Tank Guns and Ammunition

[militarysta]

http://www.witu.mil.pl/www/biuletyn/zeszyty/20130126p.pdf

pages: 41-48

EXPERIMENTAL STUDIES OF SHAPED CHARGE DEFORMATION IMPACT ON REDUCTION SHAPED CHARGE JET EFECTIVENESS

Abstract:
The basic aim of the paper is to presents the results of experimental studies of the shaped charge deformation impact on the reduction of the shaped charge jet. Imperfections of a cumulative liner, explosives and a cover were introduced intentionally.
The imperfection resulted in the loss of symmetry in the axis of the charge. These imperfections have an adverse effect on the formation of the shaped charge jet, which was confirmed by experimental studies described below. Deformations introduced into the shape charge corresponded to the situations that take place during an interaction between PG 7 missile and a slat armour.
It was previously confirmed by suitable field tests within the frameworks of the project of passive defence of vehicles against a missile with a shape charge warhead. The following tests may therefore be regarded as a continuation of these works in the context
of the influence of the interaction between PG 7 missile and the slat armour on the phenomenon of the shaped charge jet. They also confirm the effectiveness of the bar armour, showing how a small deformation of the shape charge effectively interferes with the jet formation. This work allows us to conclude that the effective disorder of the shape charge jet formation is sufficient distortion of the
charge without damage (rupture of the outer skin, liner or explosive)

Keywords:
shaped charge, shaped charge jet, imperfection

screen shot software

 

[militarysta]

http://ilot.edu.pl/kones/2010/3_2010/2010_niezgoda_panowicz_sybilski_barnat_numerical_analysis.pdf

NUMERICAL ANALYSIS OF A SHELL WITH A MAIN SHAPED CHARGE WARHEAD STROKE INTO A BAR ARMOUR WITH SQUARE SECTION

Keywords:
bar armour, net armour, RPG vehicle protection, active protection systems, military vehicle

 

[militarysta]

http://ilot.edu.pl/kones/2011/1_2011/2011_szudrowicz_analysis_of_bar_and_net_screens_structure.pdf

ANALYSIS OF BAR AND NET SCREENS STRUCTURE PROTECTING VEHICLES AGAINST ANTI-TANK GRENADES FIRED FROM RPG-7
Keywords: bar armour, net armour, RPG vehicle protection, active protection systems, military vehicle

 

[militarysta]

http://www.witu.mil.pl/www/biuletyn/zeszyty/20110118p/51.pdf

EXPERIMENTAL TESTS OF THE CHOSEN TYPE OF THE ROD ARMOUR

 

[militarysta]

About 2001 USA reserches in thema adiabetic sheaping in WHA rods and DU

 

[Dejawolf]

Finnal verion M829 mesurement
rod only have circa 24x486mm, grey tip before rod (under balistic cap) have circa 6-24 x 51mm

"gray tip before rod" is actually part of the rod. so the whole rod is actually 506mm with frustum length 50, and tip diameter 10.
rod is 27mm diameter.

 

[militarysta]

More or less improved (whit tip) give us:

 

[militarysta]

 

[militarysta]

 

[militarysta]

Improved measurment M829A3 version, and M829A1 version:

Now, we can take together all M829xx penetrator only dimension and compare it (penetrator lenght x diameter x muzzle):

M829 - 540mm x ~18-26mm; 1650m/s
M829A1 - 695mm x 18-24mm; 1575m/s
M829A2 - 690mm x 18-22mm; 1680 m/s
M829A3 - 790mm x 22-26mm; 1555m/s

It's hightly unlike to achive penetration bigger then penetrator lenght, so penetration just must be smaller then rod lenght
They are many estimatous how many mm RHA shoud penetrate APFSDS. IMHO it's slighty above 90% penetrator lenght, and circa 0.95 for composite sabot. So penetration shoud be circa:
M829 - 530mm;
M829A1 - 625mm;
M829A2 - 655mm (composite sabot)
M829A3 - ~750mm (composite sabot)

for compare DM53 L-55:
DM53 - 660mm x 18-22mm, 1750m/s and "stupid RHA" equvalent circa between M829A1 and A2. Circa 635mm RHA on 2000m.

