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New 5.8mm DBP191 ball and DVC12 AP round info and comparisons with 6 ARC and .22   Ammunition <20mm

Started 28-Oct by Augmentcore; 950 views.
Augmentcore

From: Augmentcore

28-Oct

Recently PLA has released new 5.8mm cartridges together with new 5.8mm assault rifle and new belt-fed SAW machine gun.  The main characteristics of the two main-combat cartridges (steel-core ball and tungsten-core AP) of PLA in the future are listed below :

5.8mm DVC12 AP details:

Muzzle velocity: 890m/s (from 22' barrel)

Bullet weight: 5.6g (87gr)

Penetrating ability: 10mm RHA steel@30 ° @200m range, better than 7.62x54R B-32 API, and 100m stronger than 5.56 M995 AP.

Muzzle energy: 2,220J 

Ballistic coefficint: 0.230 G7 BC

5.8mm DBP191 ball details:

Bullet weight: 4.8g (74gr) (NOT 4.6g OF THE OLD DBP10 AND THE FAILED LIGHT BULLET TESTING GROUP CALLED 18-1 IN 2018!)

Propellants: NEW DBEF-3/1 double-base (the same as the Chinese-export 7.62 NATO, generally believed that the improvement of the propellant is mainly because the introduce of Finnish sniper propellant (together with .338 Lapua), NOT the older propellant which can be dated back to the propellant prepared for 7.62x39mm Type 56 introduced in Soviet era). And the pressure has greatly incrased from 280MPa to about 330-350MPa, which may cause severe blast in the old QBZ95/QBZ03 series.

Muzzle velocity: 880m/s(from 14.5' barrrel on QBZ191), 920m/s(from unknown length barrel on QJS203 new belt-fed SAW based on 5.56 Negev and aims at M249 SAW)

Ballistic coefficient: 0.198 G7 BC (Newly designed hybrid-ogive bullet, different from DBU141 pure lead core sniper ball.)

Now the question is: Is DVC12 capable of becoming a "GPC" cartridge if they keep the power and the bullet weight and ogive and just change the tungsten AP core into the lead-steel structure like M855 to reduce price? ( 0.230 G7 BC , 890m/s muzzle velocity, 2,220J muzzle energy).  And most importantly, is 6mm ARC and .224 Valkyrie suitable to have better performance in GPC-purpose than 5.8x42 Chinese new main-combat cartridges in the future? If not, Which cartridge can undertake this task? 

gatnerd

From: gatnerd

28-Oct

Great info, thank you for sharing. Its generally harder to get Chinese specs on their small arms then US/EU/Russia, so this is very helpful.

In terms of being a GPC, theres a sliding scale of what people consider plausible as a true GPC round.

Certainly though of 5.56 vs 5.45 vs 5.8, the 5.8 is the closest to satisfying the GPC requirement. 

roguetechie

From: roguetechie

28-Oct

Do you have good pictures of the belt fed?

I have some pictures of multiple different prototypes (including one that has a 7.62 NATO big brother) but I'm curious to see any pictures you may have.

stancrist

From: stancrist

29-Oct

Augmentcore said:

And most importantly, is 6mm ARC and .224 Valkyrie suitable to have better performance in GPC-purpose than 5.8x42 Chinese new main-combat cartridges in the future? If not, Which cartridge can undertake this task?

As gatnerd noted, it depends upon what "GPC" means, and that varies.  If a GPC is seen as a common caliber for squad weapons, then in my opinion only the 5.8x42 is suitable.

That's  because I think .22 caliber is too small for adequate tracer visibility at long range, which rules out .224 Valkyrie, and 6mm ARC has too many unresolved issues* to make it a viable military round.

*6mm AR issues:

   - magazine capacity (25 rounds)

   - magazine reliability (inconsistent)

   - lack of disintegrating links

   - it is unknown if belt-fed machine guns in 6mm ARC will work reliably

What do I think might be able to undertake the task?  I'd say combine 6mm ARC with .224 Valkyrie to make 6mm Valkyrie.

That should enable use of 30-round polymer magazines made for 6.8 SPC, and M68 metallic links developed for 6.8 SPC.

                                                                 6.8 SPC                                                 .224 Valkyrie

roguetechie

From: roguetechie

29-Oct

That sounds quite interesting Stan.

Now if only we can get them to adopt an optimized high pressure bolt and extension design we've got something really worth doing!

