Armoured Vehicles Discussion Thread - Jan 12, 2012

[member_22539]

^ Thats news to me, is that true?

[Singha]

afaik
Diehl used to supply the tracks , which is indigenized now with someone locally supplying the rubber parts which was not earlier
Renk supplies the gearbox and transmission
MTU supplies the engine

not aware of Rheinmetall being in matrix unless one of the above is a subsidiary. I thought they only made gun systems. Arjun gun is derived from a french giat design allegedly.

arjun mk2 will likely have a remote weapons stn for commander (T90 can direct and fire its HMG from inside) with a HMG and some form of optics (T90 has none). useful for high angle fire in urban scenarios where the coax MG cannot engage and beating off infantry attacks. btw does Arjun have a coax MG ?

[Kanson]

^ yes, it is.

[alexis]

Are there methods to impart a spin on round fired from a smoothbore cannon? Against tanks, smoothbore (AFPDS/HEAT) is a better (cheaper) weapon while against buildings and light skinned vehicles, rifled (HESH) seems to be better.

[nachiket]

Against tanks, smoothbore (AFPDS/HEAT) is a better (cheaper) weapon

I don't know what you mean by this exactly. The Arjun's rifled gun is perfectly capable of firing APFSDS rounds. It just requires the sabot to be modified. While the sabot spins, the KE penetrator itself does not. OFB makes the ammo. OFB does not currently make any HEAT round for the Arjun's gun though.

[vina]

While the sabot spins, the KE penetrator itself does not

No, even the sabot doesn't spin. What does spin is the driving band alone. Google around for the APFSDS ammo pic for the Royal Ordnance L7 105mm gun, which was the "universal" gun of it's day , ie the Rheinmetall 120mm in the 105mm world .

This gun is still used today in brand new vehicles such as the Stryker! A classic gun. The Arjun 120mm is just an evolution of this I think. We did produce the L7 gun in India.

[Sanku]

Are there methods to impart a spin on round fired from a smoothbore cannon? Against tanks, smoothbore (AFPDS/HEAT) is a better (cheaper) weapon while against buildings and light skinned vehicles, rifled (HESH) seems to be better.

Sabots are not used against light skins or other such. A smooth bore uses many other types of rounds for a range of targets like Helicopters, light skin vehicles and such like

Take a look here
http://www.inetres.com/gp/military/cv/weapon/M256.html

HESH was the old solution, it is not needed anymore. Better solutions to HESH exist.

MPAT (M830, M830A1), MPAT-OR (M908) round target effects:
Depend on chemical energy and not striking velocity.

Used primarily against lightly armored targets, field fortifications, and personnel. Are secondary armor-defeating ammunition.

Due to slower muzzle velocity, these rounds are not as accurate as APFSDS rounds at ranges beyond 2,000 meters.

Rounds arm approximately 60-100 feet from the muzzle of the gun. Because of the shape and metal components of the projectiles, however, this ammunition remains effective at ranges of less than 100 feet.

Heavy Armor. Because of a relatively small explosive warhead, MPAT effectiveness against heavy armor (tanks) is limited to attacks from the side and rear. Mobility kills of heavy armor can be achieved when fired at from these orientations (especially if tracks and or road wheels are struck); however, the vehicle armament is likely to remain operational.

Light Armored Vehicles (LAVs). The heavy nose of the MPAT projectile makes it extremely effective against LAVs. Vehicle kills can be achieved with an impact on varying locations on the hull or (if so equipped) the turret. Mobility kills can be achieved if the wheels or tracks are struck, and it is likely that a road wheel or track impact will also produce penetration of the hull structure. MPAT is effective when it impacts targets from perpendicular to highly oblique, but will function with a reduced reliability when striking excessively oblique surfaces (nearing that of a graze impact).

Bunkers. The heavy nose of the MPAT projectile makes it extremely effective against earthen, timber, and or sandbag bunkers with the projectile "burying" itself into the bunker structure before warhead detonation. When this occurs, the projectile detonation produces not only lethal effects to personnel within, but a highly-destructive effect to the bunker structure itself.

Buildings. MPAT is effective against buildings with wooden walls over 1 inch thick. Impact against a thinner wall structure (plywood sheathing without striking supporting members) may produce only a small hole as the projectile passes through the wall without detonating. Impact against a supporting structure (roof rafter, wall stud) causes detonation of the warhead and a subsequent hole and lethal fragmentation effects to personnel located inside. Impact against concrete walls yield holes of about 24 inches in diameter, but reinforcing bars embedded within the concrete are not likely to be cleared from the hole, unless struck directly. One MPAT round normally creates a breach hole in all but the thickest masonry construction - a single round demolishes brick veneer and wood-framed constructions. The round is large enough to displace enough spall to inflict casualties inside a building.

