NGSW Rifle (M4 Replacement) and Machine Gun

Colonial-Marine said:
Weren't they saying they had improved the manufacturing process for the hybrid-case design since the first iterations of it? That seems like a ridiculously high figure per cartridge unless the bullet has a tungsten core or it's something else that isn't standard issue ball/tracer.
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The case itself has 3 parts, Stainless steel case head, brass case body, and a lockwasher between the two. So there's a whole assembly step that has to happen to those stupid things before you can load the casing.

All of which adds costs.

But yes, the extreme pressure round is for busting the Russian dreadnought body armor. So it's probably tungsten core if not DU. And frankly tungsten is the more expensive option there, since DU is a waste product from reactor fuel.


Colonial-Marine said:
Regardless of what happens with that, I still think it's worthwhile to continue investing in development work on the cased-telescoped ammo and small arms designs to utilize it. The True Velocity ammo has some potential but from what I read wasn't suitable for the unusually high pressures NGSW requirements sort-of necessitated.
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The only reason SIG had ludicrous pressures is because their rifle design needed a 13" barrel to come under the length limit with the suppressor on.

The bullpup rifle worked just fine at regular pressures, because its barrel was some 18-22" long (I forget the exact spec, want to say 20"). And the spec for the cartridge was fundamentally 140gr at 3000fps, which is .270 Winchester loads. If you can use 1950s powders to get a 150gr bullet at 2800fps out of 7.62x51 instead of x63, you can do the same thing with a .277 bullet instead.

I really hope Truevelocity can get their ammo out into the world as a more standard thing. Especially practice ammo stuff, where you want it to be as cheap as possible.

There used to be some pure-polymer shotgun ammo out there in the early 2000s, not sure whatever happened to them. Probably low number of reloading times. But they sponsored a lot of various shotgun competitions back in the day, and each loading type was color-coded on the casing (1oz of #6 shot was red, 1oz of #8 was green, etc. Think I'm right on the colors.). You'd just shovel all the empties into the appropriate color box at the end of the day.
 
Did see said Army mention the new 6.8x51 using a 135 grain bullet which would hit a MV 3,000 fps from a 16" barrel with its extreme pressure hybrid three-piece case, stainless steel head, interconnecting aluminum locking washer to the brass body.

USSOCOM with their new Mid Range Gas Gun-Sniper, MRGG-S, (20" barrel-choose a Geissle), chambered for firing the new gen high ballistic coefficient longer bullets in a standard pressure low cost brass cased 6.5 Creedmoor round, with a 140 grain bullet, reported if fired from a 16 " barrel would give a MV of 2,500 fps.

Sierra ballistic charts show at 1,000 yards if fired at their different MVs the SMK 140 grain 6.5mm bullet slowed to 1,198 fps whereas 135 gn 6.8mm SMK at only 1,321 fps, so 6.8x51 gives a marginal 10% better terminal velocity at 1,000 yards with its required extreme pressure case plus a cost of a round of 500% + or more than that of a 6.5 Creedmoor cost. Looks to me very weak Army logic justification to spend the extra tens of $billions per year for the foreseeable future on the 6.8x51.
 
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Cordy said:
Sierra ballistic charts show at 1,000 yards if fired at their different MVs the SMK 140 grain 6.5mm bullet slowed to 1,198 fps whereas 135 gn 6.8mm SMK at only 1,321 fps, so 6.8x51 gives a marginal 10% better terminal velocity at 1,000 yards with its required extreme pressure case plus a cost of a round of 500% + or more than that of a 6.5 Creedmoor cost. Looks to me very weak Army logic justification to spend the extra tens of $billions per year for the foreseeable future on the 6.8x51.
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A 6.5mm round trying to defeat the plates XM1184 is trying to defeat wouldn't be 20% the cost, it would be similar to the current cost of M1158. Again, the cost driver for XM1184 isn't the case design, though there are many problems there, rather it is the extremely expensive and difficult to produce projectile.

Don't get me wrong, NGSW is dumb and bad, but it is dumb and bad for reasont you aren't reaply understanding.
 
