Armoured Vehicles Discussion Thread

[Shalav]

The longest recorded tank vs tank kill was a British Challeger firing a 3 burst HESH at an Iraqi T62 at a range of 5100 m. This was fired from a rifled cannon.

That said IIRC smoothbores have a greater range of ammunition available to them and impart greater velocity.

APFSDS, HE, MP-HEAT (this is a fin stabilised sub-calibre warhead), Canister (US M1A2 for AP use, chemical and sub-munition dispersion) etc.

OTOH rifled bores can also be used in the indirect fire mode - like artillery with HE.

Fin stabilised or spin stabilised, the idea is to stop the round from tumbling before it reaches the target.

Smoothbore or rifled depends on the users doctrine. The IA figured it needed a rifled cannon when defining the GSQR for the Arjun.

As a example of why this argument is futile consider below


-----
Compare the 1400 m/s for the MP-HEAT round for the L/44 M1A2 to the 1100 m/s for the HEATand about 900 m/s for the HESH round on L/55 Challenger.

Of course the MP-HEAT on the M1 is a sub-calibre munition and weighs about 60% of the normal HEAT round for the Challenger.

Then again HEAT is not a kinetic weapon so velocity on target is immaterial. Velocity is important for the HESH round as you want to give the munition time to pancake itself against the armour before detonation, hence HESH rounds are slower.

But then again MP-HEAT delivers about 60% of the chemical energy of the full calibre HEAT round.

See how this can go around in circles.

[KiranM]

Vina I hate to do this to you, but that was really sad really sad, no content and all bluster.

What an oxymoron!!

[Sanku]

Smoothbore or rifled depends on the users doctrine. The IA figured it needed a rifled cannon when defining the GSQR for the Arjun.

The GSQR is 20 years old. If IA was to write its wish list today I am certain it would opt for a smooth bore.
--------------------------------------

Apart from IA GSQR in general --

The rifled offers no advantages (apart from HES) but additional needless complexities -- it has been argued that Rifled is actually suboptimal for APFSDS and HEAT, hence the entire world has given up on it for tank gun.

Its actually as simple as that.

[putnanja]

Sanku, vina is absolutely right in his arguments, and unfortunately, apart from google links, I am yet to see similar technical/scietific explanation from you.

Adding a anti-spin collar is not "jumping through the hoops" to make APFSDS round fire from rifled bores. It is a very simple and straight-forward solution used for a long time and it doesn't make a shell any more complex.

The NATO forces adopting the rhinemetall gun is mainly due to economies of scale and commonality of ammo among various armies.

The fact that even Russia, the ones who first used smooth bore did not abandon rifled bore completely and were still trying it out on their new tank, shows that rifled gun is not as outdated as you want everyone to believe.

[Sanku]

Sanku, vina is absolutely right in his arguments, and unfortunately, apart from google links, I am yet to see similar technical/scietific explanation from you.

Vina thinks smoothbores are accepted because of fashion?

I provide google links because anyone can come here and pass hot air. Which is the BRF way. Back up your assertions with facts on the ground. Your say so is not good enough.

Adding a anti-spin collar is not "jumping through the hoops" to make APFSDS round fire from rifled bores. It is a very simple and straight-forward solution used for a long time and it doesn't make a shell any more complex.

Yet tons of google links point to the same. That it is a needlessly messy process. In addition rifling is a pain to maintain.

The NATO forces adopting the rhinemetall gun is mainly due to economies of scale and commonality of ammo among various armies.

They could have gone for a rifled gun for economies of scale too? Why didnt they? Especially when they were ALREADY on rifled to begin with.

Vina thinks its fashion? Your take?

The fact that even Russia, the ones who first used smooth bore did not abandon rifled bore completely and were still trying it out on their new tank, shows that rifled gun is not as outdated as you want everyone to believe.

Yes, rifled guns will be around for a long time. They have a specific role for example in artillery guns. People will play around.

However nothing changes the fact that everyone has opted for smoothbores in practice. TODAY (tomorrow something else may happen)

[Manish_Sharma]

The reason why I continued replying is not to educate you or to "enlighten" you on anything. You are simply beyond it. The reason is much larger.

The reason is this. BRF is a much wider audience and a lot of people, hopefully including someone in authority do read into this (they usually do, BRF oldtimers like Shiv etc say the audience that read all this sometimes simply unbelievable) .

For far too long, the Arjun has been a victim of total disinformation from "interested parties " , plainly ignorant people and literally village idiots who pass for journalists in this country. I can go back to mid eighties and quote from magazines of "quality" like India Today and all else quoting blatant falsehoods and disinformation. This is just another way of rebutting it with quality arguments to thinking people.

The "technical" arguments went on these lines.

1) The Arjun is a mis mash of foreign technology , ill integrated and wont work and "not indigenous"
Well, nothing can be further from the truth. It picks and chooses important susbsystems for world leading vendors. All leading Tank programs (be it US, Germany, France, UK, So Ko, Japan etc) went that route . Arjun is far more indigenous than the T90 / T72 which anyway is fully imported!.

2) The Arjun is "slow" cant fight in the deserts.. etc. etc.
Well, the Arjun has a lower ground pressure , has a higher power to weight ratio, has greater power reserve. The recent results prove it.

3) The Arjun is "too big" lacks "strategic mobility".
Well , the Arjun goes on the indian railways everywhre. The Army has operated tanks called Centurion a generation ago that is in the Arjun weight clas..

4) The Arjun has a "rifled gun" . So it cant fire 1) APFSDS 2) Missiles 3) Has lower muzzle velocity 4) Is outdated. This canard ,in addition to journalist village idiots was also spread for long by "Senior Army Sources" based on "fundamental design and physics".

This is what I wanted to answer in these long winded posts.

And BR has done a very nice job! Even common people "Data Entry Operator" category people like me know the truth behind the efforts that have gone into making "Arjun" and "Tejas" like indigenous products, not to mention the scuttling of these great efforts by our own people.

