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NGSW Phase 2 Consolidation and info   Small Arms <20mm

Started 30/8/19 by gatnerd; 555266 views.
stancrist

From: stancrist

24/11/19

gatnerd said...

Something interesting I noticed in "NGSW Industry Day Slides" is their are two Gov's supplied projectiles - Surrogate and General Purpose.

General Purpose is the 6.8 EPR I linked earlier.

But the Surrogate appears to be a lead core VLD.

If the Surrogate is the stand in for the Tungsten AP round, and the Surrogate is 140gr, I'm curious if that means that the 6.8 GP is a different (presumably lighter) weight, say 120-125gr? 

It also raises a question about whether the 'ADVAP' is actually a tungsten tip EPR. S7 tool steel is 7.83g/cm3, whereas WC is 15.83g/cm3, so the two projectiles would end up radically different in weight.

Since the Surrogate round is 140gr, its reasonable to assume the AP round is ~140gr.

From all I've seen on the subject, I figured the Surrogate bullet is a substitute for the GP projectile, with "GP" being the current name for what originally was called ADVAP.

Is there reason to think GP and ADVAP are two different bullets?  Has anyone seen the "ADVAP" term being used by the Army or industry since the GP bullet was debuted?

gatnerd

From: gatnerd

24/11/19

"From all I've seen on the subject, I figured the Surrogate bullet is a substitute for the GP projectile, with "GP" being the current name for what originally was called ADVAP."

From the looks of it, contractors and Gov't testing involves testing both the GP and Surrogate, with plenty of GP's provided. So the Surrogate doesn't make sense as a Surrogate for GP, given that they were handing out large quantities of the GP.

https://imlive.s3.amazonaws.com/Federal%20Government/ID5041233544762060809463086928281536454/NGSW_Industry_Day_Slides.pdf

 

Some more info:

"Additionally, offerors must develop two different ammunition cartridges utilizing government specified 6.8mm projectiles.

* General Purpose (GP) per Drawing titled “6.8MM GENERAL PURPOSE (GP)”. The GP cartridge provides all-purpose solutions for combat, limited training, and basic qualification.
* Surrogate per Drawing 13072652. The surrogate cartridge is designed to mimic the behavior of combat projectiles from a weapon design standpoint. Surrogate projectiles may not be completely representative of the final combat ammunition configuration which are expected to vary during development. Surrogates are intended to be a close replacement shape of the final combat rounds."

http://soldiersystems.net/2018/10/04/161298/

 

71. Question: In reference to Attachment 3 - Ammunition Data’s General Purpose Projectile requirements, does the Government intend to maintain the same envelope for the General Purpose Projectile as the Surrogate? The General Purpose Projectile concept is pushing the maximum envelope of our current system, which was designed around the surrogate. If the maximum overall envelop General Purpose Projectile changes, it will greatly impact overall design parameters; significantly altering development.

Response: Yes, the Government intends to maintain the same envelope for the General Purpose Projectile as described in Attachment 3 – Ammunition Data. 

83. Question: Is it preferred for awardees’ ammunition to utilize the USG projectile during PTs rather than a surrogate projectile?

Response: The NGSW effort will utilize both the USG General Purpose and Surrogate Projectiles during Prototype Testing. Please see Attachment 9 Prototype Test Outline provides details on the quantity and projectile type used in each test. 

https://imlive.s3.amazonaws.com/Federal%20Government/ID5041233544762060809463086928281536454/NGSW_Industry_Questions_&_Comments_62_-_89.pdf

160. Question: In Attachment 3, can USG modify the GP projectile design to share a common ogive length with the Surrogate and SP Envelope projectiles?

Response: No, the Government does not intend to modify the surrogate projectile since it is designed to mimic the behavior of existing and future combat projectiles.

161. Question: In Attachment 3, is USG interested in other 6.8mm projectile technology that becomes available during the estimated 27 month PON effort?

Response: No, the Government intends to provide the 6.8mm projectile. In the future, the Government may explore other projectile technology.

173. Question: What purpose does the surrogate provide?

Response: The surrogate projectile is designed to mimic the behavior of existing and future combat projectiles.

https://imlive.s3.amazonaws.com/Federal%20Government/ID5041233544762060809463086928281536454/NGSW_Industry_Questions_&_Comments_152_-_281_Part_2.pdf

 

-->Based on these various Q&A's, it seems the Surrogate is distinct from the GP. And the Surrogate is for a 'combat projectile.' Given the already extremely potent 'General Purpose' projectile design, we can reasonably infer that this 'Combat Projectile' is the special AP design. 