 

[methos]

Older (but afaik still accurate) data from Jane's abouM829A1:

Weight of penetrator: 4.6 kg
Length of complete round: 984 mm
Length of projectile assembly: 780 mm
Length of penetrator: 684 mm

Now, we can take together all M829xx penetrator only dimension and compare it (penetrator lenght x diameter x muzzle):

M829 - 540mm x ~18-26mm; 1650m/s
M829A1 - 695mm x 18-24mm; 1575m/s
M829A2 - 690mm x 18-22mm; 1680 m/s
M829A3 - 790mm x 22-26mm; 1555m/s

It's hightly unlike to achive penetration bigger then penetrator lenght, so penetration just must be smaller then rod lenght
They are many estimatous how many mm RHA shoud penetrate APFSDS. IMHO it's slighty above 90% penetrator lenght, and circa 0.95 for composite sabot. So penetration shoud be circa:
M829 - 530mm;
M829A1 - 625mm;
M829A2 - 655mm (composite sabot)
M829A3 - ~750mm (composite sabot)

for compare DM53 L-55:
DM53 - 660mm x 18-22mm, 1750m/s and "stupid RHA" equvalent circa between M829A1 and A2. Circa 635mm RHA on 2000m.

Sorry, but this is a completely superficial and also faulty approach. The length alone doesn't matter, the exact dimensions and the velocity matter:

- Source

Impact angle and shearing effects are also not taken into account. How did you come up with a 660 mm long penetrator for the DM53? Is this based on some real measurement or an estimate? I am asking because the weight values for the DM53 penetrator/projectile don't match up with your suggested dimensions.

 

[militarysta]

Older (but afaik still accurate) data from Jane's abouM829A1:

Weight of penetrator: 4.6 kg
Length of complete round: 984 mm
Length of projectile assembly: 780 mm
Length of penetrator: 684 mm

Im not sure if those 684mm is correct - looks that M829A1 and M892A2 have the same lenght of the penetrator.

Sorry, but this is a completely superficial and also faulty approach. The length alone doesn't matter, the exact dimensions and the velocity matter:

Of course that it can be wrong - why not, in that thema im not really sure.

How did you come up with a 660 mm long penetrator for the DM53? Is this based on some real measurement or an estimate? I am asking because the weight values for the DM53 penetrator/projectile don't match up with your suggested dimensions.

Im 1000% sure. Penetrator lenght in no way longer then 660mm.
I will post few photos.

 

[militarysta]

Photos:

IMHO no posibble longer then 660mm rod. Rather circa 640mm

less accurate (from Munster photo)

good picture from polish military press:

unkown

 

[Dinesh_Kumar]

The Gold Standard in Tank Guns remains the 120mm unit used on the Leapoard and Abrams M1A1. I'll try to post some info on its Development and Testing one of these days, when I get the time!

 

[methos]

IMHO no posibble longer then 660mm rod. Rather circa 640mm

I think that's somewhat questionable. When measuring the US' APFSDS or older German APFSDS (like DM13 and DM23), we can simply look at the images of cut-through projectiles or at drawings. So we know with a very high degree of correctness how long the penetrator should be.
However not all projectiles will follow the same pattern of construction of other APFSDS rounds. For example DM33 has a different internal construction, which lead to it's penetrator being only ~7 cm shorter than the overall projectile, while the length difference between penetrator and projectile in the American M829A1/A2/A3 rounds is ~10 cm or even more. One of the reasons is that the DM33 has a completely different tip construction, which worked better against some types of composite armour.

That there is the possibility to increase the overall penetrator length have shown different patents (including some from Rheinmetall) suggesting to change the tip construction or the way how the fins are connected to the penetrator. I cannot say the technology decribed in these patents has definetly been used on the DM53/63 ammunition, but OTOH I cannot say otherwise.

 

[icy2527]

Does anyone have some information about limit of APFSDS' length in T-64/80 type autoloader ?

 

[militarysta]

@UP yes, check previous pages.

EDIT:

ETs40 (T-64B)
T-6ETs43 (T-80U)
6ETs43-2C (T-64BM Bulat)
~710-730 mm

AZ serie (T-72 and clones) circa 640mm
AZ serie modernisated (T-90A, Rogatka, etc) circa 740mm

 

[militarysta]

Polish 120mm and one 125mm apfsds ammo - for Leopard-2 and PT-91, all is developmned in Poland in WITU.

 

[Dazzler]

@militarysta, @methos


norinco ammo,,,

 

[militarysta]

@UP ammo on photos is photoshoped so I can't rescale it and estimatous - unfortunatly not this time...