Reloading for the new .277 Fury from Sig

[C-130 Dude]

Lot of "wrong" in this thread. Here's some facts:

1) Cartridge is the same whether you call it 6.8x51MM (military) or .277 Fury.

2) 80,000psi IS (and has been for a couple years) the SAAMI approved spec for the round.
a. This pressure requires the three piece composite case (steel case head, brass case body, and locking ring to hold them together.)
b. The all brass cased version of the ammo runs at "normal" pressures.
c. Both are because the weak point at 80,000psi is the casehead and primer pocket in brass.

3) 3,000fps is 135gr bullet (military designed projectile with penetrator) from a 16" barrel.

4) Military set a spec for barrel life of twice the "useful life" of a current M4 barrel. (Which basically means how many rounds sent downrange before the weapon will not shot 4MOA or less.) For an M4, this is ~6,000 rounds. 6.8x51 military barrels use a nitriding process instead of the M4s chrome lining (and some other changes) and have gone ~14,000 rounds before accuracy falls out of required spec. What that means for aftermarket civilian barrels in terms of useful accuracy life is anyone's guess. That said, SIG has stated that all barrels it produces for this round, including for the Cross rifle, are built to the military standard.

5) SIG has stated that the composite case is "currently not reloadable" but that "they are working on it". Issue appears to be how to resize the steel case head without possibly compromising the locking ring. When you consider 80,000psi, failure of the locking ring would be a bad thing.

FYI - All of the above is public knowledge reported by Soldier Systems Daily and others who closely follow the military.

Note: I have no affiliation with SSD or SIG. I'm just ex-Army and a gun nut who has been following this process for years.

The 6.8 and .277 may size out to be the same however, the military 6.8 version is not the same as the Fury .277. The 6.8 is the high pressure version. Not available to the public. Currently. And i might add, is not currently reloadable. As you stated, Sig is working on this. The Sig .277 Fury is the civilian lower power version manufactured by Sig for civilian use. I mention this because some folks may think that they may be able to get their hands on the military 6.8 fired cases to reload.

 

[Coyote Shadow Tracker]

Just a recent news report

The XM5 and 6.8x51 Ammunition Will Be a Decisive Advantage. U.S. Allies Should Adopt It, Too - The Truth About Guns

In yesterday’s press conference announcing SIG SAUER’s victory in the Next Generation Squad Weapon competition, Army officials said America’s likely future adversaries were a key factor in the final choice. The XM5 (a variant of the SIG MCX) and the XM250 machine gun run the recently-developed...

www.thetruthaboutguns.com

Also if you look at Sig's Company information on 6.8 X 51 the hybrid cartridge would be a reloaders (dream) to get to 80,000 PSI.
I am really interested in the technology where Sig is not using the Crome coated Barrels like in the M-4 and going to a "Nitrate" coating to improve the loss of accuracy up to 28,000 fired rounds (what I read).
Just think if we can get Barrels to last more than 2,000 without accuracy loss???

 

[2buffalo]

The 6.8 and .277 may size out to be the same however, the military 6.8 version is not the same as the Fury .277. The 6.8 is the high pressure version. Not available to the public. Currently. And i might add, is not currently reloadable. As you stated, Sig is working on this. The Sig .277 Fury is the civilian lower power version manufactured by Sig for civilian use. I mention this because some folks may think that they may be able to get their hands on the military 6.8 fired cases to reload.

Do you have links to back this up? Everything I have read says the .277 Sig Fury is the same case and same pressure civilian or military version.

 

[Craig Miller]

The ONLY difference between the military 6.8x51mm and the .277 SIG Fury is the projectiles. The military version uses a US Army designed 135gr bullet that is built around a specific armor penetrator. That bullet is not expected to be available to civilians. The case, pressures, etc. are all the same.

 

[jpfrog]

The ONLY difference between the military 6.8x51mm and the .277 SIG Fury is the projectiles. The military version uses a US Army designed 135gr bullet that is built around a specific armor penetrator. That bullet is not expected to be available to civilians. The case, pressures, etc. are all the same.

Yeah, no. You'll want to check your sources. Mil version uses a three piece hybrid case, as has been referenced many times in this thread and achieves pressure of 80k psi. Civ version is all brass one piece case in the 60-65k psi range. And the powder used by Sig for the Mil version is proprietary to allow them to achieve those pressures of 80k.

