Regarding the service life of the platform, I believe all of that is specified before prototypes are submitted for the trials. Apparently Sig figured out a way to meet the spec.
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Regarding the service life of the platform, I believe all of that is specified before prototypes are submitted for the trials. Apparently Sig figured out a way to meet the spec.
Warning: I know Judo. If you force me to prove it I'll shoot you.
7mm08 if fed that case construction and 82,000 psi worth of faster powder could pick up a few hundred fps velocity.
I know because I have done it before, yes, back in my balls to the walls days. Back when 7.65 NATO brass was dirt cheap and you could afford to load it up to case stretch levels and then throw it away.
Cases always fail before actions do.
Your gun was proofed at 82,000 psi so you know the action is good at that level of pressure. Normal working pressure of 7mm-08 is 62,000 psi.
Last edited by Oldfeller; 04-24-2022 at 06:53 AM.
All retired now, just growing tomatoes and building and shooting my guns.
Firing a 80,000 PSI proof round every time should work well.
That 62,500 psi is the SAAMI MAP for the 7-08. "Normal" psi of factory ammunition will be 2 - 5,000 psi lower. However, "premium" factory ammunition or LR ammunition can approach or be at the SAAMI MAP.Originally Posted by Oldfeller
"Service life", these days, of a rifle action has a different meaning to the military than to civilians.
Larry Gibson
“Deficient observation is merely a form of ignorance and responsible for the many morbid notions and foolish ideas prevailing.”
― Nikola Tesla
I was referring to the caliber. YOU brought up ammo (which is govern by The Hague Accords of 1899). I never said anything about ammo.
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When you are in a hole it's best to stop digging.
You claimed NATO approval was required for the US military to adopt a new cartridge. That is 100% BS.
At some point this cartridge may become a NATO standard but at this point only the Army is adopting it. The contact is for up to 225,000 over the next ten years. Other branches may or may not get on board.
https://www.govconwire.com/2022/04/s...tion-contract/
Hague Conventions of 1899 and 1907 eliminate the use of easily expanding projectiles by its signotors.
Last edited by M-Tecs; 04-25-2022 at 12:17 AM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
You guys enjoy this back and forth sort of disagreement. So agree to disagree, already.
Yes, we have all watched the US military trying to get a better cartridge for our military's carry rifle for over a decade now, and now they have finalized on one and put out a purchase contract.
Is it the ultimate very best one? Likely not, but it is what they have picked. The ARM field trials start now using this one, so let's see how it shakes out in the hands of troops.
Like the .308 Nato round did to the 30-06, it indicates a wind shift is coming for the US arms industry.
I find that once fired brass has gotten RIGHT EXPENSIVE lately, mostly due to the brass price. I see commercial plastic walled cases being sold publicaly today, with some steel walled cases being available as well.
With the cost of copper and brass being so high, I look to see some more steel and plastic walled cases become more common.
There is no law saying they have to be Berdan primed either .......
Last edited by Oldfeller; 04-25-2022 at 07:47 AM.
All retired now, just growing tomatoes and building and shooting my guns.
It is interesting that a new cartridge comes out and military's start looking at it to see if it is applicable to be used in their countries armed forces.
Look how long the 6.5 Grendel has been out and now Serbia is adapting it in their AK series of rifles. A great cartridge to be sure and one of my favorites for long range shooting.
So we,the USA, for more monitory reasons forgo the 6.5 Grendel and look at the 6.8 cartridge for awhile. Now the .277 Fury is going to be used?
In the past the Britt "7 m/m" cartridge for the FAL / L1A1 rifle was tested and had very good attributes but the " not-made-here" mentality kicked in and we went with the 7.62x51mm.
Now were back to a similar cartridge that the Wildcatters have been playing with for a long time now with stronger case components. Got to love it.
Follow the money trail.
You got it, super nato ammo guy.
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If by "tested at" you are referring to proof loads are you suggesting something like an AR is suitable for a constant diet of proof loads? If so I'll watch while you shoot it!
Well as I roll over in the early morning by the campfire my flintlock will still be there.
But Bully for SIG !
"Come unto Me, all you who labor and are heavy burdened, and I will give you rest." Matthew 11:28
Male Guanaco out in dry lakebed at 10,800 feet south of Arequipa.
