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Chinese Level IV vs Tungsten .338   Small Arms <20mm

Started 29-Sep by gatnerd; 1877 views.
In reply toRe: msg 7
gatnerd

From: gatnerd

1-Oct

So I found the G7 for the 248gr AP load:

https://www.fiocchi.com/en/product/338-lapua-mag-fmjap-2

And here's the impact results, using Buffman's velocity:

So at 200yd, it was still impacting with both good velocity and tremendous energy.

Yet was stopped by a $119 chinese plate. 

Whats interesting is Lapua advertises this round as 906 m/s (2970fps) from a 26" barrel. Assuming thats the real velocity, and Buffman got a slower handload to test, we would see a further AP.

Re-running the #'s based on this 2970fps velocity, we would hit the 'Penetrate' velocity of 2560fps out to 250yds. 

But we'd still hit the 'not penetrate' velocity of 2421fps @ 310yd. 

While this would certainly be better, it still bodes very poorly for the 6.8 NGSW, and would also relegate the .338 LWMMG to AP at 5.56 SAW distances.

  • Edited 01 October 2020 3:12  by  gatnerd
In reply toRe: msg 8
gatnerd

From: gatnerd

1-Oct

One potential variable for future AP - and perhaps the last hope for 6.8 NGSW - is Tungsten Hardness. 

Nammo lists their HV at 1200-1500:

However Lehigh lists their 300gr Tungsten at 1800HV:

So perhaps increases in tungsten hardness will offer improvement in AP ability?

QuintusO

From: QuintusO

1-Oct

I've been warning about this for five years, not that anyone listens to me. 

Wessels3

From: Wessels3

4-Oct

I wonder what the impact effect will be on the individual wearing the plate?, even if the plate is not pierced?

Wessels3

From: Wessels3

4-Oct

nless there's some unknown, serious improvement in Tungsten AP tech, its looking like NGSW will be obsolete for AP by the time its introduced.  At which point we'd be stuck with a bunch of magnum battle rifles that can't penetrate armor. 

For "ordinary" infantry combat, it means going for hits outside of the plates, i.e. highly controllable, rapid semi-auto or burst fire. Back to 5.56x45.

gatnerd

From: gatnerd

4-Oct

Wessels3 said:

I wonder what the impact effect will be on the individual wearing the plate?, even if the plate is not pierced?

Buffman said it was around 25-30mm backface deformation @ 200yd, which is well within safe limits. It would hurt like hell, certainly, and theres possibility of cracking a rib, but not lethal by any means. 

Here's a soldier in Iraq getting tagged in the armor from fairly close range with what I assume to be 7.62x54. Dude pops right back up and is calling for fire support in a matter of seconds:

https://youtu.be/tMMSA3opBk4?t=52

And of course, any widescale deployment of .338 and or Tunsgten (either 6.8 or .338) would prompt armor manufacturers to design for that in mind. 

Which would both reduce armor penetration risk, as well as likely mitigate backface deformation. 

EmericD

From: EmericD

4-Oct

Buffman said it was around 25-30mm backface deformation @ 200yd, which is well within safe limits. 

If the plate shows a permanent deformation of 25-30 mm, then the backface deformation in plastilina is guaranteed to be much more than that, and absolutely not "within safe limits" !

roguetechie

From: roguetechie

4-Oct

Yeah a permanent 25-30 indicates an instantaneous well over the all important 44mm mark.

gatnerd

From: gatnerd

4-Oct

EmericD said:

If the plate shows a permanent deformation of 25-30 mm, then the backface deformation in plastilina is guaranteed to be much more than that, and absolutely not "within safe limits" !

It was 25-30mm in the clay backing he uses for his tests, which he tries to do as close to NIJ as possible for an private individual.

Its definitely more of a dent then what we'd see with lesser calibers, but well bellow the 44mm clay depth approved by NIJ:

Re-running the #s with the ballistic calculator (248gr 0.285 G7 @ 2730fps) the .338 is hitting the NIJ Level IV .30-06 energy level of 2800ft/lbs at 310yds, which Level IV is designed to stop safely at 40'.

So we'd see:

-100yds = Armor penetrated 

-200yds = Armor not penetrated, big backface deformation 

-300-1500yds = Armor not penetrated, backface deformation within specs 

And of course, the plate tested is the absolute cheapest, Chinese plate designed for commercial civilian sale. 

  • Edited 04 October 2020 18:05  by  gatnerd
gatnerd

From: gatnerd

4-Oct

Emeric, since you're privy to a lot more Tungsten testing then we are, would you expect the 300gr Tungsten .338 to have substantially more AP capability due to the heavier/longer penetrator? 

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