I Picked Up These 277 Sig Fury Cases At The Range

[Walt Krafft]

75k psi does expand the head so it needs sizing.

 

[jackson1]

What's old is new again. Purchased 5 steel head cases back in the 80's for my 35 Brown Whelen. Their literature spoke of using duplex loads for higher velocities. Never used them and still have a couple.

 

[SKWERLZ]

I wanted to see how it was constructed.

I am not up on all of the latest staging techniques, so I do not know exactly how they put this together with that locking feature.

I also chucked one up and using a sharp tool, took a cut on the steel rim. It is definetally some type of free machining stainless, maybe regular 416.

Just curious.View attachment 1626754

Thanks for the sectioned view!

 

[SKWERLZ]

Aside from not being able to size the steel head down in a conventional die, is there any reason this could not be reloaded?

Maybe a roll sizer would size the base
Would be interesting to know at what pressure the steel base goes plastic?

 

[Steve Donlon]

This seems pointless. The military will not reload these. What will they do to a barrel after a relatively short time. The barrel will be harder to clean and fire cracking will be an issue. I don't think it's a good idea just for more velocity. Am I missing some thing?

 

[WSnyder]

Am I missing some thing?

Probably not. Let's see how the Federal high pressure case works out. One piece case with the claim of reload-ability to come. Barrel life for either high pressure case I assume is going to suffer but many won't care. Suppressor use is increasing greatly and the desire to retain velocity with short barrels will be a yes to many I think even with some potential negatives.

 

[Steve Donlon]

The more I think about the Fury the more I think someone has their hand in the cookie jar. The bullet is to light to be effective for penetration for military use. They can't be concerned with recoil so better to go big. IMO. They say this is for "SPECIAL UNITS". Why not take advantage of this new case and use the AR 10 with a heavy bullet at 2700-2800 fps. And use it as a squad weapon for all soldiers like the BAR was. And keep the AR15 for regular soldiers that will be drafted if we do go to war with Russia or China. That seems to be the reason for the FURY in the first place. I don't think we will go to war with Russia. China will not use guns they will use something far more like a pathogen.

 

[ebb]

The long range elk guys were doing this many years ago. On the old (pre Backus) long range hunting several of the guys posting there were using them. They made a steel, or stainless steel head and threaded the brass to the case head. Daryl Castle is the only name I can remember, before Lapua made the good 338 brass they make today. They talked of using African sized cases but even though they had capacity they were designed for low pressure and lost primer pockets. I tried to get some of there homemade cases for my 300 Jarret, but no one was having it and they had stopped making it by then. I soon learned that high pressure was tough on the rifle, and if stacking tolerances or some factor I had no control over got me in too deep it could be fatal. If you have to have more build a 277 on the 338 Lapua or some other case and run it with in the capability of the action and barrel.

 

[markm87]

Cool pics. Thanks for sharing.

 

[hoz53]

The long range elk guys were doing this many years ago. On the old (pre Backus) long range hunting several of the guys posting there were using them. They made a steel, or stainless steel head and threaded the brass to the case head. Daryl Castle is the only name I can remember, before Lapua made the good 338 brass they make today. They talked of using African sized cases but even though they had capacity they were designed for low pressure and lost primer pockets. I tried to get some of there homemade cases for my 300 Jarret, but no one was having it and they had stopped making it by then. I soon learned that high pressure was tough on the rifle, and if stacking tolerances or some factor I had no control over got me in too deep it could be fatal. If you have to have more build a 277 on the 338 Lapua or some other case and run it with in the capability of the action and barrel.

i saw steel head cases advertised in a PS issue from at least 20 years ago. not much has come of them so far. if we would say these run at 25% higher pressure i wanna see a bolt action designed for 25% higher pressure than wat is out there now. i dont feel the need for the steel head cases in wat i do.
But Wait!!!- if i can get a 257 Wby that shoots 25% faster like mabie 4500 I may want one....
lol

 

[DaveTooley]

i saw steel head cases advertised in a PS issue from at least 20 years ago. not much has come of them so far. if we would say these run at 25% higher pressure i wanna see a bolt action designed for 25% higher pressure than wat is out there now. i dont feel the need for the steel head cases in wat i do.
But Wait!!!- if i can get a 257 Wby that shoots 25% faster like mabie 4500 I may want one....
lol

Going from a .473" chamber to .550" is approximately a 25% increase in bolt thrust. So staying with a .473" chamber at 80k psi is where we are today with the larger magnum cases.