Cordy said:
Sierra ballistic charts show at 1,000 yards if fired at their different MVs the SMK 140 grain 6.5mm bullet slowed to 1,198 fps whereas 135 gn 6.8mm SMK at only 1,321 fps, so 6.8x51 gives a marginal 10% better terminal velocity at 1,000 yards with its required extreme pressure case plus a cost of a round of 500% + or more than that of a 6.5 Creedmoor cost. Looks to me very weak Army logic justification to spend the extra tens of $billions per year for the foreseeable future on the 6.8x51.
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It's important to remember that it's KE (0.5mv^2) more than velocity alone that counts when it hits something.

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Scott Kenny said:
The case itself has 3 parts, Stainless steel case head, brass case body, and a lockwasher between the two. So there's a whole assembly step that has to happen to those stupid things before you can load the casing.

All of which adds costs.

But yes, the extreme pressure round is for busting the Russian dreadnought body armor. So it's probably tungsten core if not DU. And frankly tungsten is the more expensive option there, since DU is a waste product from reactor fuel.



The only reason SIG had ludicrous pressures is because their rifle design needed a 13" barrel to come under the length limit with the suppressor on.

The bullpup rifle worked just fine at regular pressures, because its barrel was some 18-22" long (I forget the exact spec, want to say 20"). And the spec for the cartridge was fundamentally 140gr at 3000fps, which is .270 Winchester loads. If you can use 1950s powders to get a 150gr bullet at 2800fps out of 7.62x51 instead of x63, you can do the same thing with a .277 bullet instead.

I really hope Truevelocity can get their ammo out into the world as a more standard thing. Especially practice ammo stuff, where you want it to be as cheap as possible.

There used to be some pure-polymer shotgun ammo out there in the early 2000s, not sure whatever happened to them. Probably low number of reloading times. But they sponsored a lot of various shotgun competitions back in the day, and each loading type was color-coded on the casing (1oz of #6 shot was red, 1oz of #8 was green, etc. Think I'm right on the colors.). You'd just shovel all the empties into the appropriate color box at the end of the day.
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I thought I read that they got rid of the lock washer type part somehow which simplifies the production process, but I'm not entirely sure. To not be entirely unfair to SIG it was the Army who had that requirement for overall length. A very questionable requirement of the program if you ask me. The Army wants a standard issue service rifle (or carbine technically) that can reach out, reliably hit and incapacitate an enemy at something absurd like 1,000 meters, but with suppressor fitted they don't want it longer than a standard issue M4 (no suppressor). I'm not a firearms designer but I think if you're looking for that sort of effective range you really ought to be willing to accept something a bit longer than an M4. Yet anyone who might have questioned some of these requirements probably was ignored.

All of the designs had to make compromises to meet that length requirement. The Army isn't very fond of the bullpup layout and I'm sure True Velocity knew that. I'm not sure what the barrel length was of the Textron entry that used the cased telescoped ammunition. I assume it was a bit longer than the 13" barrel of the SIG design but definitely not as long as the barrel of the True Velocity bullpup. So, I'd also assume that the 6.8mm CT ammo had higher pressures than average, but not as high as the hybrid case SIG stuff.

There are a whole lot of other choices I've really got to question the logic of too. The XM250 looks like it has a lot of promise but the Army decides they want to save a small amount of weight and cost by not including a quick-change barrel? That seems to be discarding a great many lessons learned dating back to WWII in favor of Afghanistan experience of exchanging fire at great distances. It seems like a whole lot is being ignored in chasing some illusion that every infantryman can be made a marksman taking out the enemy beyond the effective range of their own small arms. I've read a good deal about the rather disastrous management of the Ordinance Department from WWII up into the Vietnam War, but in many ways it seems like the process of specifying, designing, and fielding new small arms hasn't improved much since those days.
 
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Apparently at least one grunt isn't very impressed with the gun. And ammo. And the silencer. And the optic. And he was kind enough to include pics.

I was recently quoted in multiple publications saying nice things about the Sig XM7 / Vortex XM157, and unfortunately, the 10 minutes worth of critiques I had before saying one nice thing didn't quite make the cut. So here is my list of grievances:

I have never seen a weapon have so many malfunctions. Namely failure to extract/eject even when properly cleaned (checked by sig guy) and on adverse gas setting using the GP round

For the task and purpose dude that made the YouTube video, you had my name, you could've reached out to me for comment instead of just requoting me. I included a picture of a 3/8" steel target that has been shot by several hundred rounds of the "spicy" ammo, from 100-300m that you hypothesized could be used against light armor.