[putnanja]

The fact that even Russia, the ones who first used smooth bore did not abandon rifled bore completely and were still trying it out on their new tank, shows that rifled gun is not as outdated as you want everyone to believe.

Yes, rifled guns will be around for a long time. They have a specific role for example in artillery guns. People will play around.

However nothing changes the fact that everyone has opted for smoothbores in practice. TODAY (tomorrow something else may happen)[/quote]

Sunku, the new russian tank had rifled gun , and I am not talking about artillery here. So, if tomorrow, NATO decides to move to rifled bore, will you follow too?? The gun should be based on our requirement, and saying that everyone does the same ,and so do we doesn't make sense. There is a reason that the army asked for a rifled gun even though it had T-72s with smooth bore.

[Austin]

Which new Russian tank has rifled gun ?

[putnanja]

Which new Russian tank has rifled gun ?

None does at present, but the T-95 black eagle tank had initial plans of having a rifled gun

[RoyG]

The army wants the ability to fire HESH and penetration rounds.

Our rifled gun meets this requirement perfectly.

The fact that it is rifled hasn't been an issue for them.

So what exactly is the problem?

T-fans are now resorting to nitpicking.

Why bother convincing?

[Sanku]

Sunku, the new russian tank had rifled gun , and I am not talking about artillery here. So, if tomorrow, NATO decides to move to rifled bore, will you follow too?? The gun should be based on our requirement, and saying that everyone does the same ,and so do we doesn't make sense. There is a reason that the army asked for a rifled gun even though it had T-72s with smooth bore.

No Putanja you are missing the point.

Look at the following points for rifled guns for
1) APFSDS and HEATs are both suboptimal even after the rotating bands compared to smooth bores (in terms of slower speeds and aerodynamic issues dealing with band)
2) The presence of rotating bands create their own issues in design of tank shell.
3) The rifling itself tends to wear out sooner leading to more maintenance issues.

Given that the above two rounds are practical tank rounds the entire world has moved to those.The entire world.

And remember these folks started off with rifled guns, they had no reason to move away to smoothbores if they did not have a initial compelling advantage (as they broke from their legacy logistics)

The basic technical reasons + global trends of all tanks moving to smooth bores leads to a simple conclusion.

I personally dont understand whats the angst about this fairly simple statement.

[Vivek K]

What type of gun did the GSQR require?

[Sanku]

T-fans are now resorting to nitpicking.

Why cant you people see beyond fanboyism? Is this all the forum members understand, fanboy this or fanboy that?

This is a real debate on technical issues for a change, an engineering project is nothing but a 1000 nitpicks put together.

Grow up people.

[Karan M]

Sorry no you have provided no links. I am aware of most publicly available information on this issue,

Clearly, you are not. If you were you would not even have raised the below claim.

but I dont see some of your claims being buttressed, anyway lets leave it for a moment this is a generic statement that I made, if I disagree I will raise specific points to the discussion that I am presently interested in, which is why are we on a rifled canon. When the world has moved on.

As everyone else has informed you here, the Indian Army's specific requirement was for HESH rounds which are not available with smooth-bore cannons. HESH is devastating against structures such as bunkers and is equally effective against light vehicles (FSAPDS in both cases, can end up having limited utility).India faces a huge number of fortifications versus Pakistan, and the HESH is far superior to any other round in dealing with these.

Secondly, India had extensive experience with the excellent 105mm gun on the Vijayantas which was even retrofitted to the T-55 replacing the earlier Russian gun, and the Army liked its accuracy and firepower. Given both of these factors, the Arjun's gun was developed as a rifled gun.

Lastly, we have retained it because it is effective. The Arjun rifled gun with its FCS/Stabilisation has routinely out shot the T-72 and T-90 guns, so why wouldnt it be retained.

The rest of the world has moved onto 120mm smoothbore, because they dont want to invest in creating their own guns when Rheinmetall has a lockdown on the market and is willing to provide technology access for the right fee. With the huge number of Leopard 2's and Abrams made and sold worldwide, the 120mm smoothbore has become ubiquitous and adoption makes life easier for those countries which are willing to rely on third party ammunition and gun development.

That is not the case with India which pursues a stated policy of indigenisation.

BTW -- making statements bold is not shouting, just emphasis.

Posting in caps lock and bold is akin to shouting. Kindly desist. I am not blind and I can read your posts very well.

Mrinal you know, you do know a lot of stuff and I agree with you most of the time, but sometimes I wonder whether you really read what anyone else posts.

For example where did I say that there would be links for that claim? Considering that I have clarified that it is purely a question that I have raised here?

On what basis have you raised the claim, then? Consider, you have a gun that outperforms or at the very least equals a longer barreled gun fielded on your rival tank, it works perfectly well with current and required ammunition and is very well integrated with a sophisticated fire control system. Why change it?

Change/modify what is required in the Arjun over the longer term, not what works fine and will continue to work fine!

Fine, so if in actual conditions, the smooth bore and rifled are nearly similar in performance (your claim) combined with the fact that Smooth bores are easier to maintain, combined with the fact that the entire world has moved to smooth bore guns, tells us what?

Tells you nothing. First it is your claim that the rifled on the Arjun is more high maintenance than the one on the T-90. Tell us how many EFC it can stand, how many cycles the breech can withstand before it needs to be stripped and refurbished and how accessible it is for routine maintenance versus the complex gun plus autoloader combination on the T series tanks which is a pain to access!

Claims the sort of which you are making are meaningless. It is akin to saying that since most of the world does not do x, b should not do y. The reality is that India had the option to pursue smoothbore gun development when the Arjun was redesigned to match a frontline western tank, and chose not to pursue that option.

That smooth bores are a good way to go perhaps?

Not really. See above.