Helicopters - M830A1. The M830A1 MPAT, when switched to the "A" or "air" mode, is effective against attack helicopters because of its proximity switch, which can produce mission abort kills without actually impacting the aircraft. The design of the proximity switch is such that if the projectile (set in the "A" mode) is fired against a helicopter, and is on a direct impact flight path, the projectile warhead will not function in the proximity mode, but will be detonated when the projectile strikes the target. If the projectile, however, strikes lightly armored parts of the structure (such as windows or the aluminum skin of the aircraft), it is likely to pass directly through the aircraft without detonating. Impact with heavier structures, such as the engine or transmission components, will cause detonation of the warhead.

Concrete Obstacles - M908. The M908 HE-OR-T projectile, because of its steel nose, is effective against large concrete obstacles. This effectiveness comes from the projectile's striking the face of the obstacle and penetrating several inches before the warhead is detonated. This penetration fractures the concrete obstacle from within, breaking it into smaller blocks, which can be cleared with an M9 Armored Combat Earthmover (ACE). A concrete block 6 feet in diameter and 6 feet long is broken up into rubble, which can be cleared by a tank equipped with a bulldozer blade.

[vina]

HESH was the old solution, it is not needed anymore. Better solutions to HESH exist.

Ah.. So let us see what the "better solutions" are and why

MPAT (M830, M830A1), MPAT-OR (M908) round target effects:
Depend on chemical energy and not striking velocity.

Used primarily against lightly armored targets, field fortifications, and personnel. Are secondary armor-defeating ammunition.

And as Sanku Maharaj says. take a lokeee

Take a look here
http://www.inetres.com/gp/military/cv/weapon/M256.html

And what do you see in the pictures. All the rounds (not just the APFSDS, but the HEAT and the MPAT and other , which are really HEAT derivatives) are SUB CALIBER with a nice sabot wrapped around the round and a fin sticking out in the rear taking the space which could otherwise have gone to the propellant!

Now compare that with the picture of a HESH and HE-Frag round fired from a rifled gun and you immediately notice the bulbous ogival nose that is FULL caliber and obviously packs a far greater amount of explosive than the sub caliber round.

But.. Sanku Maharaj's link itself says, that it is Chemical Energy and not velocity that these rounds depends on. But by some strange logic, the round that packs much less chemical energy becomes "better" than the one which packs more !
Also notice this.

Due to slower muzzle velocity, these rounds are not as accurate as APFSDS rounds at ranges beyond 2,000 meters.

Ah, the "better" solution, does not really work even half way decently beyond 2000 meters, while a rifled gun is accurate to 6/7 kms easily.. Yup. shorter range is "better"

Oh well, the round that packs LESS explosive and is LOWER ranged, becomes by some abracadabra, Lahori Logic, Madrassa Math and Shanghai stat, all rolled into one, "BETTER" . What can I say, ask the Maharaj!

This link which Maharaj posted clearly underlines what I have been saying. The smooth barrel is specialized into Tank vs Tank at 2 kms or less only. It is a compromise in every other role. What works for AmirKhan , Nato and Soviets, with fully mechanized armor and infantry, attack helis, etc, and optimized to either run through the Fulda Gap or stop the massed hordes of tanks and optimized for that role wont work for us. These

We need a multi role tank, able to give fire support to infantry, assault built up positions, give close support to infantry and also take on , bust and out run and outgun the enemy armor. For that, I do think the rifled gun was an excellent choice.

Frankly, the amount of rubbish I have read,put out by the detractors for a long time on the Arjun , the chief among them on the lines that the Arjun gun is "obsolete" because, it couldn't fire an APFSDS and a Missile and the Warsaw Pact and NATO went smooth bore was held as "proof" and this included senior army types and also Ajai Shukla in the "pre reformed" and unvarnished "beer buddy of generals" version 1 avatar!