 

"Is there reason to think GP and ADVAP are two different bullets?  Has anyone seen the "ADVAP" term being used by the Army or industry since the GP bullet was debuted?"

Per Kitup, source of our 6.8 GP photo:

Two Army officials with knowledge of the new 6.8mm General Purpose Projectile confirms to Military.com that it is very similar to the composition of the M855A1 and M80A1, consisting of an exposed steel penetrator that sits on top of a copper slug and is partially encased in a copper jacket.

https://www.military.com/daily-news/2019/10/27/inside-armys-quest-revolutionary-new-bullet.html

 

Now per Buffman, we've seen Level IV stop M80A1 steel tip at 3400fps from 40' away. Given the AP requirement of NGSW, it strains credulity (even for the Army) that they would be trying to achieve their AP goals with a steel tip projectile.

Meanwhile, previous mention of ADVAP mentions Tungsten:

https://www.thefirearmblog.com/blog/2018/01/29/us-armys-xm1158-advap-round-revealed-tungsten-cored-epr-based-design-cheaper-quicker-produce/

 

Lastly, given the high cost of Tungsten, its hard to imagine the tungsten tip rounds would be used casually for 'general purpose' training use, or use even in combat against unarmored adversaries.  

  • Edited 25 November 2019 2:50  by  gatnerd
gatnerd

From: gatnerd

25/11/19

I found this image buried in TFB comments, which in turn lead to a google reverse image search for the original, largest photo:

https://twitter.com/secarmy/status/1055863713058734080

https://i.ibb.co/sKr7Y8R/original-1.jpg

Zooming in:

"Develop suite of ammunition to be fielded with the Next Generation Squad Weapon Program. Ammunition for the first unit equipped 2022 will be will be the General Purpose (GP) round and the Special Purpose (SP) Round."

"Adopt Battle Proven Enhanced Performance Round (EPR) designs for GP Round."

"Implement lessons learned from the XM1158 design for SP Round."

 

  • Edited 25 November 2019 4:13  by  gatnerd
EmericD

From: EmericD

25/11/19

gatnerd said...

Something interesting I noticed in "NGSW Industry Day Slides" is their are two Gov's supplied projectiles - Surrogate and General Purpose.

I always thought that the "surrogate" bullet was the 135 gr SMK bullet that was used during the development of the .277 USA round, but the shape of this SMK bullet does not fit the picture (the ogive looks really secant).

It better looks like a reduced Berger .284" / 168 gr VLD...

gatnerd

From: gatnerd

25/11/19

"I always thought that the "surrogate" bullet was the 135 gr SMK bullet that was used during the development of the .277 USA round, but the shape of this SMK bullet does not fit the picture (the ogive looks really secant).

It better looks like a reduced Berger .284" / 168 gr VLD..."

 Perhaps one of the Berger .270's?

https://bergerbullets.com/product-category/bullets/?caliber=270-caliber

Maybe the 140gr classic hunter?

https://bergerbullets.com/product/270-caliber-140-grain-classic-hunter/

 

Presumably, the 6.8 prototypes we've seen are loaded with the same Surrogate projectile?

6.8 sherwood:

http://soldiersystems.net/blog1/wp-content/uploads/2019/06/image-863.jpg

6.8 sig

https://www.thefirearmblog.com/blog/wp-content/uploads/2019/09/dfdf.png

6.8 TV:

https://www.thefirearmblog.com/blog/wp-content/uploads/2019/09/True-Velocity-6.8mm-Composite-Cased-General-Dynsmics-NGSW-2.jpg

I don't have a trained eye like you for bullets; are they all using the same projectile in their demo cartridges? And does it look like the Berger?

 

From one of the Q&A's, it sounded like the Ogive of the 6.8 GP was longer than that of the 6.8 Surrogate:

71. Question: In reference to Attachment 3 - Ammunition Data’s General Purpose Projectile requirements, does the Government intend to maintain the same envelope for the General Purpose Projectile as the Surrogate? The General Purpose Projectile concept is pushing the maximum envelope of our current system, which was designed around the surrogate. If the maximum overall envelop General Purpose Projectile changes, it will greatly impact overall design parameters; significantly altering development.