Just to let you know 125 mm tank gun that you talk about is the current Russian 125 mm tank gun. If a 120 mm smooth bore can do a good job, there is no reason why an Indian 125 mm can not do a better job? In addition it can be designed to also use the T 90 ammo (apart from Indian ones too)

You continue to make assertions based on flawed claims. If India is to develop a new gun then why a 125 mm smoothbore and not a 120 mm? Secondly, it makes little sense to design the gun to use the T-90 ammo because the T-90 ammo is currently from Russia, because the T-90 tank does not have a ballistic computer which can accept any Indian round! So you should be saying the T-72 ammunition, as currently produced. Now your proposed gun cannot use the OFB 125mm ammo either because it is two piece, think for a second, what it does to rate of fire. You are making absolutely no sense here. The T-72 and T-90 style tanks use the Russian autoloader which first loads a round, and then a propellant charge, because it made it simpler for an autoloader to handle (less weight, size) to squeeze into the hull of the tank. Incidentally, thats also one of the huge flaws in the T series tank as once the rounds run out in the autoloader, manually loading the rounds is a pain, and the autoloader adds extra complexity, and if hit will blow up bigtime.

But if you note I am not a diameter nazi. If 120 smoothbore offers better ammunition choices so be it.

What better ammunition choice? Take a look at the number of rounds available and the types for 105mm rifled. The same will be available for the 120mm if required. Here is your desired HEAT round.
http://www.eas.gr/index.php?lang=en&sec=7&cid=205
The Israelis will sell you APAM as well. Others will even work with your for 120 mm FSAPDS or even other rounds. There is no issue here apart from one you are making up.

All that is fine, and I am aware that Indian manufacture does not necessarily mean that ToT is done.

However the reports indicate that the T 90 ToT absorption did happen and Indian made tanks are being produced, 10 tanks were made in 2009. Maybe your data point is older and the ToT has now moved on?

Here are some links which support the same (ToT issues resolved)
http://indiadefenceonline.com/810/india ... d-shortly/

After a gap of one year, fifty T-90 tanks will be rolled out from India under licensed production following the resolution between India and Russia over the issue of transfer of technology. Indian defence officials have indicated that assurance from Russia has been received regarding the timely execution of defence deals including the T-90 tanks.



Followed by the actual production and induction
http://www.siliconindia.com/shownews/In ... 60608.html

After a delay of one year, the first batch rolled out of the Heavy Vehicles Factory (HVF) here. The batch of 10 tanks was inducted into the army at a function in Avadi by Minister of State for Defence M.M. Pallam Raju.



So as per public information, ToT has happened and Indian made T 90s are being made.

Arnab has already covered this point.

Furthermore, if you want to see the issues behind T-90, reported recently from somebody who should at least know about this aspect..

http://www.indiandefencereview.com/2010 ... tself.html

From December 2009, Mrinal Suman Maj Gen rtd.

# In cases involving transfer of technology, most vendors disregard terms of contract and start playing truant for extracting additional benefits. Instead of transferring know-how to facilitate indigenous production, they adopt delaying tactics to get additional orders for fully built up equipment. Russia delayed providing critical technologies and vital components for the production of T-90 tank in India for the same reason. Vendors exploit India’s urgency to make up deficiencies for unethical gains.

# With confirmed supply orders in hand, many unprincipled vendors attempt to cheat by supplying sub-standard material. Russia tried to pass refurbished Tanguska air defence systems to India for new equipment. Most of Krasnopol precision ammunition sold turned out to be dud. There is hardly any equipment that fulfills promised performance parameters. Every trick is tried to dupe India. Even much touted fire control system of T-90 tanks failed to perform as per the claimed performance parameters.

When an Indian Army guy, that too one who is no fan of the PSU setup goes hammer and tongs at the Russians, it really reflects the state of affairs.

[Viv S]

In 1985, when the Army revised the GSQR to 120mm capable of firing HESH rounds, most of the world's modern tanks were ALREADY operating a smoothbore main gun. Except for the Challenger 2, for reasons of commonality with NATO allies, switching to a smoothbore, nothing has changed today.

[chackojoseph]

What type of gun did the GSQR require?

Rifled. And it bettered the T-90 smoothbore.

[Karan M]

In 1985, when the Army revised the GSQR to 120mm capable of firing HESH rounds, most of the world's modern tanks were ALREADY operating a smoothbore main gun. Except for the Challenger 2, for reasons of commonality with NATO allies, switching to a smoothbore, nothing has changed today.

Exactly.

Further, the UK is not just switching because of reasons of commonality per se, but also because of costs. The UK is finding it increasingly hard to maintain a proper tank building establishment and wants to reduce costs wherever possible. The idea is that they'll switch the guns and pay acquisition and integration costs upfront, but recoup over the long term as the Germans, Americans etc will keep making 120mm rounds for the 120mm smoothbore which they can then use. Not to mention they will keep developing the gun further as well, and the UK says bye bye to this expenditure. Sounds good in practise but the current expenditure is already a problem so the UK is going slow after some hype around the topic a few years back.

India cannot rely on this strategy. Will the US for instance sell India M829A3 rounds or the Germans the latest (from Janes) DM63, with transfer of technology so that we can make as many as we want. Will we get detailed access to upgrade the 120mm gun whenever we want.

For India, building on the perfectly functional 120mm rifled makes ample sense.

For the future, say another ten years down the line, we can do what the Germans did, and put a longer redesigned 120mm gun to keep it current against then threats. For now, with some iterative expenditure on ammunition development, the gun is perfectly fine.

[Anujan]

Look at the following points for rifled guns for
1) APFSDS and HEATs are both suboptimal even after the rotating bands compared to smooth bores (in terms of slower speeds and aerodynamic issues dealing with band)
2) The presence of rotating bands create their own issues in design of tank shell.
3) The rifling itself tends to wear out sooner leading to more maintenance issues.

Given that the above two rounds are practical tank rounds the entire world has moved to those.The entire world.

And remember these folks started off with rifled guns, they had no reason to move away to smoothbores if they did not have a initial compelling advantage (as they broke from their legacy logistics)

The basic technical reasons + global trends of all tanks moving to smooth bores leads to a simple conclusion.

I personally dont understand whats the angst about this fairly simple statement.

