Tank Guns and Ammunition

[hest]

Also I put in doubt penetration value for M332, this round has l/d ratio lower than DM43, value of which is given as 320-350 mm RHA for 60 degrees, 2000 m range, in some sources even lower, as OFL120G... so it is most likely incorrect or just wrong advertisement, in reality being around 600 mm for normal.

 

[militarysta]

What is strange, or suspicious is that KMW insisted on imposing it's conditions, they had chosen the weakest round and fired from great range on purpose, when it doesn't make sense because on firing range such test is normally carried out from 200 m, it is obvious that they wanted comfortable for them situation. According to greek report it is 2000 m.

1) what is difrence between circa 500 and 2000m in Vdrop and in the same time in theory in penetration?
2) what is decrease velocity on 1000m?
answer those question.
In fact the difrence for modern long rods is marginal as I remember (circa 50-100m/s)
For You both answers are hidden here:
http://www.witu.mil.pl/www/biuletyn/zeszyty/20050096p/61.pdf

Współczesne pociski podkalibrowe z odrzucanym sabotem, stabilizowane brzechwowo, odznaczają się małym spadkiem prędkości
pocisku na torze lotu, a wynika to z geometrii budowy pocisku (dla najnowszych konstrukcji światowych wynosi on ok. 50 m/s na odległości 1000 m). Przy prędkościach początkowych rzędu 1500E1800m/s daje to duŜe prędkości uderzenia w cel na odległościach nawet powyŜej 2000m.

In fact diffrence in Vdrop between for example 500m and 2000m will be only 75m/s Seems to be very small and insignificant value -itn't it?

CL3143 is M322 or M332 ? Those last aren't different rounds ?

No, Greek test was on M322 -it's bout those round:
http://www.imi-israel.com/vault/documents/120mm m322 apfsds-t_nt-001_drafrt-0043.pdf
Israeli 120mm APFSDS - AFV Forum - Tanknet

I already understood that it is not the same, the point is how could you talk about M332 pressure value and somehow claim it would achieve higher energy, without knowing value in function of temperature, or paramethers in barrel. Only new propellant gives such energic characteristics while conventional decreases pressure after chamber, this applies to both CL3143 and old Svinets. As shown, amount of propellant and it's energy, pressure in chamber is comparable while being caliber and lenght of 2A46 greater, so it is unsastained to claim CL3143 is more energic.

Methos is good in counting MJ -ask Him. We have all data for Swedish ppj95, and most for Sniviets (3BM46) and even on fovanov page for Lekalo. More or less if Sniviets/Lekalo have the same propelant like M322/ppj95 then value will be bigger for M332 -when intitiali we have bigger MPa value then in both Soviet rounds. Propably only M332 and Lekalo will be close togethere.

Great. But this shows what are maximum values gun can support, not specific DM53 performance, which depends on temperature.

Not exatly, in typical avarage conditions values will be like posted on draw. problems whit DM53 whare on very hot or very cold climate -almoust non existing in western/central Europe. So if you are talking about fight on Sahara or North pole - then maybe, but non in typical western Europe conditions - in that case avarage value will be as on draw.
BTW: I delete some infos from that draw from obvious reson

On graphic you can see that it does not surpass 550 MPa in chamber well after 20 degrees and reaches what is maximum velocity, 1700 m/s and chamber pressure after 40. DM 63 is not able to surpass 1650 m/s...

Those draw from waffen muntione etc is ads how insensitive propelant charge can be cool, and good, etc. I post here draw how in reality look this in modern rounds - MPa in chamber is lower then in barrel. That was in DM53 case, and it's a;moust sure that the same is on DM63 case.
If DM63 have circa 550MPa in chamber then it will have circa 780-800MPa in barrel. It,s big difrences.
Velocity is not most important factor. In fact all is based on quattro factors: sabot mass, penetrator diamensions (lenght, diameter, mass), muzzle and MPa value. Combination off all this will give good penetration. Only big muzzle vill give nothing.

with DM53 barrel life is only 150-200 rounds, worse than 1970s soviet level.

liar, liar pants on fire...
Kamppanzer heute und morgen, s.142, s.146
for 2A46 instruction gives 157 APFSDS shoots, in fact in DDR tanks it was 87 APFSDS shoots befor gun must be replaced (about T-72M1 so in late 1980s)
And again WITU saources:

