could provide a plausible explanation for a possible GD/Textron Drop out

Regarding this topic it had been discussed earlier on this forum about a possible drop in accuracy with both TV Neckless and Textron CT type cartridges
In this discussion with EmericD :http://forums.delphiforums.com/autogun/messages/7908/36

When you combine this with the original RFP calling for a certain standard of accuracy

All this together could present a plausible explanation, if indeed CT and TV neckless are inherently 3-4 MOA systems, wheras the goals are 1.7~ MOA accuracy

Interested to hear this forums take on this

Textron claimed their round was more accurate than normal ammo