It is because we are moving round and round and you are arguing as though it is clear that a rifled gun is inferior. It is NOT!

1a. APFSDS has *no* loss in speed if you add slip rings to the round. I repeat *no* loss. The slip ring assembly itself is a minute fraction of the weight of the projectile and the sabot. Arjun APFSDS has muzzle velocity of 1650m/s (from DRDO publication). That seems fast enough for me.
1b. The entire slip ring/Sabot assembly is DISCARDED after firing. Pray tell me where the "aerodynamic issues" came from?
1c. The effectiveness of HEAT rounds is not in any way related at all to their velocity. RPGs with slow projectiles do just fine.
1d. On the contrary, Arjun seems to show more accuracy than T90. Blame it on the ammo, FCS, sights or the gun, the point remains that all claims to loss of velocity, aerodynamic issues & complexity in manufacturing is purely speculation.

2. What issues? Could you point us to actual figures? Arjun has conducted firing of more than 5000 rounds! and this is by the user and does not include testing. During the last comparative trials, more than 500 rounds were fired. During AUCRT more than 1000 were fired. If there is one issue *not* reported by anyone, it is complaint about reliability of Arjun's ammo.

3. Where did you get this gem of an information from that the rifling wears out? Tank rounds are different than bullets, they have a semi combustible cartridge case and lined shell - there is no metal on metal friction in the barrel! Do you know that the life of much vaunted smoothbore L55 gun is about 250 rounds? Yes thats true. 250 rounds! DRDO techfocus on Arjun printed that the barrel life is more than 500 rounds!

NATO moved to smoothbore because most of europe's ammo is made in germany & it makes economic sense. Well the whole world did many things. Like move to 5.56mm rifles. The Europeans have moved to bull pup designs. Nobody except for the Russian bloc have double hulled subs. What is the point?

The issue is
a. Do we have some unique requirements
b. Does our product meet those requirements

[RoyG]

T-fans are now resorting to nitpicking.

This is a real debate on technical issues for a change, an engineering project is nothing but a 1000 nitpicks put together.

Grow up people.

Sorry for stating the obvious.

Indeed it is time for all of us to grow up.

How about fitting the Arjun Turret on a T-90 chassis and calling it T-Ex2?

Surely that would bring commonality to the fleet of tanks!

[sivabala]

Choices are to be done based on requirements not on fashion. If other did something we have analyse before repeating the same.(Remember look before you leap)
APFSDS and HEAT works for both anti-tank and vehicle roles. HESH works against for fortified defensive formations also.

Smooth bore european tanks are expected to face off numerous armored small Russian tanks and BMPs.
But Indian tanks are expected to cut through the defensive fortifications in gujarat,Rajasthan, Punjab.
As a commander what choice will you make.(Smooth bore- APFSDS, HEAT. Arjun-APFSDS, HESH)

IF the accuracy is not lost in smooth bore why would Gemrans go for a long barrelled gun ?

Bigger the diameter of projectile, more the drag. So for a given charge , sufficiently smaller the diameter, distance traveled is farther. If 120 mm can do a job why go for 125 mm which needs more energy for the same distance to be travelled.
Farther the distance from which we destroy enemy fortifications safer our fleet will be.

Autoloader saving a manpower. There are a number of advantages of another crew. The extra crew can help speed up the reload, and help with repairing the damaged tank. more than that its faster to shoot the enemy manually than with the autoloader. The time saved might save the tank itself in crucial times. In that case, the cost of a tank exceeds the cost of the additional man crew itself.

Commonality can be achieved by replacing the T-72 and T-90 turrets with Arjun's turrets with our rifled as already pointed out and this way we need not import ammunition from any other country.

[Surya]

well said RoyG

So lets move with Tank Ex and more and we will have commonality

[RoyG]

well said RoyG

So lets move with Tank Ex and more and we will have commonality

Suryaji,

Tank-Ex is inferior to T-90. I am speaking of Tank-Ex Mark II. No need for continuation...We need to work with a more contemporary model which has major upgrade potential for the future! That said, Tank Ex Mk II will sport the ultra heavily redesigned chassis of the T-90 which makes the Arjun and T-72 diesel its tracks! This will give adequate crew comfort and feature an AC unit along with hardened electronics. Moreover, Tank Ex Mk II will feature the hydromoronic suspension system for utmost smoothness. Oh and how can I forget the weight reduction which will allow it to fly through the air and squash pakistani soldiers as they flee in fear. The gun can also be replaced with the 125mm Smoothbore since the 120mm Rifled falls off after 500 rounds. What were those DRDO chaps thinking adopting that ancient design?! The 125mm will also allow the Tank Ex MkII to fire the deadly INVAR missile which hasn't suffered a single failure unlike the LAHAT! Our infrastructure can also handle this beast unlike the Arjun which has become bloated from all the estrogen it's been fed. It is common for peri-menopausal tanks to throw fits of rage and sometimes beat up other tanks on the battlefield so don't pay any attention to the latest comparative trial. It isn't indicative of Arjun's general performance. Soon the arjun will become menopausal and unworthy of standing in the presence of the FMBT with its glorious 152!

[nachiket]

Smoothbore or rifled depends on the users doctrine. The IA figured it needed a rifled cannon when defining the GSQR for the Arjun.

The GSQR is 20 years old. If IA was to write its wish list today I am certain it would opt for a smooth bore.
--------------------------------------

The rifled gun was because the IA specified that they wanted the tank to fire HESH rounds. Has that requirement changed? Why? And how do you know?

[nachiket]

My wish list for Arjun

1 ) New 1,500 HP engine to compensate for the increased in weight by couple of Tons
2 ) New 125 mm Smooth Bore which can bring in standardization of ammo that T-90,72 and Arjun can fire
3 ) ERA , Active Protection System and BMS system
4 ) Ability to fire F&F type ATGM from its MG
5) Get rid of one guy from that tank ( 3 crew ) and go for a full auto loader .