In the days when the 80 grain Seirra was the only option for 5.56 for 600 and 1,000 yard competition the Army Marksmanship Unit developed a load they called the V-8 load. They had to use harder virgin LC brass and (if I remember correctly) it need to be crimped and sealed primers also. Actual pressure testing showed the load was in the 77K to 78K pressure range. And yes they shot it repeatedly and in competition in the M16's. Per the AMU guys that shot it a lot they would just swamp out bolts when they broke a lug. I was not a AMU member but I did compete with them. I did inspect the brass after they fired it and the primer pockets were toast after the first firing. I was given a small quantity of loaded ammo that I did shoot.
In one of Glen Zediker AR books he goes into more detail about the load and it's actual tested pressure.
Once better bullets hit the seen the V-8 load was no longer used.
I am not suggesting the average person use anything outside of SAAMI specs but that does not change the fact that the AMU did opt to use a very high pressures load that required brass not available to the public and they deemed breaking lugs an acceptable cost of doing business.
With the advent of the 80K cartridges and firearms designed to handle these pressures we should see a technological jump. We already have seen the two-piece cases with harder heads. What I am most interested in is barrel material. Pressure equals heat. Heat/pressure shortens barrel life. My guess is barrels are being made from something other than the standard barrel material since they are full auto. Same for the suppressors.
The 460 S&W is a 65K round. Thirty years ago stating that 65K pressures in a revolver would become reality would have made you the laughing stock of the gun world. The 460 has been around since 2005.
Interesting read here https://www.shootingtimes.com/editor...tridges/371443
So-Called Pressure Signs
Another common belief involves so-called pressure signs, where fired cases (or the rifle) show indications of distress with increasing powder charges. The signs include stiff bolt lift, loose primer pockets, “excessively” flattened primers, and ejector-hole marks on the case head. If none of these signs appear, the load is supposedly safe in the rifle. Unfortunately, they can all occur long before pressures reach normal levels and sometimes fail to appear even when pressures are way over normal.
Before examining each pressure sign, let’s define normal pressures. SAAMI establishes pressures for commercial cartridges made in the United States along with case and chamber dimensions. The maximum average pressure (MAP) allowed by SAAMI for any rifle cartridge is 65,000 psi, yet many handloads won’t show any pressure signs at 70,000 psi and occasionally 75,000 psi. .................................................. .................................................. .................................................. .................................................. .................................................. ...........In the 1990s a major ammunition company decided to commercially legitimize a popular wildcat. Like most wildcats, the cartridge had been developed by using traditional pressure signs and had been around long enough for several popular handloads to be widely publicized. When the ammo company tested those handloads, however, they averaged around 70,000 psi and a few hit 75,000 psi. That’s why factory ammo for the round averaged over 200 fps slower than its popular handloads.
That mirrors personal experience. I load for a lot of cartridges that are per SAAMI are 65K. I have no accurate method to measure pressure so I mostly use primer pocket life. If the primer pocket is loose after a couple loads my guess is the pressure is well above 65K. Generally I like to get a minimum of 10 loadings but when pushing 155's hard in a 308 for Palma one of my best loads would only last 3 loadings.
On a side note lots of the Palma actions don't have ejectors to limit brass flow into the ejector cutout and yes these loads are well over SAAMI. For Palma I used Barnard and RPA action and none of them have an ejector.
The standard 270 Winchester is a 65K cartridge introduced in 1925. A 15K pressure increase in just under 100 years is very slow progress.
The extreme long-range shooters and action builders are playing at well above 65K in a lot of configurations. Those pressures are not as new or as radical as some seem to believe. My only real surprise is that it took almost a hundred years for higher pressure class of cartridge to be introduced.