34Z przeprowadzonych badań wynika,że lufa armaty czołgu T-72 (PT-91) ulega zużyciu po oddaniu 200 - 300 strzałów pociskami podkalibrowymi bojowymi, a lufa czołgu Leopard2A4 wytrzymuje ponad 700 strzałów

translate: From reseercht it's seems that barrel in T-72(PT-91) need replace after 200-300 APFSDS shots, while Leopard-2A4 barrell is able to windstand (without replace) more then 700shoots.
But thos is about Konstrukta barrel from Slovakia.

And here is another good pdf about this:

THE WEAR OF 120 MM TANK GUN BARRELS
Abstract:
The paper presents analysis of problem with lifetim
e of gun tubes. The article
shows influence of different factors (geometrical c
haracteristics, internal ballistic, material
properties) on wear of gun barrel during firing. Th
e article consists also criteria for the state
evaluation of gun tubes for different kind of weapo
ns. Results of tube examination after firing
using Polish ammunition PZ541 are attached.

http://www.witu.mil.pl/www/biuletyn/zeszyty/20080107p/95.pdf

Here you have life time for L-44 barrel and DM-53, DM63, M829E3 and M829A3 (whit L-44) and trening rounds).

CL3143 and old Svinets this is not the case.

Check IMI page about M322 propelant charge.

Svinets howewer is fired from barrel 6 meters long vs 5.3 and of greater caliber.

But M322 is mucht longer, have smaller diameter, and have biger MPa in chamber (670Mpa) while max chamber MPa value for 2A46M4 is circa 550-600MPa (on btvt).

DM63 is not able to approach maximum value, it's maximum is around 10 degrees, under 600 MPa in chamber, 1650 m/s.

Draw shown avarage in european conditions. This 550MPa is for chamber. In barrel value will be circa 230MPa bigger. Even If you give "only" 500MPa then in barrel for modern propelant charge You have circa 750MPa for DM63 as the worst possible scenario. In optimistic case it will be over 800/850MPa...

I do not understand how they "rejected".

Based on known now sources (it can be changed by new sources) Soviet developers in erly 1990 had turn in to long monoblock rods -propably homogenous - like Sniviets (3BM46) and Lekalo (3BM42M). While in Sniviets from DU it's not suprise after shorter but monoblock 3BM32(DOI 1985) then Lekalo planned as DOI in circa 1992/1993 is long monoblock rod while 3BM42 have compltly diffrent build. So in some resons Soviet developers hed dacide to completly change idea how penetrator should looks. I supose they are looking for better not whorse round, so they had choose better not whore options -yes?

 

[militarysta]

Also I put in doubt penetration value for M332, this round has l/d ratio lower than DM43, value of which is given as 320-350 mm RHA for 60 degrees, 2000 m range, in some sources even lower, as OFL120G... so it is most likely incorrect or just wrong advertisement, in reality being around 600 mm for normal.

Very good source in two part article about Merkava Mk.IV give for M322 circa 650mm RHA at 2000m. It have sense.

 

[hest]

1) what is difrence between circa 500 and 2000m in Vdrop and in the same time in theory in penetration?
2) what is decrease velocity on 1000m?
answer those question.
In fact the difrence for modern long rods is marginal as I remember (circa 50-100m/s)
For You both answers are hidden here:
http://www.witu.mil.pl/www/biuletyn/zeszyty/20050096p/61.pdf

In fact diffrence in Vdrop between for example 500m and 2000m will be only 75m/s Seems to be very small and insignificant value -itn't it?

It is significant. Apart from loss of energy, it affects negatively another aspects. Increase in penetration of high angle of incidence, against angled plate, composite armour diminishes linearly with loss of velocity, as well as performance against semi-active armour arrays which effect can increases as projectile incides with closer to optimal, slower working velocity, this is the case for example with bulging armour.

They surely knew about this difference, in some degree same as polish producers.. otherwise tell me what sense would it make to perform test at such great distance in proving ground where it is comfortable standart to test in about 200 m. They wanted most optimal situation for them.