Austin could you clarify something for me?
The T-90 tank ammo is two-piece unlike the Arjun. Since two-piece ammunition cannot be loaded manually (quickly enough that is), you say we can fit the T-90 style autoloader onto the Arjun as well. So now we lose the Arjun's current ability to fire Long-rod penetrators and gain the Auto-loader's disadvantages (as mentioned by Mrinal a few posts back). And since the T-90 can't fire Indian ammo, the only way to achieve commonality is if the new Arjun starts using Russian ammo as well. What exactly do we gain with all this? Especially since there have been no complaints about the capabilities of the Arjun's current gun from the Army.

[niran]

Soon the arjun will become menopausal and unworthy of standing in the presence of the FMBT with its glorious 152!

why not increase it to 155 and solve the need for Artillery.

[vina]

Soon the arjun will become menopausal and unworthy of standing in the presence of the FMBT with its glorious 152!

why not increase it to 155 and solve the need for Artillery.

Well, that is EXACTLY what the Russians were trying to do..Problem is that it is for "themselves" of course. 152mm is the Russian artillery standard. So they wanted to put a 152 mm gun for "commonality" with artillery. So that brings us the question.. If a tank gun has to fire a 152mm artillery shell, must it be rifled or smooth bore ?

Err. The Rodina has chosen a RIFLED gun for it's tanks to serve from 2020 to 2070. All Hail. So Rifled Gun is the way forward in the 21st century. The smooth bore is so "outdated" and 20th Century.. So everyone must go rifled gun of course.. (why, coz the Russians have done so, thats why and they must be right of course).. Err. But when Arjun has a Rifled Gun in 2010 (20 years before Rodina) it is "outdated" and so 19th/20th Century of course.. (why, because, the Rodina has only smooth bore guns as of TODAY.. if you are ahead of Rodina, you are "outdated"..only the Rodina has the right to he "ahead", why because they are always right )..

[RoyG]

Soon the arjun will become menopausal and unworthy of standing in the presence of the FMBT with its glorious 152!

why not increase it to 155 and solve the need for Artillery.

Sure, why not?

[Austin]

The idea that Russian Future Tanks will use Rifled Gun is very speculative , infact the news that it may use 152 mm gun is all speculation , the T-95 program is classified one so any information that it would use rifled gun or not is not a verified claim.

If Rian news is to be believed ( an unverified claim ) it uses smooth bore 152 mm gun link

[niran]

The idea that Russian Future Tanks will use Rifled Gun is very speculative , infact the news that it may use 152 mm gun is all speculation , the T-95 program is classified one so any information that it would use rifled gun or not is not a verified claim.

If Rian news is to be believed ( an unverified claim ) it uses smooth bore 152 mm gun link

the very idea of a classified T95 program is speculative, i.e. no one knows whether it is vaporware or just plain Hot-gass-ware.

since self styled Gurus are propagating their wish list, here is my humble wish for FMBT
- Get a 155 mm main gun and devise a system to use the recoil to make the FMBT leaps
across ditches, pitches, ponds, lakes, while with 125 mm secondary machine gun exterminate the running pacquise
just as a Frog leaps and gulps its prey.

[Austin]

Austin could you clarify something for me?
The T-90 tank ammo is two-piece unlike the Arjun. Since two-piece ammunition cannot be loaded manually (quickly enough that is), you say we can fit the T-90 style autoloader onto the Arjun as well. So now we lose the Arjun's current ability to fire Long-rod penetrators and gain the Auto-loader's disadvantages (as mentioned by Mrinal a few posts back). And since the T-90 can't fire Indian ammo, the only way to achieve commonality is if the new Arjun starts using Russian ammo as well. What exactly do we gain with all this? Especially since there have been no complaints about the capabilities of the Arjun's current gun from the Army.

Well since we are obsessed with Long Rod there is a new autoloader available on T-90M that can fire the long rod and a 125mm Gun with better characteristics.

No body is saying the 120 mm Guns are bad , some one even claimed that the 120 mm Rifled Gun is superior in many aspects could be , but the advantage of having a 125 mm smooth bore gun on Arjun is you can have a standardisation of ammo , the range and type of ammo Arjun can fire will be standardised across the ~ 3000 plus tank fleet.

IMO the standardization is itself a big advantage instead of operating a 120 mm MG and another 125 mm MG. The larger the number of Arjun in the service the greater is the benefit from standardising it with the rest of T fleet.

And what is the obsession of using Russian ammo , half of the defence equipment uses Russian Ammo either imported or Lic built.

How ever if the Army feels it be 120 mm Rifled Gun on Arjun and no change needed then so be it , the IA has a better grip on its need then we all do.

[Austin]

the very idea of a classified T95 program is speculative, i.e. no one knows whether it is vaporware or just plain Hot-gass-ware.

Really , if you cared to read the ria link it quotes from the horses mouth , it is a classified project

"The work on the project has been conducted for many years. If the government gives us a 'green light' we will exhibit the tank at the [Russian Expo Arms 2010] arms show in Nizhny Tagil this summer," general director of the Uralvagonzavod plant Oleg Siyenko told RIA Novosti in an exclusive interview.

"I cannot disclose the characteristics of the tank, but I can assure you that we have met all the requirements put forward by the military," he said.

[vina]

but the advantage of having a 125 mm smooth bore gun on Arjun is you can have a standardisation of ammo , the range and type of ammo Arjun can fire will be standardised across the ~ 3000 plus tank fleet.

No. You wont. Problem is your older T72/T90 cannot fire the new "long rod" that you claim the T-90M has, unless you put the additional autoloader and the new gun on the entire existing fleet!. That is a massive upgrade, and will also require new FCS. If you do induct the T90M, it will be a standalone "island" with all sorts of incompatibility between the newer stuff and the older "legacy" stuff in the T72 /T90.

The larger the number of Arjun in the service the greater is the benefit from standardising it with the rest of T fleet

On the contrary. This is a fallacy. The larger the number of Arjuns in service, the greater the economies of scale that kick in for Arjun (right from manufacturing, ammo, maintenance, logistics, etc) and the per unit cost will drop and you can justify a separate Arjun specific ecosystem on it's own.