Optic: The Vortex XM157 is shit. I usually like vortex products, but this one is bad. Several ocular focus adjustment rings/diopter adjustments just randomly migrated, the brightest setting is nowhere near bright enough (almost invisible on a sunny day), I included a picture of one that decided it wanted to red screen of death after being shot on a flat range, but we had another that just stopped turning on all together. Severe zero migration on the lasers.

Suppressor: works fine, but the locking ring is so stupid. You're giving infantryman a suppressor that if you twist the suppressor at all after "locking" the ring, it flips the lugs/breaks?? We had two break in the classroom.

BFA: Stupid. Absolute nightmare for SI when you have to remove the suppressor and swap the bolt in the field

Ammo: two piece casing blows apart occasionally, stuck casings are common in the XM250

Rail: half of them came misaligned from Sig which is further indicative of bad QC.
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https://www.reddit.com/r/army/comments/1flgkbl/my_response_to_task_purpose
View: https://www.reddit.com/r/army/comments/1flgkbl/my_response_to_task_purpose/
 
The task and purpose guy used to have an awesome show but it changed pretty radically a year or more back. Much more relaxed and you could tell the guy was just being himself.
 
The malfunctions and QC issues are alarming, especially as the SIG's "reliability" was cited as key to its select (and the other two bidders were eliminated before down-select on grounds including perceived reliability issues).
 
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As understand with the 6.8 x 51 at the shoulder of the 7.62 x 51 they increased the dia by 1.5mm and made the shoulder 0.4mm fractionally longer from the base which would very marginally increase case capacity and they also increased shoulder angle from 20 to 30 degrees, depending on the manufacturing tolerances may be possibility of cross loading, though expect color of the 6.8 bi-metallic case would stop it.
 
Federal have introduced the 7mm Backcountry cartridge, six years in development, what is of interest is that its uses a one piece steel alloy case that can take 80,000 psi the same as the 6.8x51 and give similar performance, suggestions the steel alloy case (Peak Alloy) was developed to meet the very same high pressure specs called for in the US Army 6.8x51 - brass cases pressure limit approx. 65,000 psi.

The Sig Sauer 80,000 psi 6.8x51 round for the XM7 and XM250 is a 3 piece case, SS head, aluminum washer and brass body.

The Federal case is said to be comparable in price to standard brass cases plus 15% lighter whereas said the Sig Sauer is much more expensive as its more complicated to manufacture and reports that in the XM250 it has separated in the chamber on firing.
 
Impressed? I'd say Sig simply couldn't cook up ammos like TV and Textron so they brute forced it. End result is an absolute abomination. I couldn't imagine how one would react when the entire cartridge fragments into pieces and shotgun blast the entire receiver. At least with 556 the catridge could be bent not shatter into 3 different parts.
 
From Ian McCollum's description on Forgotten Weapons, I got the feeling this would be a quite unpleasant gun to fire with the 80,000 psi ammunition. This feeling may be worsened as the full-power ammunition won't be used for most training due to cost, so troops may be surprised.

One question I have is about the tri-metallic cartridge's susceptibility to galvanic corrosion. Get it damp, and the aluminum will start sacrificing itself to save the brass and steel parts. The testing should include storage in damp, salty conditions.
 
MihoshiK said:
I think the applicable acronym here is KISS.
Sig were so impressed with the technological terror they constructed they never bothered to ask if there was a simpler way to do things...
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No, SIG are just incompetent goobers. They are also winning contracts so they spend more on bribes/lobbying than actual RD&E, clearly.

RM277 was the real winner and probably wouldn't have any issues besides manual of arms if it had been selected.
 
