gatnerd

Military Guns and Ammunition

Hosted by gatnerd

This is intended for people interested in the subject of military guns and their ammunition, with emphasis on automatic weapons.

  • 3337
    MEMBERS
  • 189769
    MESSAGES
  • 3
    POSTS TODAY

Discussions

NGSW Phase 2 Consolidation and info   Small Arms <20mm

Started 30/8/19 by gatnerd; 501870 views.
stancrist

From: stancrist

21-May

DavidPawley said:

...just mine the PLAN port & crater the runways of the PLAAF airbase.

ROFL.  smile

EmericD

From: EmericD

21-May

Guardsman26 said:

As I mentioned above, there is the SP round with is the armoured piercing loading that cracks Level 4 plates at 500+ metres.

Current 7.62x51 mm could do that up to 200+ m with medium length WC core, and to higher distance with the very long "Stiletto" core or the XM948 SLAP. Those latest rounds are already existing and no EU countries bought them in large volume, so I don't think that the existence of the SP round will be a pivoting point to the adoption of the 6.8x51 mm vs. 7.62x51 mm.

Guardsman26 said:

Second, there is a new standard loading, the GP round, which may even be fired at standard pressures and have MV of 875 mps / 2,900 fps. This would allow lightweight polymer cartridges to be used, reducing weight - but it would still be superior to 7.62x51 mm NATO in performance at all ranges due to its greater efficiency.

I don't think that a polymer-cased 6.8x51 mm will be so attractive versus a polymer-cased version of the M80A1, which is already delivering nearly anything you can expect from a "low pressure brass case" 6.8 mm. The 6.8 mm will have the edge after 400 m, and definitively better after 600 m, but armies will probably estimate that it's a limited gain at a large cost.

US SOCOM, after seeing from the insight all the greatness of the 6.8x51 mm, decided to resume its 6.5 mm Creedmoor program.

schnuersi

From: schnuersi

21-May

EmericD said:

US SOCOM, after seeing from the insight all the greatness of the 6.8x51 mm, decided to resume its 6.5 mm Creedmoor program.

That is what allways puzzeled me. The 6,5 Creedmore allready does what the 6,8x51 is supposed to do. Its a established and mature design. Even if the Creedmore is not an option the 6,5x55 Swedish does the same as well. The 6,8x51 tp me allways seems a case of reinventing the wheel.

Apsyda

From: Apsyda

21-May

A lot of that is purely speculative in terms of how it will be rolled out and the effectiveness of doing so, especially with regards to the plate cracking ability of the SP round. Perhaps with tungsten it could at a shorter range, but if we're back to using tungsten penetrators this entire program itself was a bust.

Nbunny12

From: Nbunny12

21-May

Interesting to read, useful information really.

schnuersi

From: schnuersi

21-May

Apsyda said:

but if we're back to using tungsten penetrators this entire program itself was a bust.

Its simply an urealistic goal to penetrate modern high performance body armor with a steel penetrator at usefull combat ranges with a ME in the range of what is currently concidered full power rifle.

Apsyda

From: Apsyda

21-May

https://www.gao.gov/docket/b-420766.1
Lone Star/True Velocity finally submitted their bid protest.
Probably won't go anywhere, but it was to be expected eventually regardless. Without this NGSW contract Lone Star as an acquisition is mostly useless and is going to hurt True Velocity as a company pretty significantly. Maybe GAO finds something, probably won't.

stancrist

From: stancrist

21-May

schnuersi said:

That is what allways puzzeled me. The 6,5 Creedmore allready does what the 6,8x51 is supposed to do. Its a established and mature design. Even if the Creedmore is not an option the 6,5x55 Swedish does the same as well. The 6,8x51 tp me allways seems a case of reinventing the wheel.

Perhaps.  I think it would depend upon how much difference there is in performance.

And if one wants to go for an existing cartridge, 6.5x55 seems to me like a bad choice.

As shown in the pic below, 6.5x55 is too long to be used in rifles designed for 7.62x51.

Mr. T (MrT4)

From: Mr. T (MrT4)

21-May

6.5x55 is outdated  newer 6.5 cartriges more than emulate its performance in oal suitable for existing 308 magazines. 6.8x51 stuffed magnum performance in a case that fits the .308 mags. But high pressure is hardly free lunch.

'' This basicaly what we get when we are limited to magazine oal and case rim dimensions.

This is the slightly old table from Litz , its basicaly .308win ,7-08 ,260Rem  ,234Win  , all just necked down .308win  .

I am somewhat surprised SOCOM picked 6.5creedmoor over old .260Rem , as 6.5creedmoor is a relatively poor design with internal ballistics issues (its extremely hard to load to low ES and SDs) and worse feeding candidate than .260Rem that would be perfect for use in full auto guns.

A number of recent calibers out of the US are quite poorly designed jet still gained some popularity. 6.5 Creedmoor, 6ARC, 22Nosler  each one with a bunch of issues .

Constraining your ammo to magazine length can really compromise performance. Oftentimes you have to use a stubby, low BC bullet just so it fits.

You can see substantial performance gains at the same magazine length if your neck down to a smaller caliber (re-barrel). This allows your bullet to have a proportionally longer nose (higher BC) and a higher powder-to-bullet weight ratio which makes more velocity.

Consider this example between a 308 Win vs 243 Win.

The 308 will push a 175-grain bullet around 2650 fps. The 243 will push a 105-grain hybrid at 3000 fps, plus the 105 has a higher BC!

gatnerd

From: gatnerd

21-May

“US SOCOM, after seeing from the insight all the greatness of the 6.8x51 mm, decided to resume its 6.5 mm Creedmoor program“

This one is quite surprising. As a replacement for 5.56, 6.8 seems pretty nuts.

But as a replacement for 7.62 or 6.5C,it seems much more compelling. There weapon and ammo weight is essentially identical but with much better ballistic performance for 6.8.

Ii wonder what SF saw that made them want to go back to 6.5?

TOP