 

160. Question: In Attachment 3, can USG modify the GP projectile design to share a common ogive length with the Surrogate and SP Envelope projectiles?

Response: No, the Government does not intend to modify the surrogate projectile since it is designed to mimic the behavior of existing and future combat projectiles.

stancrist

From: stancrist

25/11/19

gatnerd said...

"I always thought that the "surrogate" bullet was the 135 gr SMK bullet that was used during the development of the .277 USA round, but the shape of this SMK bullet does not fit the picture (the ogive looks really secant).

It better looks like a reduced Berger .284" / 168 gr VLD..."

 Perhaps one of the Berger .270's?

Maybe the 140gr classic hunter?

The pic you posted earlier looks like an exact copy of the 130gr Classic Hunter (Part # 27570) shown in the Berger chart below.

Image result for berger .277 vld

stancrist

From: stancrist

25/11/19

gatnerd said...

I found this image buried in TFB comments, which in turn lead to a google reverse image search for the original, largest photo:

https://i.ibb.co/sKr7Y8R/original-1.jpg

Zooming in:

"Develop suite of ammunition to be fielded with the Next Generation Squad Weapon Program. Ammunition for the first unit equipped 2022 will be will be the General Purpose (GP) round and the Special Purpose (SP) Round."

"Adopt Battle Proven Enhanced Performance Round (EPR) designs for GP Round."

"Implement lessons learned from the XM1158 design for SP Round.

Great find!  I wonder if the "GP" and "SP" nomenclature are just for use during development, or will they replace the traditional "Ball" and "AP" terms if the NGSW enters service?

EmericD

From: EmericD

25/11/19

gatnerd said...

Perhaps one of the Berger .270's?

https://bergerbullets.com/product-category/bullets/?caliber=270-caliber

Maybe the 140gr classic hunter?

https://bergerbullets.com/product/270-caliber-140-grain-classic-hunter/

Maybe, but both the 130 grs & 140 grs from Berger are too short (1.24" and 1.274" respectively) compared with the estimated ~1.40" of the EPR bullet. On the other hand, that could explain the comments of some competitors...

gatnerd

From: gatnerd

25/11/19

"The pic you posted earlier looks like an exact copy of the 130gr Classic Hunter (Part # 27570) shown in the Berger chart below."

That does look very similar. 

There's also the question of - how much weight do we give an image in the power point presentation? Is it the surrogate, or just a handy image they grabbed?

A more reliable but more difficult to gauge metric would be examining the shown projectiles used in the 6.8 prototypes.

Right now, my 140gr hunch is based on the 6.8 Cobalt/Mars - it seems odd that they'd be advertising a 140gr @ 3200fps if the Surrogate was a 130gr.

 

"Great find!"  

Thanks! Yeah, I was really tickled when i stumbled across that image in the TFB comments. It was really a stroke of luck / late night internet madness.

 

"I wonder if the "GP" and "SP" nomenclature are just for use during development, or will they replace the traditional "Ball" and "AP" terms if the NGSW enters service?"

Hard to say. I hope they do though.

"Ball" doesn't really do the EPR justice. Its a 2/3 AP projectile that also fragments - which really is a wonderful, 'General Purpose' projectile design. 

And since the EPR - especially this really nasty long 6.8 EPR - has ~comparable penetration to historical AP rounds, I also like 'Special Purpose' as a descriptor for the specialist, extra AP Tungsten projectile. 

 

gatnerd

From: gatnerd

25/11/19

"Maybe, but both the 130 grs & 140 grs from Berger are too short (1.24" and 1.274" respectively) compared with the estimated ~1.40" of the EPR bullet. On the other hand, that could explain the comments of some competitors..."

Yes, the comments definitely suggest the EPR 'GP' is longer then the Surrogate. And of course, if the Surrogate = 6.8 EPR, then there would be no point in the Surrogate for developing the cartridge. 

And if we're talking about a Tungsten 'SP' round, I imagine it would have to be shorter then the 6.8 GP, due to WC being 2x as dense as steel, if the projectile is to remain a comparable weight. 

For example, the Penetrator weight of the M80A1 is 44gr. Same exact size in WC would be 88gr - so a Tungsten M80A1 EPR would weigh 174gr. The result would be a dramatically different velocity from the 130gr original.  

Perhaps maybe a Tungsten core base with polymer tip to lengthen the ogive an mimic the shape of the 6.8 GP? Or replacing the copper base with aluminum? 

 

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