Trying to put numbers on how much more costly is the Sig 6.8x51mm ammo. FWIW on the web the Sig Sauer reduced range hybrid cased 6.8x51mm training 113gr round in 460 cans for $1035.99, whereas 1,000 rounds of 7.62x51mm NATO Saltech FMJ 150 gr is available for $495, that would make the Sig 6.8x51 reduced range training round approx 4.7 times more costly than the 7.62x51mm, unknown is how much more costly is the actual operational Sig 6.8x51mm round is with its heavier bullet, presuming a 3 part bullet similar to the 855A1 design to penetrate hard targets and armor, sure the Army will get better prices for the Sig ammo but as they will in future be buying billion plus per year that equates to additional $billions spend from the Army budget for the foreseeable future. The above numbers need to be treated with a grain of salt, but think it gives a strong pointer of how much more expensive the Sig hybrid ammo will be compared to the conventional brass cased ammo as the 7.62 NATO rounds.
 
Kat Tsun said:
No, SIG are just incompetent goobers. They are also winning contracts so they spend more on bribes/lobbying than actual RD&E, clearly.

RM277 was the real winner and probably wouldn't have any issues besides manual of arms if it had been selected.
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All of the designs have their flaws IMHO due to rather questionable requirements. With the RM277 the Army was (and has long been) biased against bullpups from the start but the lack of a belt-fed LMG version hugely hurt their chances.
 
Colonial-Marine said:
All of the designs have their flaws IMHO due to rather questionable requirements. With the RM277 the Army was (and has long been) biased against bullpups from the start but the lack of a belt-fed LMG version hugely hurt their chances.
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Belt fed isn't really important and there's nothing that says they couldn't adopt the RM277 as a rifle and the XM250 in the RM277 caliber.

It happened with M16A2 and M249.
 
Kat Tsun said:
Belt fed isn't really important and there's nothing that says they couldn't adopt the RM277 as a rifle and the XM250 in the RM277 caliber.

It happened with M16A2 and M249.
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No, the whole contract was winner-take-all. Structured that way from the beginning.

So what needed to happen for any team to win was designing a good LMG and then figuring out how to make a rifle work. And the M250 is a good LMG. It's no Knights LAMG, but it's good enough. (for what it's worth, I don't think the Knights LAMG is good for bipod or tripod work)
 
Scott Kenny said:
No, the whole contract was winner-take-all. Structured that way from the beginning.

So what needed to happen for any team to win was designing a good LMG and then figuring out how to make a rifle work. And the M250 is a good LMG. It's no Knights LAMG, but it's good enough. (for what it's worth, I don't think the Knights LAMG is good for bipod or tripod work)
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There's no reason to design the contract like that if the U.S. military were still competently run though. Unfortunately, it's presently taking cues from India's business management schools in "dawdling 101". Unlike India, it seems to be aware of this, but NGSW doesn't seem to have benefited from this awareness.

The AR and rifle should have been separate competitions within the NGSW, like the IFCS rifle sight, and that would probably select RM277 and XM250 at the end of the day. Maybe. This is the same Army that bought the M17 MHS.
 
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yeetmahboi said:
Best option would be to couple TV polymer round with Sig's guns.
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Those don't have the required speed from the M7 rifle 13" barrel. (barrel had to be that short to meet the government overall length requirements with the suppressor on it)

There is a new Federal round that's come out, uses a steel case to handle the same pressure levels without needing the multiple parts. 7mm Backcountry.
 
Scott Kenny said:
Those don't have the required speed from the M7 rifle 13" barrel. (barrel had to be that short to meet the government overall length requirements with the suppressor on it)

There is a new Federal round that's come out, uses a steel case to handle the same pressure levels without needing the multiple parts. 7mm Backcountry.
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Forgot that the TV is shot out of a bullpup with an absurdly stubby suppressor for some reason.

In that case, it was either Sig or Textron, and the Army didn't want to hedge its bets on CT. Between 100 years of brass and steel cases, trialed by fire, and maybe 20 years for LSAT I'd say that's understandable.
 
yeetmahboi said:
Forgot that the TV is shot out of a bullpup with an absurdly stubby suppressor for some reason.

In that case, it was either Sig or Textron, and the Army didn't want to hedge its bets on CT. Between 100 years of brass and steel cases, trialed by fire, and maybe 20 years for LSAT I'd say that's understandable.
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I'm fairly sure the potato suppressor was selected so the TV design could stay within those length requirements. Even though the bullpup format allowed for a longer barrel it seems they still had to work pretty hard to meet that requirement, considering the TV polymer cases couldn't handle the same pressures as the other two.