 

[Maximus1840]

I recently purchased a box of these hybrid cases out of curiosity. They are unfired with bullets pulled but primers intact. I'm planning on converting a few to 375 raptor while waiting on my build parts.

 

[ebb]

I am sure I don't see or understand the fascination with a .277 bullet diameter. But could not the same be accomplished with a standard 284 Winchester or 6.5-284 with a well designed tungsten penetrator bullet? I haven't read the latest but some officer has blasted the sig fury and said it's unfit to use in battel. It seems to me it maybe have been too big of a step from standard rifles to the Sig. I do not see my reloads at 80,000 PSI anytime soon. All of the short range BR guys say that the custom actions they use are capable of more pressure than a factory action. I am sure they are right, but what are they rated at? Can they handle 80,000 ?

 

[joshb]

i saw steel head cases advertised in a PS issue from at least 20 years ago. not much has come of them so far. if we would say these run at 25% higher pressure i wanna see a bolt action designed for 25% higher pressure than wat is out there now. i dont feel the need for the steel head cases in wat i do.
But Wait!!!- if i can get a 257 Wby that shoots 25% faster like mabie 4500 I may want one....
lol

They have thrown out the bait and people are biting. Sig is making a “new gun” to handle the new case. Higher speeds are enticing. Marketing at its best! It worked for Hornady. Why not Sig?

 

[hoz53]

They have thrown out the bait and people are biting. Sig is making a “new gun” to handle the new case. Higher speeds are enticing. Marketing at its best! It worked for Hornady. Why not Sig?

you are right about that- its always follow the money. i saw the gun and ammo at a sig booth at an exhibition hall a year to two ago. and wat about the new federal round? It will be interesting to see where it all goes. mabie lots more different cartridges. If i can get 3300 with 105s out of my 6mm Remington Improved mabie ill be able to get 4000 out of the steel head model have to put that in the solver and shake it around. how many currrent bullets can even stand that?

 

[hoz53]

Going from a .473" chamber to .550" is approximately a 25% increase in bolt thrust. So staying with a .473" chamber at 80k psi is where we are today with the larger magnum cases.

thanks for that info Dave

 

[joshb]

“If i can get 3300 with 105s out of my 6mm Remington Improved maybe I’ll be able to get 4000 out of the steel head model.”
You just have to decide if that’s worth buying a new Sig gun and barrel for it.

 

[Webster]

This seems pointless. The military will not reload these. What will they do to a barrel after a relatively short time. The barrel will be harder to clean and fire cracking will be an issue. I don't think it's a good idea just for more velocity. Am I missing some thing?

Sounds like extremely short barrel life at 80,00 PSI. Looks to me like a multi billion dollar project if you rearm all our military. We are stupid enough to pay the bill. What if NATO countries don't want it or cannot afford it.. Then you cannot share ammo between countries during combat. I read somewhere that they estimated that 1.500,000 rounds of 5.56 ammo was fired for each VC killed. 5.56 won't penetrate modern flak jackets. Some kind of hardened steel penetrator should penetrate modern vests.

 

[Catfur]

This seems pointless. The military will not reload these. What will they do to a barrel after a relatively short time. The barrel will be harder to clean and fire cracking will be an issue. I don't think it's a good idea just for more velocity. Am I missing some thing?

Yes, the military wants these for their own purpose. SIG, of course, wants to sell anything they've sunk a bunch of development money into to as wide an audience as possible.

 

[Catfur]

I am sure I don't see or understand the fascination with a .277 bullet diameter. But could not the same be accomplished with a standard 284 Winchester or 6.5-284 with a well designed tungsten penetrator bullet?

The military started with a bullet design they wanted, and then tasked contractors with developing a round and rifle system to fire that bullet.

Modern steel actions (like post Mauser 98) are readily capable of taking 100K PSI (some with shortened lifespan), it's the brass that won't.