It is ONLY when you stop with a very small fleet like 124 tanks, it will be very hard to justify an Arjun ecosystem and a convincing argument can be made that such a small fleet adds little value to justify separate /dedicated ecosystem, so lets scrap it.

Now you know where the "Natasha" argument comes from and all the talk about stopping it at 124 orders and to build a future "FMBT" (which of course can be a 20 year project ,which will not threaten the current T90 and which can be sabotaged later if and when it comes in due course via buy imported Russian T-95/Black Eagle/Ding Dong) while building 1600 T90s.

Those arguments must be clearly recognized for what they are. An attempt to kill the Arjun on economic grounds, now that the arguments of killing it via organzitional resistance, false inneundoes on technical grounds and plain sabotage(the summer trails engine failures were absolute and clear sabotage,though I doubt it will EVER be acknowledged publicly) have fallen flat and the Arjun has clearly demonstrated superior performance.

[Anujan]

the advantage of having a 125 mm smooth bore gun on Arjun is you can have a standardisation of ammo , the range and type of ammo Arjun can fire will be standardised across the ~ 3000 plus tank fleet.

Standardization at what cost? Russkies are not allowing the modification of T90 FCS to accommodate local ammo, DRDO even has a tender out to reverse engineer the T90 FCS to accommodate OFB manufactured ammo! So for the near future we will be importing T90 ammo and *if* we succeed in reverse engineering the FCS (big IF), then *maybe* (big MAYBE) move to OFB ammo for T90 (if the trials pan out). And maybe (big MAYBE) it wont piss off the Russkies and they will allow us to do so.

AND given all that you want Arjun to standardize on 125mm smoothbore for what? So that it may use the *imported* T90 ammo?

a) Who is going to modify Arjun FCS to use Russie manufactured ammo?
b) Arent we shooting ourselves in the foot if we go out of the way to modify the Arjun so that we are *forced* to import ammo?

[vina]

What better ammunition choice? Take a look at the number of rounds available and the types for 105mm rifled. The same will be available for the 120mm if required. Here is your desired HEAT round.
http://www.eas.gr/index.php?lang=en&sec=7&cid=205
The Israelis will sell you APAM as well. Others will even work with your for 120 mm FSAPDS or even other rounds. There is no issue here apart from one you are making up.

Yes Mrinal . The range of ammo for the 105mm L7 and derivatives (still in service in variety of platforms, including the brand new Stryker for instance) is pretty large. However the HEAT round you posted here seems to be the fin stabilized General Dynamics round licensed version by the Greeks . This is probably not what our "Google challenged" friend was looking for.

What I meant was round like the "Obus à Charge Creuse de 105 mm Modèle F1" (OBUS- G) French round that the AMX-30 fielded. It really was the gold standard of it's day. Check out the AMX 30.

Specifically about the round.

One of the most unique features of the AMX-30 was the Obus à Charge Creuse de 105 mm Modèle F1 (Obus G) HEAT projectile and its main gun,[37] the Modele F1, a monoblock steel 105-millimeter (4.1 in) cannon.[42][43] HEAT warheads suffer when spin stabilized, a product of rifled barrels,[44] causing the French to develop the Obus G[34], (Gresse).[15] This projectile was composed of two major parts, including the outer shell and a suspended inner shell, divided by ball bearings. This allowed the projectile to be spin-stabilized, and therefore more accurate than a normal fin-stabilized HEAT-round, while the inner shell did not move, allowing the warhead to work at maximum efficiency. The warhead, containing 780 gram hexolite,[45] could penetrate up to 400 millimeters (16 in) of steel armour and was effective against tanks at up to 3,000 meters (3,300 yd). As it combined a good accuracy with a penetration that was independent of range, it has been considered an "ideal round" for its day[34]

Think of it..3000 mts anti armor capability back in it's day. Why the current T-90 cannot do it as of today with it's APFSDS round. It is a pity that the French and others too standardized on a smooth bore and hence a 120mm version of this kind of weapon could possibly never be developed. With Arjun, we have that kind of chance. If we field a 120mm version of this (no need to re-invent anything, the French would gladly sell us the design and we could scale it to 120mm quite easily), and probably have a tandem warhead on it to defeat ERA kind of armor that is common place today, we could have a gun based stand off anti armor that is probably good for 6 to 7 kms given the modern fire control systems of today! That is a plus which we should explore I think. Also if we want to put a passive Bofors Excalibur like seeker system and EFP top attack capability, we could possibly have a shell that can engage at a good 8 to 10 kms indirect fire tank attack capability giving missile like capabilities at far cheaper prices.

All that can come about only if we continue investing in the platform and develop further . Doctrines can be developed around it and capabilities enhanced. However if we let the Natashas have their way and let Arjun be killed it will deal an irrecoverable blow to any future armor development in India. No questions about it. If we want independent development and capabilities, the Arjun should be fielded in sufficient quantity , like say 500 to 750 units.

[Bheem]

My discussion with some chaiwalla/person:-


1. Even with driving band, a Sabot fired from rifled barrel will have 'some' spin but this spin is good. It makes the round more "accurate" and less likely to bounce/glance off the target tank.


2. The rifled barrel can also fire HE round and can be used as "quasi" self propelled artillery for long range shelling.


3. Russians adopted a smooth bore for short ranged fast fired sabot round to meet their deficiencies in metallurgy. The world continued to use 105mm rifled tank gun till eighties till they switched to 120mm smoothbore. UK realised that smoothbore is just fashion while rifled barrel continues to give better performance. India followed suit.

[Sanku]

As everyone else has informed you here, the Indian Army's specific requirement was for HESH rounds which are not available with smooth-bore cannons.

Why does any one need to tell me this? My questions was "Is the requirement for HESH rounds reason enough to continue for rifled?"

Secondly, India had extensive experience with the excellent 105mm gun on the Vijayantas which was even retrofitted to the T-55 replacing the earlier Russian gun, and the Army liked its accuracy and firepower. Given both of these factors, the Arjun's gun was developed as a rifled gun.