Without the high pressure optimized bolt group you run into the issue that's already handicapping both these rounds, pressure and bolt thrust limitations.

nincomp

From: nincomp

29-Oct

As others have noted, there has been great debate over the exact definition of GPC.  It was discussed a great deal on this site a decade or so ago.  From what I recall, some wanted the projectile to be effective out to 1000m.  Over time, more argued for shorter differences, down to as little as 600m.  Early on, a number of us here figured that the 6.5 Grendel was not quite powerful enough, if that gives you any idea.  

The adoption of lead-free bullets had a major impact on meeting earlier GPC retained energy goals.  The less dense materials being considered for a general-use bullet dropped the BC to where meeting even 800m goals began to require so much propellant that the cartridge edged closer and closer to the size and weight of 7.62x51.   In fact, it can be argued that even the 7.62x51 with the current M80A1 projectile no longer meets the energy-at-range range goals of some GPC's proposed fifteen years ago.

Both the 6mm ARC and the .224 Valkyrie are hampered by the fact that they were designed to fit into the AR15 platform (without strengthening the bolt and barrel extension or widening the magazine).  This meant that the chamber pressures were reduced when compared to the 5.56x45.  Feeding the larger diameter cartridges through a magazine well designed for 5.56x45 is not optimum.  Note that when LWRCI developed the six8 carbine for the 6.8 SPC, they used a wider magazine.  Any new military cartridge should have its own platform to allow optimization.

  • Edited 29 October 2021 19:05  by  nincomp
Augmentcore

From: Augmentcore

29-Oct

Although the high L/D ratio bullet and high initial velocity can effectively improve the long-distance ballistic performance and make .243 or .260 level cartridges to reach .300 Magnum level like 6 Creedmoor made by Hornady or 6XC made by David Tubb, the barrel burning caused by it is a more serious problem, and this is totally different from long range single-shot or benchrest shooting wildcat bullets that folk shooting masters need to consider in America when they are trying to discuss 6.8 NGSW series whose design concept is based on 6.5 Creedmoor as an option of GPC cartridges( Don't forget the origin of 6.5 Creedmoor is to match the huge requirement of bolt-action precision shooting medium caliber rifle) and hardly of the previous discussions had considered this aspect. It may cause a serious decrease in the life of the barrel and accelerate the loss of the barrel and the frequency of maintenance. Although this is not annoying in a civilian competition where you can shoot leisurely, it is likely to be fatal on a battlefield where every second counts.

So in order to avoid the barrel burning in automatic mode, a meaningful diameter is .25 cal (only in my opinion). .260 cal is too big to get ideal ballistic coefficient like 6.5 Grendel (TOO slow), while .243 cal is too small to make multi-purpose bullets such as dim-tracer. What do you think?

EmericD

From: EmericD

30-Oct

Augmentcore said:

So in order to avoid the barrel burning in automatic mode, a meaningful diameter is .25 cal (only in my opinion). .260 cal is too big to get ideal ballistic coefficient like 6.5 Grendel (TOO slow), while .243 cal is too small to make multi-purpose bullets such as dim-tracer. What do you think?

"Optimum" bullet diameter is just a by-product of the amount of the muzzle energy you want to achieve from barrel length with an expansion ratio around 8-9.

The original idea was to duplicate the retained energy of the 7.62 x 51 mm with a smaller / lighter round, it was already demonstrated that you could achieve this goal at 600 m with a .264" bullet and ~2500 J of muzzle energy, but a .236" bullet and slightly less muzzle energy will be OK, or any diameter between (.243" and .257").

The .243" seems to be sufficient for long-range tracers and can be used in "micro action", while the .264" will eat too much internal space and will probably need a longer action.

smg762

From: smg762

30-Oct

Going back to the 5.8mm ammo, task and purpous has a new video on the chinese bullpup ...just uploaded right now

Augmentcore

From: Augmentcore

30-Oct

But the problem is that bullpup rifles like QBZ95 are now a marginalized part of China. The current new rifle like QBZ191 is just an imitation of the AR series and HK416, even the buttstock can only be retractable but not foldable (because the built-in reintroduction pipe has been almost reached the bottom plate of the buttstock like those old M16/M16A1), I think this can already explain the problem. So the problem of insufficient barrel length (14.5 in, the same as M4A1) will not only be faced by the American AR rifle, but the new Chinese rifle will also be troubled by this problem.

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