 

[2buffalo]

Yeah, no. You'll want to check your sources. Mil version uses a three piece hybrid case, as has been referenced many times in this thread and achieves pressure of 80k psi. Civ version is all brass one piece case in the 60-65k psi range. And the powder used by Sig for the Mil version is proprietary to allow them to achieve those pressures of 80k.

Can you post an actual source for this? When I bought my Cross all the Sig write ups said it was specifically developed for the 277 sig fury. The bolt was made to withstand the 80k psi loads and the hybrid case. I bought it in the 308 because the fury wasn't available yet and I was going to switch it over when the 277 parts were available.

An Official Journal Of The NRA | 277 SIG Fury: An Inside Look

To meet military needs, SIG Sauer had to come up with a revolutionary new cartridge design. The company succeeded with the release of its 277 SIG Fury.

www.americanrifleman.org

 

[C-130 Dude]

Just a recent news report

The XM5 and 6.8x51 Ammunition Will Be a Decisive Advantage. U.S. Allies Should Adopt It, Too - The Truth About Guns

In yesterday’s press conference announcing SIG SAUER’s victory in the Next Generation Squad Weapon competition, Army officials said America’s likely future adversaries were a key factor in the final choice. The XM5 (a variant of the SIG MCX) and the XM250 machine gun run the recently-developed...

www.thetruthaboutguns.com

Also if you look at Sig's Company information on 6.8 X 51 the hybrid cartridge would be a reloaders (dream) to get to 80,000 PSI.
I am really interested in the technology where Sig is not using the Crome coated Barrels like in the M-4 and going to a "Nitrate" coating to improve the loss of accuracy up to 28,000 fired rounds (what I read).
Just think if we can get Barrels to last more than 2,000 without accuracy loss???

Serious round counts. We'll see.

 

[2buffalo]

277 SIG FURY, 150GR HYBRID HUNTER

Featuring NOSLER Accubond Bonded Core Bullets.

www.sigsauer.com

 

[Craig Miller]

Yeah, no. You'll want to check your sources. Mil version uses a three piece hybrid case, as has been referenced many times in this thread and achieves pressure of 80k psi. Civ version is all brass one piece case in the 60-65k psi range. And the powder used by Sig for the Mil version is proprietary to allow them to achieve those pressures of 80k.

Please stop saying things that are demonstrably wrong. Please see the link in post #64 (directly above) for the civilian three piece case.

Powder in the military loading is possibly proprietary to the military but that has nothing to do with the ability to reach 80k psi.

SIG also sells an all brass case version with a 135gr regular FMJ bullet (not a penetrator) that is a training round.

 

[jpfrog]

Can you post an actual source for this? When I bought my Cross all the Sig write ups said it was specifically developed for the 277 sig fury. The bolt was made to withstand the 80k psi loads and the hybrid case. I bought it in the 308 because the fury wasn't available yet and I was going to switch it over when the 277 parts were available.

An Official Journal Of The NRA | 277 SIG Fury: An Inside Look

To meet military needs, SIG Sauer had to come up with a revolutionary new cartridge design. The company succeeded with the release of its 277 SIG Fury.

www.americanrifleman.org

I did, in post #39. (https://www.longrangehunting.com/threads/reloading-for-the-new-277-fury-from-sig.301206/post-2512939)

You can also look at this (https://www.gunsandammo.com/editorial/277-sig-fury-cartridge/457153), as one example, I'm not going to give you a full Google summary, but a quick search yields dozens of results. Below are some excerpts from it:

"No matter how often anyone states their action is "strong enough", never shoot the .277 SIG Fury in a rifle that wasn't expressly designed for high-pressure ammunition. At the time of this writing, the only rifle designed for this pressure level is SIG Sauer's Cross new MCX-SPEAR.;"

"Knowing that the SAAMI committee had debated whether to approve the .277 SIG Fury cartridge, they obviously reached an acceptable compromise. Each box of ammunition comes with a large warning printed so that those of us tempted to re-barrel grandad's deer rifle will know in advance that 80,000 psi will destroy "Old Faithful" in short order."

Please stop saying things that are demonstrably wrong. Please see post #64 for the civilian three piece case.

SIG also sells an all brass case version with a 135gr regular FMJ bullet (not a penetrator) that is a training round.

Demonstrably wrong my rear. I've sited 2 articles where it says don't do it in your rifle unless you SPECIFICALLY bought a Sig that was built to withstand the pressure. What have you sited? Sig sells ammo that can only be used (currently) by a Sig rifle. They don't sell brass by itself, yet. Both articles I sited mention that, because they are focused on the govt. contract first. I'm being polite because I see you're from Texas, so you have that going for you.