Ignorant/motivated politicking on "cant fire sabot rounds and missiles" has been firmly silenced (after all, any fool can check the fact it does on YouTube) and it is time to put to rest the other rubbish on "better" because the Americans and NATO went for it and supposed "superiority"

Look at the efforts the Isrealis have put in to get the traditional bunker busting and anti infantry and fire support capabilities (after Lebanon) that the tanks always had since WW-I, but lost that significantly when they went smooth bore ,via newer ammo! That capability is very important in an urban and asymmetric kind of environment. Thank goodness we made a good technical choice early there. The GSQR writers and the DRDO must be thanked for their foresight on this.

[keshavchandra]

@kunal biswas
A video on Arjun MK2 at defence exp 2012.....
One thing is clear that in Arjun the back shock/thrust which a tank gets after a round fire seems very less. Its really good for its crew during war, to retain long.
see At 1.01 min. in this vedio.

[Sanku]

Vina, your "what the 99% of worlds tank do and what India and 500 challys need is different" would even have been a excuse before Arjun decided to switch to smooth bore.

I dont know why you still keep insisting the world is flat

Now compare that with the picture of a HESH and HE-Frag round fired from a rifled gun and you immediately notice the bulbous ogival nose that is FULL caliber and obviously packs a far greater amount of explosive than the sub caliber round.

You know if you are going to take the childish logic that the amount of explosives packed is the only criteria of a shell being better. Then I have a better proposition for you, use 500 mm canons full of explosives

For those who can handle more complicated trade-offs of role/weight/ease of use/canon life etc can read this

On changing nature of tank ammunition.

http://www.thefreelibrary.com/Changing+ ... a096696884

Goes to show why HESH is now a dinosaur and requirements met by HESH earlier in 60s are being met by a whole host of better smart solutions.

In particular read the various types of HE rounds (non HESH) that exist and the roles they play in tank battles.

[vina]

Vina, your "what the 99% of worlds tank do and what India and 500 challys need is different" would even have been a excuse before Arjun decided to switch to smooth bore.

Well, the videos that the folks posted here on mods that are going into MKII feature the same gun as far as I can see! . Unless of course you so clairvoyant that you already see MkIV and V and probably a future tank that is also named Arjun, I think we should go with what is there in front of our eyes!

[Sanku]

Vina, your "what the 99% of worlds tank do and what India and 500 challys need is different" would even have been a excuse before Arjun decided to switch to smooth bore.

Well, the videos that the folks posted here on mods that are going into MKII feature the same gun as far as I can see! . Unless of course you so clairvoyant that you already see MkIV and V and probably a future tank that is also named Arjun, I think we should go with what is there in front of our eyes!

Ignorance is not a PoV. Read up on DRDO statement about developments in progress to move to smooth bores. There was sufficient discussion around that on this thread with me doing a victory lap and all that.

You are being really painful you know. First you wont inform yourself of the developments, then you will continue to claim what ever was true in 1960 is true today with total confidence.

Please, lets get real.

[vina]

On changing nature of tank ammunition.

http://www.thefreelibrary.com/Changing+ ... a096696884

. It is better titled as Changing BACK nature of tank ammo!

To quote from your own book.

Without many of the personnel involved appreciating or liking the fact, the main battle tank is reverting to its original role, that of being a mobile protected gun platform. As tanks evolved historically, the main opponent of the tank emerged as other tanks; therefore, they became the primary targets to be engaged. Entire ammunition loads of many battle tanks were devoted to armour penetration in some form or another, with little or no provision made for other natures (that is what the rifled to smooth bore switch is. both primary and secondary ammo as Anti Tank!). That situation has now been altered, as high explosive projectiles are once again becoming familiar to tank crews, along with other ammunition novelties. (indeed it is. Once you went smooth bore, you have to make do with the best of what you have and hence new ammo, making the best out of a suboptimal choice)

Blunt-nosed Heat fin-stabilised projectiles are fired at low muzzle velocities and are thus prone to side wind and other in-flight influences so may not be particularly accurate other than at short ranges. .haa haa. but we are spin stabilized and NOT fin stabilized like the smooth bores! Hesh, also known as high explosive plastic (Hep) by the US Army and others, is frequently not to hand as many nations have chosen not to adopt the type, usually on perceived ammunition safety grounds. On the other hand, many armed forces, such as those of Britain and Pakistan, have always highly regarded Hesh for its long-range accuracy and on-target effects. More on this later.

In particular read the various types of HE rounds (non HESH) that exist and the roles they play in tank battles.

Ah.. So what does your book say on that.. Let us see.

There is also the advantage that the provision of HE enables, at times, the host tank to act as a mobile artillery platform.