No, Greek test was on M322 -it's bout those round:
http://www.imi-israel.com/vault/documents/120mm m322 apfsds-t_nt-001_drafrt-0043.pdf
Israeli 120mm APFSDS - AFV Forum - Tanknet

So CL3143.

Met

hos is good in counting MJ -ask Him. We have all data for Swedish ppj95, and most for Sniviets (3BM46) and even on fovanov page for Lekalo. More or less if Sniviets/Lekalo have the same propelant like M322/ppj95 then value will be bigger for M332 -when intitiali we have bigger MPa value then in both Soviet rounds. Propably only M332 and Lekalo will be close togethere.

The only data which you have is maximum chamber pressure of 670 MPa (at high temprerature) which tells nothing, what temperature, what average. On this aspect Snivets is not different.

Neither it is logical that M322 with same propellant than Svinets would have greater energy, with same pressure you would produce greater force on bigger surface, caliber, and you have longer 2A46 gun. Knowing this I do not get where you sustain your idea. And it is dubious that round of 80-90s would have such energic propellant instead of conventional.

Not exatly, in typical avarage conditions values will be like posted on draw. problems whit DM53 whare on very hot or very cold climate -almoust non existing in western/central Europe. So if you are talking about fight on Sahara or North pole - then maybe, but non in typical western Europe conditions - in that case avarage value will be as on draw.
BTW: I delete some infos from that draw from obvious reson

That drawing gave value in condition that initial chamber pressure was >700 MPa, it reflected maximum value. Overall for DM53 it depends on temperature, as you saw in graphic it only approached that value under high tempreature, on average temperature it does not reach 550 MPa in chamber.

Problem is not only in extreme conditions, but abrasive propellant as pressure increases and is maintained notably after chamber

Those draw from waffen muntione etc is ads how insensitive propelant charge can be cool, and good, etc. I post here draw how in reality look this in modern rounds - MPa in chamber is lower then in barrel. That was in DM53 case, and it's a;moust sure that the same is on DM63 case.
If DM63 have circa 550MPa in chamber then it will have circa 780-800MPa in barrel. It,s big difrences.
Velocity is not most important factor. In fact all is based on quattro factors: sabot mass, penetrator diamensions (lenght, diameter, mass), muzzle and MPa value. Combination off all this will give good penetration. Only big muzzle vill give nothing.

In graphic they have shown velocity, which reflects energy, in function of temperature and max chamber pressure, this obviously takes all increase after chamber, etc into account, see again

With DM63 propellant round will be provided with maximum energy in 10 degrees under 550MPa in chamber, for all case it will not surpass 1650 m/s.

liar, liar pants on fire...
Kamppanzer heute und morgen, s.142, s.146
for 2A46 instruction gives 157 APFSDS shoots, in fact in DDR tanks it was 87 APFSDS shoots befor gun must be replaced (about T-72M1 so in late 1980s)
And again WITU saources:

translate: From reseercht it's seems that barrel in T-72(PT-91) need replace after 200-300 APFSDS shots, while Leopard-2A4 barrell is able to windstand (without replace) more then 700shoots.
But thos is about Konstrukta barrel from Slovakia.

Yes, projectiles were the issue for gun, not much it's construction, it also depends on production quality (and in export T-72 it was also different..). You know those models are from 70s even if used in 80s ? By that time already new model was in service. What's interesting is that Rheinmettal, manufacturer of propellant gives for DM53 barrel life of 130-200 rounds which is comparable with 70s ammunition For DM33, DM63 it gives 400-600 rounds, 2A46M5 is >500 rounds. These are guarantees from producer even if they can be somewhat different in ocasions.

And here is another good pdf about this:

http://www.witu.mil.pl/www/biuletyn/zeszyty/20080107p/95.pdf

Here you have life time for L-44 barrel and DM-53, DM63, M829E3 and M829A3 (whit L-44) and trening rounds).

This uses the same source from producer, DM33, DM63 400-600 rounds, DM53 130-200 .

Check IMI page about M322 propelant charge.

It does not say anything in particular, neither about penetration.

But M322 is mucht longer, have smaller diameter, and have biger MPa in chamber (670Mpa) while max chamber MPa value for 2A46M4 is circa 550-600MPa (on btvt).