 

[2buffalo]

I did, in post #39. (https://www.longrangehunting.com/threads/reloading-for-the-new-277-fury-from-sig.301206/post-2512939)

You can also look at this (https://www.gunsandammo.com/editorial/277-sig-fury-cartridge/457153), as one example, I'm not going to give you a full Google summary, but a quick search yields dozens of results. Below are some excerpts from it:

"No matter how often anyone states their action is "strong enough", never shoot the .277 SIG Fury in a rifle that wasn't expressly designed for high-pressure ammunition. At the time of this writing, the only rifle designed for this pressure level is SIG Sauer's Cross new MCX-SPEAR.;"

"Knowing that the SAAMI committee had debated whether to approve the .277 SIG Fury cartridge, they obviously reached an acceptable compromise. Each box of ammunition comes with a large warning printed so that those of us tempted to re-barrel grandad's deer rifle will know in advance that 80,000 psi will destroy "Old Faithful" in short order."


Demonstrably wrong my rear. I've sited 2 articles where it says don't do it in your rifle unless you SPECIFICALLY bought a Sig that was built to withstand the pressure. What have you sited? Sig sells ammo that can only be used (currently) by a Sig rifle. They don't sell brass by itself, yet. Both articles I sited mention that, because they are focused on the govt. contract first. I'm being polite because I see you're from Texas, so you have that going for you.

Quoting you: "Mil version uses a three piece hybrid case, as has been referenced many times in this thread and achieves pressure of 80k psi. Civ version is all brass one piece case in the 60-65k psi range."
This statement is incorrect based on the article you are citing:
Knowing that the SAAMI committee had debated whether to approve the .277 SIG Fury cartridge, they obviously reached an acceptable compromise. Each box of ammunition comes with a large warning printed so that those of us tempted to re-barrel grandad's deer rifle will know in advance that 80,000 psi will destroy "Old Faithful" in short order."
So this means that it will be available to civilians....

Also: No matter how often anyone states their action is "strong enough", never shoot the .277 SIG Fury in a rifle that wasn't expressly designed for high-pressure ammunition. At the time of this writing, the only rifle designed for this pressure level is SIG Sauer's Cross new MCX-SPEAR.;"

This is false because the Cross was deigned around the 277 fury. Call Sig and they will straighten it out for you.

 

[2buffalo]

Can't believe I haven't seen the popcorn eating antelope yet....

 

[jpfrog]

Quoting you: "Mil version uses a three piece hybrid case, as has been referenced many times in this thread and achieves pressure of 80k psi. Civ version is all brass one piece case in the 60-65k psi range."
This statement is incorrect based on the article you are citing:
Knowing that the SAAMI committee had debated whether to approve the .277 SIG Fury cartridge, they obviously reached an acceptable compromise. Each box of ammunition comes with a large warning printed so that those of us tempted to re-barrel grandad's deer rifle will know in advance that 80,000 psi will destroy "Old Faithful" in short order."
So this means that it will be available to civilians....

Also: No matter how often anyone states their action is "strong enough", never shoot the .277 SIG Fury in a rifle that wasn't expressly designed for high-pressure ammunition. At the time of this writing, the only rifle designed for this pressure level is SIG Sauer's Cross new MCX-SPEAR.;"

This is false because the Cross was deigned around the 277 fury. Call Sig and they will straighten it out for you.

Yeah, the original article from a couple years ago as well as the ones others have posted on here suggested that there would be 2 versions of the ammo, and possibly brass components, for Mil/Civ. The fact that they have now decided to make the 80k psi avialable to Civ is new, and they still may make separate all brass cases at the normal SAAMI pressure ranges in the 60k area.

However, the direct quote from Sig in the 2nd article you reference from my post is not wrong. It's a direct quote. The Sig Cross is made by Sig to withstand the pressures of the 277 (80k psi), you said so yourself, and so did they, which I quoted. Therefore, the Sig made rifle is the exception, not the rule. This ammo should NOT, per Sig, be fired from a rifle not intentionally built to withstand those pressures. In other words, don't rebarrel your Remington 700 for this round. I don't need to call Sig, they already provided the quote.

 

[jpfrog]

Can't believe I haven't seen the popcorn eating antelope yet....

Now that is funny, and I'm sure @FEENIX is already a bag or two into his evening, along with a whiskey.