I'd be interested in learning in what ways the Textron entry fell short in testing. Their CT ammo was the most ambitious but also required some rather unconventional internal operation IIRC.

Scott Kenny said:
There is a new Federal round that's come out, uses a steel case to handle the same pressure levels without needing the multiple parts. 7mm Backcountry.
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Switching to such a steel alloy case for the 6.8x51mm sounds like it would be an improvement. Although I assume the Army would have to specifically tell Sig to make such a change and they can't just steal the work of the Federal guys.

I thought I read somewhere that Sig had been able to delete the locking washer part in their hybrid case design so the ammo is just two pieces, but I could be mistaken.
 
Colonial-Marine said:
I thought I read somewhere that Sig had been able to delete the locking washer part in their hybrid case design so the ammo is just two pieces, but I could be mistaken
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They did the production ammo is such.

Apparently it made the issue of case head separation even worse so now you getting the issue of the base beling pulled off and the case proper getting stuck in the breech.

Resulting a Jam on the level of...

I need 15 minutes 2 pliars and likely a vice to unfuck this. May need to even grab the torch.
 
Firefinder said:
They did the production ammo is such.

Apparently it made the issue of case head separation even worse so now you getting the issue of the base beling pulled off and the case proper getting stuck in the breech.

Resulting a Jam on the level of...

I need 15 minutes 2 pliars and likely a vice to unfuck this. May need to even grab the torch.
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I'm sure there's a Stuck Case Tool for a .308 lurking around somewhere.

Still takes tools and some "percussive maintenance" though.
 
Colonial-Marine said:
I'm fairly sure the potato suppressor was selected so the TV design could stay within those length requirements. Even though the bullpup format allowed for a longer barrel it seems they still had to work pretty hard to meet that requirement, considering the TV polymer cases couldn't handle the same pressures as the other two…
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That’s not really accurate. TV’s case design can (IIRC) withstand up to 80,000 psi. They chose the bullpup layout to reduce barrel wear and muzzle blast while still meeting the Army’s ballistic requirements.

EDIT:
 
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Colonial-Marine said:
There are a whole lot of other choices I've really got to question the logic of too. The XM250 looks like it has a lot of promise but the Army decides they want to save a small amount of weight and cost by not including a quick-change barrel? That seems to be discarding a great many lessons learned dating back to WWII in favor of Afghanistan experience of exchanging fire at great distances. It seems like a whole lot is being ignored in chasing some illusion that every infantryman can be made a marksman taking out the enemy beyond the effective range of their own small arms. I've read a good deal about the rather disastrous management of the Ordinance Department from WWII up into the Vietnam War, but in many ways it seems like the process of specifying, designing, and fielding new small arms hasn't improved much since those days.
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IMO this can be applied to the entire NGSW program. Big Army is literally making the same mistake they made with the M14 (except this time it’s even worse due to us having 75+ years of data saying so).
 
Dragonlady said:
That’s not really accurate. TV’s case design can (IIRC) withstand up to 80,000 psi. They chose the bullpup layout to reduce barrel wear and muzzle blast while still meeting the Army’s ballistic requirements.

EDIT:
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Why did the TV case bother with the higher pressures when they don't need them?

SIG needed the ludicrous pressure due to the short barrel. TV had a long barrel so only operated at the typical ~55-65kpsi, well within the limits of brass cartridges. See also the TV range of commercial ammunition.



Dragonlady said:
IMO this can be applied to the entire NGSW program. Big Army is literally making the same mistake they made with the M14 (except this time it’s even worse due to us having 75+ years of data saying so).
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When I heard about it, I suggested someone take an old school BAR and/or M1 Garand chambered in .270 to the general in charge.
 
Scott Kenny said:
Why did the TV case bother with the higher pressures when they don't need them?

SIG needed the ludicrous pressure due to the short barrel. TV had a long barrel so only operated at the typical ~55-65kpsi, well within the limits of brass cartridges. See also the TV range of commercial ammunition.
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I meant that the case design could handle up to 80,000 psi if necessary. Had the Army wanted to combine the SIG gun with the TV ammo, they most likely would’ve been able to easily up the pressure to 80,000 in order to retain ballistics.
 

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