... ? This MPa is for what, maximum temperature ? Average in function of temperature is hardly superior, while there is not any evidence it uses unconventional propellant. And again, energy is in function of pressure, caliber and lenght.

That MPa reflects characteristics of ammunition and it may be true (even thought Mango seems to exceed it under higher temperature) but for 2A46M1,2 models.

Draw shown avarage in european conditions. This 550MPa is for chamber. In barrel value will be circa 230MPa bigger. Even If you give "only" 500MPa then in barrel for modern propelant charge You have circa 750MPa for DM63 as the worst possible scenario. In optimistic case it will be over 800/850MPa...

In graphic you have for DM53 and DM63 chamber pressure in function of temperature, and maximum energy, velocity which can be achieved in all conditions.

Based on known now sources (it can be changed by new sources) Soviet developers in erly 1990 had turn in to long monoblock rods -propably homogenous - like Sniviets (3BM46) and Lekalo (3BM42M). While in Sniviets from DU it's not suprise after shorter but monoblock 3BM32(DOI 1985) then Lekalo planned as DOI in circa 1992/1993 is long monoblock rod while 3BM42 have compltly diffrent build. So in some resons Soviet developers hed dacide to completly change idea how penetrator should looks. I supose they are looking for better not whorse round, so they had choose better not whore options -yes?

Hadn't they changed dimensions they probably would stick with similar solution, but situation is much different, because deformation effects on short, thick and rigid round and in penetrator with greater elongation require different construction, and alloy has different material properties and there are more elements involved in penetration process, so to say they turned back to simple monoblock is not that correct. it is not less complex, that for sure.

Very good source in two part article about Merkava Mk.IV give for M322 circa 650mm RHA at 2000m. It have sense.

It is probably advertisement or wrong interpretation of value. In view of comparable and more advanced rounds, DM43.. it is possible but only for 60 degrees, for normal it is less.

 

[volna]

IMHO,maybe the Svinets-1,2 are the downgrade versions of the Lekalo with shorter penetrater to fit T-72/90's autoloader.And how do you guys think?

 

[Austin]

Can Svinets-1,2 can be fired from Indian T-90 Tank Guns as Indian T-90 uses 2A46M/M1 Gun , that would probably need a change in autoloader itself as well.

 

[hest]

Svinets-1 has active part lenght of 632 mm with penetrator lenght of 558 mm, so it can be employed with standart autoloader and propellant. Svinets-2 active part is around 740 mm and penetrator lenght 660 mm, this requires modifications.

 

[volna]

Svinets-1 has active part lenght of 632 mm with penetrator lenght of 558 mm, so it can be employed with standart autoloader and propellant. Svinets-2 active part is around 740 mm and penetrator lenght 660 mm, this requires modifications.

So the Svinets-1 you meant is the old 3BM-46 round?I really confused.

 

[hest]

No, Svinets-1 is new round, dimensions of which are similar to previous Svinets.

 

[volna]

So this one is Svinets-1,and the Svinets-2 has a longer penetrater?
[

 

[hest]

This round has a lenght around 680 mm, so it is probably Svinets-1. Yes.

 

[volna]

So the Svinets-1 and Svinets-2 are two different rounds with different length and material of their penetrator?

 

[hest]

Apparently yes.

 

[Austin]

So the Svinets-1 and Svinets-2 are two different rounds with different length and material of their penetrator?

Gur Khan mentioned to me that one round is DU and other is Tungsten round , though the exact dimension of rounds is not reveled officially.

 

[militarysta]

German 120mm ETC:




Soon I will post more interesting stuff

TOW-2B warhed, and part of its trials:

 

[militarysta]

Who says that KE penetrator can't have ramjet engine?

Some interesting infos from that text can be takens -for example DM33 velocity decarase and others. More or less- there is possible to made ramhest APFSDS penetrator whit constans velocity at long distance.

 

[militarysta]

Interesting abour SC and others:

 

[Bhadra]

@militarysta

Can poland design ammunition to defat German armour and on the other side to take care of ultra modern Russian armour..

obviously you can not !!

 

[militarysta]

Where is point?
They will be bought bought very modern APFSDS german munition, ant this will solved most problems.
BTW: even 3Bm22 can kill M1A2, or T-90A It's only "tactics" problem.

 

[militarysta]