Some have claimed it will never happen but the contract with Sig indicates it will. The contract is for 10 years. Sauer has won a potential 10-year, $4.5 billion contract from the U.S. Army to produce two Next Generation Squad Weapon variants with a common 6.8 millimeter ammunition and fire control system. And yes this is all without the approval from NATO........
https://www.govconwire.com/2022/04/s...tion-contract/
https://www.army.mil/article/255827/...eapon_contract
Last edited by M-Tecs; 04-27-2022 at 05:26 AM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
Will take some learning on the shooters part, i think.The XM5 and XM250 will be paired with the XM157 Fire Control, a ruggedized advanced fire control system that increases accuracy and lethality for the close combat force. The XM157 integrates a number of advanced technologies, including a variable magnification optic (1X8), backup etched reticle, laser rangefinder, ballistic calculator, atmospheric sensor suite, compass, Intra-Soldier Wireless, visible and infrared aiming lasers, and a digital display overlay. It is produced by Sheltered Wings Inc. d/b/a Vortex Optics, Barneveld, Wisconsin.
Once learned it will be an game changing sight system. https://bulletin.accurateshooter.com/tag/xm157/
The US has owned the night due to night vision. This system should do the same during the day. It may or may not change the poke and spray close range combat actions much but for medium to long range combat the US war fighter becomes much more lethal. The Intra-Soldier Wireless, visible and infrared aiming lasers, and a digital display overlay could be a game changer for close combat? Time will tell as more details come out.
Last edited by M-Tecs; 04-27-2022 at 05:22 AM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
Regarding NATO approval, I suspect the dog will wag the tail. At a NATO conference who is the "dog" in the room at this point?
As for AMU, I'm a fan of AMU and the Marine counterpart and their innovations and accomplishments. However, what they do does not always signify. They could compete with ammunition which would render a rifle unsafe for use after one match and justify the cost because the taxpayers are paying for it all. Because the AMU did it does not mean it is wise for us to follow suit. In fact, if they broke locking lugs they were already beyond strength capability designed into the firearm. That they didn't blow up rifles is due to the strength safety factor designed into the rifle
Anyone who wants to do that can have at it but I'll pass. There is little margin for error left at that point.
Wonder what throat erosion/barrel wear will be like at that pressure/heat level, particularly in SAW type weapons. Even rapid fire in a rifle will heat a barrel very quickly. The old M1 will heat the barrel to a point you will burn yourself on the exposed section of barrel after only one clip, can't imagine the heating after a 30 round magazine rapid fire. Would not want to be the guy in the ejection pattern of spent brass.
This thought occured tome while searching the web on a different tppic: what effect is a study diet of 80 kpsi rounds likely to have on throat erosion/barrel life? Not that that matters to the military funded by our wallets.
I am reminded of the huge Krupp railway guns of WWII. Projectiles were made progressively larger to compensate for barrel wear and were fired in order.
I know I know! That is extreme in relation to this discussion but some current cartridges loaded to "normal" pressures with the best barrel steels have barrel-life round counts in the hundreds. What happens when pressure is increased by nearly a third? In the 7.62 M60 era "A" spare barrel was carried due to relatively short barrel life. How long will a m240 barrel last at 80 kpsi and how many spares will be needed or do I just have an over-active imagination? I do know that contrary to what movies show automayic weapon barrel life is pretty short in sustained-fire situtations.
Last edited by DonHowe; 04-28-2022 at 11:30 AM.
Normally technology improves over time. I expect the same here. 65K cartridges have been around for close to a hundred years. This is from another site and I don't know how accurate it is. That being said I did speak to a Sig Rep that did state barrel life would be more than double of conventional barrels on the CROSS Rifles with the 277 Fury chambering. That was about 6 months ago.
" 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."
From what I have read that 14K includes FA fire? Some claims are with slow fire that doubles to 28,000 rounds???? Time will tell.
I don't know what the real numbers are but I do know barrel life was a design and contract requirement. Same for the suppressors. The claims are the 4.5 billion dollar contract is firm but it has yearly renewals that can switch to other venders than Sig if they don't make good on the requirements.
Last edited by M-Tecs; 05-11-2022 at 04:25 PM.
2nd Amendment of the U.S. Constitution. - "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
"Before you argue with someone, ask yourself, is that person even mentally mature enough to grasp the concept of different perspectives? Because if not, there’s absolutely no point."
– Amber Veal
"The Highest form of ignorance is when your reject something you don't know anything about".
- Wayne Dyer
All out of a 16 inch barrel? The US will drown in the hearing-loss claims.
Anyone going to the Sig Shoot the weekend after next?
Mal
Mal Paso means Bad Pass, just so you know.
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