Obviously, I have said that myself about 10 times. If only people would read.

Lastly, we have retained it because it is effective. The Arjun rifled gun with its FCS/Stabilisation has routinely out shot the T-72 and T-90 guns, so why wouldnt it be retained.

And who was talking about Arjun/T 90? We are talking about a smoothbore for arjun vs a rifled for Arjun.

Is that really so hard to get

With the huge number of Leopard 2's and Abrams made and sold worldwide, the 120mm smoothbore has become ubiquitous and adoption makes life easier for those countries which are willing to rely on third party ammunition and gun development.

And why did they opt for smoothbore?

That is not the case with India which pursues a stated policy of indigenisation.

Irrelevant strawman.

Posting in caps lock and bold is akin to shouting. Kindly desist. I am not blind and I can read your posts very well.

But you dont. That is the fact.

On what basis have you raised the claim, then? Consider, you have a gun that outperforms or at the very least equals a longer barreled gun fielded on your rival tank, it works perfectly well with current and required ammunition and is very well integrated with a sophisticated fire control system. Why change it?

I have already mentioned the reason 1001 times, but either folks dont read or dont want to read.

Change/modify what is required in the Arjun over the longer term, not what works fine and will continue to work fine!

Very funny, what works fine

Tells you nothing. First it is your claim that the rifled on the Arjun is more high maintenance than the one on the T-90.

Tells me you actually dont read my posts.

The reality is that India had the option to pursue smoothbore gun development when the Arjun was redesigned to match a frontline western tank, and chose not to pursue that option.

Can I see some supporting data for that claim?

Just to let you know 125 mm tank gun that you talk about is the current Russian 125 mm tank gun. If a 120 mm smooth bore can do a good job, there is no reason why an Indian 125 mm can not do a better job? In addition it can be designed to also use the T 90 ammo (apart from Indian ones too)

Hmm more flawed comments based on flawed understanding.

You continue to make assertions based on flawed claims. If India is to develop a new gun then why a 125 mm smoothbore and not a 120 mm?

If you had actually read. That was also an option I suggested.

Secondly, it makes little sense to design the gun to use the T-90 ammo because the T-90 ammo is currently from Russia,

Huh, for 1600 tanks if we need ammo. Sooner or later we will make the same in India. Maybe the exact same shell. The fact it originated in Russia has nothing to do with it.

Now your proposed gun cannot use the OFB 125mm ammo either because it is two piece, think for a second, what it does to rate of fire.

So does Chally without a autoloader. In fact three parts

http://en.wikipedia.org/wiki/Challenger_2

(The main armament ammunition is thus described to be "three part ammunition", consisting of the projectile, charge and vent tube.) Contrary to speculation, the use of three-part ammunition rather than the NATO standard single part cased ammunition does not reduce the rate of fire of Challenger 2; in fact, a loader can often sustain a higher rate of fire than tanks firing single part ammunition, with or without auto-loaders.

You are making absolutely no sense here. The T-72 and T-90 style tanks use the Russian autoloader which first loads a round,

Two part charges have nothing to do with autoloaders. They are two separate entities. There can be unitary round autoloader and there can be two part ammo for manual loading.

This fixation with T 90/Arjun is the cause of such narrow straitjacketed thinking.

The Israelis will sell you APAM as well. Others will even work with your for 120 mm FSAPDS or even other rounds. There is no issue here apart from one you are making up.

What happened to your love for Indian rounds, dissapers as soon the you need to purchase from Isralies but not Russians.

Arnab has already covered this point.

And I covered his point.

# In cases involving transfer of technology, most vendors disregard terms of contract and start playing truant for extracting additional benefits. Instead of transferring know-how to facilitate indigenous production, they adopt delaying tactics to get additional orders for fully built up equipment. Russia delayed providing critical technologies and vital components for the production of T-90 tank in India for the same reason. Vendors exploit India’s urgency to make up deficiencies for unethical gains.

So, we already know it was delayed, by a year?

# With confirmed supply orders in hand, many unprincipled vendors attempt to cheat by supplying sub-standard material. Russia tried to pass refurbished Tanguska air defence systems to India for new equipment. Most of Krasnopol precision ammunition sold turned out to be dud. There is hardly any equipment that fulfills promised performance parameters. Every trick is tried to dupe India.

Even much touted fire control system of T-90 tanks failed to perform as per the claimed performance parameters.

When an Indian Army guy, that too one who is no fan of the PSU setup goes hammer and tongs at the Russians, it really reflects the state of affairs.

But the TI is not Russian? It is French? The Major Gen is talking of All suppliers, not only Russians. In anycase what does that have anything do with the matter at hand. Yes imports are fraught with such issues. We already know that. Basic stuff.

But we are talking of something else altogether arent we.

[Sanku]

Boss the ENTIRE WORLD moved to smooth bores. The Germans were on rifled when the moved to smooth bores.

Barring 50 odd Arjuns and 200 odd Challenger 2, 20,000+ Front line MBT of all countries moved to Smoothbores.

For commonality you say? But for commonality they could have continued to stay rifled, they were already rifled? Why didn't they?

And whats the commonality between Soviet and Western block tanks? Why are they both Smoothbore?

Just because Germany made a kickass smoothbore Gun? Why didnt they make a kick ass Rifled gun. They did make kickass rifled guns in the past too?

Oh yes I forgot because it fashionable

Instead of looking at the real world try and divert the topic by Arjun vs T 90 false fight.

[Bheem]

Edited and reposted

My discussion with some chaiwalla/person:-


1. Even with driving band, a Sabot round fired from rifled barrel will have 'some' spin which is around 5-10% of the normal spin but this spin is good. It makes the round more "accurate", helps in cleaner seperation of sabot and makes it less likely to bounce/glance off the target tank. Now the stinger, even the KE round fired from smoothbore barrel spins as the spin is enduced by the fins and as the range increases so does the spin. Zero spin is very bad for accuracy.

