SIG Sauer HYP, AR10 in .277 Fury

I am interested in the .277 Fury chambering in a LFAR, more then the SIG aspect.

80K is a heck of a PSI for a LFAR. I understand about the case design being stronger. I'd like to see what SIG did to the gas system to allow it to function.

I noticed the 3 gas ports on the carrier, but If memory serves me that didn't amount to much when comparing a Armalite v. DPMS bolt carrier in 6.5CM or .308.

Anyone know what the port pressure / gas pressure curve looks like for the .277 Fury ?

Is the bolt "harder" / stronger ?

Heck, why didn't the US consider a LFAR over the SIG Spear Fury ? ... if the "LFAR can handle it"
 
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So could the p320…
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I would love to know the details of the whole gas system, gas port size, bolt specs, etc... basically all of how the .277 is "allowed" to run in a LFAR.

If SIG would sell the HVP , with .308 and 6.5 CM uppers as an option , then I might be interested in the .277 upper / rifle.

A "set" of all 3 different calibers seems ( to me at least ) to be a attractive option. .277 Fury when I am feeling "rich" , 6.5CM for the benefits ballistically wise, .308 for the surplus / utilitarian aspect.

Hopefully, SIG will see the advantage of the modularity and flexibility of such a system.
 
I wonder if their bolts and barrel extensions are dimensionally proprietary as to reject mixing of bolts not rated for that pressure/bolt thrust.
The video did mention the taper of the bolt lugs which l'm assuming would require a proprietary extension. But going off of what they did with the Spear LT line (it's not a normal AR barrel extension, at least on the 300BO models) I can't see the HYP bolt and extension as being anything BUT proprietary dimensionally. I mean it is Sig. Leave it to them to make a "pattern" DI rifle proprietary.

First thing I said while watching the video is there will be zero aftermarket barrel offerings. I've been trying forever and a day to get someone to make a 1:7 twist 300 blackout barrel for my LT so I can get rid of the stupid 1:5 twist crap. It isn't the barrel that's the issue, it's the extension. No one will touch it.
 
I'm not sure that tapered lugs alone would require a proprietary barrel extension. Here's an older S7 steel .308/6.5 bolt from SRC which has tapered lugs and fits standard large frame barrel extensions. I do think that it will be proprietary and non-interchangeable, though.

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I could be wrong but in the description given by the Sig employee (and he could be wrong) it sounded like the back side of the lug was tapered as it met the main part of the bolt. It's at about the 3:45 mark and the way he "air draws" the taper or rounded corner is why I thought it was the back side of the bolt.

But if it's the front side that's tapered, you may be right which would give Sig the chance to really f8ck things up again. 💀

Here's the LT's extension which is quite a bit longer. I've not seen an exploded view or photos of their DI guns to see how similar or different they are from other AR pattern rifles.
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Pics of a MCX / Spear bolt with "Tapered" lugs... ( 7.62x39 version )

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Note the rounded lugs , which uses a rounded lug lockup in the extension.
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5.56 / 300BK
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Not knowing what the Firing Pin Latch on the MCX was...

"Sig Sauer MCX Firing Pin Latch, Semi. Manufactured from quality steel, this firing pin latch is designed for the Sig Sauer MCX semi-automatic rifle. The firing pin latch holds the firing pin back into the bolt while the bolt is not in battery. Keep your rifle in top operational condition with this factory original component."

Interesting to Note, there is a "G" model for use in a MCX for Geissele triggers.

I have no idea if that would "apply" to the HYP

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