Sig Hybrid 5.56 cases. Who's got info?

[357Max]

Who's got any info on this. Looks like Sig is going head to head with the NAS 3 Shell Shock cases.
From a reloading standpoint I'm interested in these cases.

Never drank the 25-45 Sharps Cool aid, but with these hybrid cases that seems more interesting.

 

[bfoosh006]

All I have seen, so far ...
https://www.ar15.com/forums/ar-15/R...ned-for-High-Pressure-80kpsi-5-56/118-791849/

https://www.ar15.com/forums/general...-from-mk18-than-M995-out-of-an-M4-/5-2819019/

 

[supercorndogs]

I see some guys reloading the sig cases having trouble with leaking at the case head junction and etching chambers.

 

[357Max]

I see some guys reloading the sig cases having trouble with leaking at the case head junction and etching chambers.

That’s on the 277 cases and it’s an overblown issue in my opinion. I just ran a 3 day match with those 277 hybrids sized to 6.5C. I can see Were the steel portion resides in the chamber, but can’t feel any knd of step with a pick or anything. It may be more of a problem with full 80k psi loads in the Fury.

 

[putput30]

I like the NAS3 cases running normal to slightly elevated pressures but taking advantage increased case capacity for more velocity or a single piece case like the peak alloy cases if im going to run 80K+ psi to avoid the plasma jet cutting my chamber up. I do know sig made 308, 6.5, 556, and I believe a 338 norma hybrid cases. Not sure if the juice is worth the squeeze pushing 80k+ psi in terms of weapon durability/longevity. Also the risk of kabooms with legacy platforms has to be a concern.

 

[supercorndogs]

How much extra case capacity?

 

[putput30]

How much extra case capacity?

Not sure of the sig cases but the NAS3 cases are usually in the 8-10% range.