2. The rifled barrel can also fire HE round and can be used as "quasi" self propelled artillery for long range shelling. With smoothbore the accuracy, range and explosive contents decreases considerably for HE, smoke, phosporous, anti-personal, anti-helo rounds etc.


3. Russians adopted a smooth bore for short ranged fast fired sabot round to meet their deficiencies in metallurgy. The world continued to use 105mm rifled tank gun till eighties till they switched to 120mm smoothbore. UK realised that smoothbore is just fashion while rifled barrel continues to give better performance. India followed suit. Now UK does not have money to develop next gen of rifled barrels so it "might" retro fit / upgrade its tanks with German smoothbore barrels/ammo as its own plants have closed down years back.

[Sanku]

1. Even with driving band, a Sabot fired from rifled barrel will have 'some' spin but this spin is good. It makes the round more "accurate" and less likely to bounce/glance off the target tank.

This is a good reason why chaiwalla reports are so derided, because that piece of wisdom is not supported by ANY open source material AT ALL.

3. Russians adopted a smooth bore for short ranged fast fired sabot round to meet their deficiencies in metallurgy. The world continued to use 105mm rifled tank gun till eighties till they switched to 120mm smoothbore. UK realised that smoothbore is just fashion while rifled barrel continues to give better performance. India followed suit.

The Germans who have always been THE tank makers shifter to smoothbores because it was fashion?

And so did US for its 10000 M1 tanks because it was fashionable

And the Brits with a grand total of 400 Chally 2 (which have also given up their foolishness) were the only intelligent people?

Wow.

-----------------------------------------

Meanwhile all the Pundits here going on about Autoloader and Two part shells and what not are unaware of basics of Chally 2 and Le Clerc

http://en.wikipedia.org/wiki/Leclerc

The Leclerc is equipped with a GIAT (Nexter) CN120-26 120mm smoothbore cannon. This cannon is theoretically capable of firing the same NATO standard 120mm rounds as the German Leopard 2 and US M1 Abrams, but in practice only custom French-produced ammunition is issued. The gun is insulated with a thermal sleeve and has an automatic compressed air fume extraction system instead of the usual bore evacuator. The Leclerc has a unique autoloading system which was specifically designed for it, and reduces the crew to three by eliminating the human loader. The turret of the Leclerc was designed around the auto-loading system in order to avoid the problems common to other tanks with an autoloader. The Leclerc autoloader allows a rate of fire of 12 shots per minute and holds 22 rounds of ready ammunition; it can accommodate up to five different types of ammunition at once, although like most autoloader systems it cannot change ammunition types once a round has been loaded. The most common types are the armour piercing fin-stabilised discarding sabot (APFSDS) with a tungsten core and the high explosive anti-tank (HEAT) round. There are 18 other rounds available for reload. A Leclerc tank can fire while traveling at a speed of 50 km/h on a target 4,000 metres away. The gun is 52 calibres long instead of the 44 calibres common on most tanks of the Leclerc's generation,[1] giving the rounds a higher muzzle velocity.

Bottom line Canon, auto loader, and shells are three different parts of design. They can be mixed and matched depending on what your design goal is.

There is no golden rule which says 2 part shells means auto loader, or auto loader mean two part shell. And none of this has anything to do with smooth bore vs rifled.

And none of the above has ANYTHING to do with FCS, or stabilization.

The final accuracy of a TANK is a function of canon + ammunition quality + stabilization + fcs.

[rohitvats]

All this talk of standardization of main gun around 125mm and the compatibility of using the same ammo is pure hogwasg. And the numbers thrown around are pure distilled BS. Consider these:

(a) 3,000 tanks with 125mm main gun - What every one forgets is that Russians developed a modified auto-loader for T-90 to allow it to fire "their" latest APFSDS with longer projectiles. While no one knows whether IA has these Russian APFSDS, by chance if we do, it means the T-72 cannot fire the same ammo as T-90 (at least the APFSDS). So, there goes the commonality and 3,000 number out of the window.

(b) Commonality of Ammo - This takes the cake. How can there be commonality of ammo when T-72 and T-90 fire two piece ammo while the Arjun (even with 125mm gun) fires/will fire unitary round? And before anyone jumps in with "auto-loader" thing for Arjun, please keep in mind that only western tank with auto-loader uses a bustle mounted one and not the carousel (and for good reasons - which, monetary situations permitting, even the Russians wanted to move away from) and hence, can fire the unitary round. Or unless, we deliberately want it to fire 2-piece ammo with inherent limitations.

(c) 125mm Unitary ammo - Does anyone manufacture 125mm unitary ammunition? No, and why? Because no 125mm gun exists which can take the unitary round. So, what we need next is new technology+manufacturing plant for 125mm unitary rounds for Arjun? So much for economies of scale with "3,000 other tanks" which will continue with their 2-bit ammo.

(d) Russian APFSDS growth potential - From what I gather, the maximum length of APFSDS permissible is 635mm which they have achieved with their DU round. There is talk of 740mm APFSDS but the same requires modification to auto-loader of T-90. Compare this with 780mm for western APFSDS. Now, considering the fact that Arjun does not suffer from any auto-loader induced limitation (even when you give it bustle mounted one) for the length of its ammo, should it be restricted to fire "shorter" Russian/Indian/Israeli APFSDS for the sake for commonality with T-90?

And oh! before anyone jumps in with T-90M upgrade and aft-mounted aut-loader, if you observe carefully, the pics show two-piece ammunition in the cassette. So, in case we want unitary round for 125mm gun on T-90 and Arjun, who will porduce the same? Russians? I guess not? Why you ask? Simple, numbers/economies of scale? No one will produce unitary 125mm rounds for T-90M unless the same represents a very large market. Which it is not and no one knows the future numbers. Russians for sure are not going to manufacutre this round - what is the number of T-90M or Burlak expected in Russian service? They'll do fine with their 2-piece ammo. So, guess who will be left holding the hat? Yes, the mighty Indian Army.

So much for commonality.