This was exactly the role for which the South African Denel 105 mm HE-T round was developed, to be fired from 105 mm L7/M68 series tank guns. During the South African border campaigns of the 1980s, armoured columns supported by tanks often operated deep within what was then enemy territory. Towed or other artillery was frequently at a premium during such operations, so if artillery support was needed it repeatedly had to be provided by the tanks. Although much of the HE fire provided by the South African Olifant (Centurion) tanks was delivered at direct fire ranges, it was possible to engage indirect targets up to 10,000 metres away .

But. But. Royal Ordance L7 is a RIFLED gun JUST like the 120 MM of the Arjun!! So what you are really saying that the rifled gun tanks provide artillery support upto 10KM away , per your own book! In an earlier post you said that the smooth bore tank cannot provide effective fire beyond 2KM!

Despite this by some convoluted logic, you still insist that smooth bore firing secondary ammo is better than the secondary ammo of a rifled gun , despite everything you posted saying exactly the opposite .

[Sanku]

^^^ I should have known you will quote selectively and totally out of context make a hash of it.

I only hope there are people who do not turn every discussion into a ideological battle ground and an opportunity to spew diatribe.

For the likes of you, who quote selectively let me quote some more from the link I posted.

This is what the selective quoting honest Vina left out (the section just after what he posted)

Armies with artillery assets rarely need tanks to deliver indirect fire but they do need to back up soldiers on the ground, often at very short ranges. HE projectiles are therefore becoming increasingly more commonplace; even if few newly developed examples are yet available.

Sorry Vina, your pathetic flight of fantasy punctured in nearly the next paragraph of your selective quote.

Here, the former Warsaw Pact nations have the advantage over their Nato and other Western counterparts in that they have always regarded 100, 115 and 125 mm HE as practical, all-round projectiles with numerous applications. They have long been able to deploy HE as a (relatively) low cost means of demolishing obstacles or knocking holes in walls for infantry to crawl through. They can also deal economically with soft vehicle and comparable high combat value targets. There is also the advantage that the provision of HE enables, at times, the host tank to act as a mobile artillery platform.

Warsaw pact nations? Your diatribe against smooth bores being a Soviet fad that all other idiots of the world blindly copied?

It appears that Warsaw pact could have a effective multi-role platform with smooth bores -- and they did not use HESH

Horror horror.

Read it all, the article, its fun and instructive. and in about 3 pages of write up, talks of HESH only for two paragraph in passing.

[vina]

It appears that Warsaw pact could have a effective multi-role platform with smooth bores -- and they did not use HESH

Dude. This is beyond belief! The Warsaw pacts CAN have an "effective" multi-role platform .. note they DONT have it currently, the IA T series (other than the L7 gunned T-55s probably) don't definitely ,with the Sabot and HEAT rounds they have, and they WILL have a far less than rifled gun capability IF they go and buy the new Isreali and other HE ammo!

The rifled gun on the other hand ALWAYS had this capability (making a HE round for the Arjun will be a piece of laddu, all you have to do is put a thicker shell casing for fragmentation and a different fuze, like that south African round you posted) and a HE shell fired (now, HE of all kinds is HESH is bread and butter artillery stuff) will be far far superior than any equivalent a smooth bore can field (will carry far higher ammo to a far greater distance and lot more accurately)

If you are taking out fortifications, what if the opposition have a Konkurs/Milan/Tow kind of system that can hit you at 4 to 6kms or so and hence out range you, because your weapons are limited to 2kms or so,you are a sitting duck, unless you call in artillery support or air support! Now that is not a problem for Khan or the Soviet Union, but for us, it can be crippling. Heck, even S.Africa, the country of Denel and their famous artillery, per your book faced artillery shortages, imagine India!

With a rifled main gun, you can take out such things and engage from a stand off distance and flatten that place and take out the vehicles! In fact, the IA should simply go for the "Karna" upgrade on the T-72 chassis that we licensed, by putting a bustle mounted autoloader version of the Arjun gun and turrent, take the newer systems like engines and ERA from the T-90 and tell the Russians to take a walk and bring the much needed modernization on the T-72 fleet and stop producing the additional 1500 or whatever T-90.

If we do that , we will have a unique and very optimized for our environment main gun and armament solution. In fact, the IA/DRDO, whether by accident or design, were singularly focused in this part of the specs, not taken in by "fashion" elsewhere, knew exactly what they wanted and nailed it. And indeed, now the rest of the world is coming around to recognizing the need for similar capability.

[Sanku]

It appears that Warsaw pact could have a effective multi-role platform with smooth bores -- and they did not use HESH

Dude. This is beyond belief! The Warsaw pacts CAN have an "effective" multi-role platform .. note they DONT .

No Vina that was my polite way of saying you are wrong. Since you clearly do not understand politeness -- let me tell you. You are wrong. Warsaw pact countries do have a effective overall tank platform -- and they are based on smooth bores -- check the article I quoted, I had posted the specific section too, but you just wont read, wont you.

Here, the former Warsaw Pact nations have the advantage over their Nato and other Western counterparts in that they have always regarded 100, 115 and 125 mm HE as practical, all-round projectiles with numerous applications. They have long been able to deploy HE as a (relatively) low cost means of demolishing obstacles or knocking holes in walls for infantry to crawl through. They can also deal economically with soft vehicle and comparable high combat value targets.

Rest of your post is SIMILAR pure fiction not backed by an iota of evidence in real world.


Stop making things up, rifled guns on tanks are a legacy of the time sabots were not found, once sabots were made, rifling on tanks was meaningless. All the requirements on tanks are easily met very effectively by SABOTs + HE WITHOUT disadvantages of rifiling and no need to use a very limited HESH but instead use a catch all smart HE round.

Welcome to 21st century, we can discuss HESH in army history thread if you so want.

[RoyG]

The 120mm rifled gun on the Arjun can fire sabot, HESH, HEAT, and laser guided missiles. Moreover, this gun has been developed within the country. How exactly is a rifled gun of this type meaningless?

[vina]

How exactly is a rifled gun of this type meaningless

Because Sanku Maharaj Ji thinks so ?

Oh well. He does have reading comprehension problems, especially when the references he posts say exactly the opposite of what he claims supports his view !

[Sanku]

How exactly is a rifled gun of this type meaningless

Because Sanku Maharaj Ji thinks so ?

Oh well. He does have reading comprehension problems, especially when the references he posts say exactly the opposite of what he claims supports his view !

Well Vina's comedy aside

1) No one said the gun on Arjun is meaningless, where did that come from?

2) The discussion was on HESH and Rifled guns on MBT in general tank design and not for a specific tank.

3) The advantages of a smooth bore gun are well understood, now that Indian Mil-Ind complex has necessary know-how, they are shifting to smooth bore for Arjun.

So pretty soon, Arjun should have a spanking new Smoothbore (if you ask me, that should be done ages ago)

[Anujan]

once sabots were made, rifling on tanks was meaningless. .

Actually that is not true and mixes cause with effect. Objects of high length to diameter ratio cannot be spin stabilized and they need tk be fin stabilized. longer thinner penetrators needed fins for stabilization and a way to be fired as sub caliber rounds. that is why sabots were developed - a way to hold and fire sub caliber rounds from guns. sabots would also be needed to fire penetrators from rifled guns because they are sub caliber there too. On the other hand fat short projectiles still need spin stabilization. Pray tell me how sabots have subsumed rifling?

The debate whether HESH is needed at all and consideration of gun similarity is valid. But saying somehow sabots have rendered rifling useless is nonsense and completely meaningless.

[Sanku]

once sabots were made, rifling on tanks was meaningless. .

Actually that is not true and mixes cause with effect. Objects of high length to diameter ratio cannot be spin stabilized and they need tk be fin stabilized. longer thinner penetrators needed fins for stabilization and a way to be fired as sub caliber rounds. that is why sabots were developed - a way to hold and fire sub caliber rounds from guns. sabots would also be needed to fire penetrators from rifled guns because they are sub caliber there too. On the other hand fat short projectiles still need spin stabilization. Pray tell me how sabots have subsumed rifling?

The debate whether HESH is needed at all and consideration of gun similarity is valid. But saying somehow sabots have rendered rifling useless is nonsense and completely meaningless.

Well yes, the Sabots have been around since gunpowder and canon days so saying that sabot makes rifling unnecessary is clearly not precisely correct.

To be exact I should have said, "the development of APFSDS made the rifling irrelevant/meaningless"; however I was hoping that the context of the discussion would have made it obvious anyway.

With respect the discussion must be seen in its context you will be able to see the meaning, we are discussing MBTs specifically. I can go back further. You say that once sabots became long they needed to be fin stabilized. Correct.

But why did SABOTs get long? When did SABOTs really pick up, after they got long or before they that? Were SABOTs as popular or were HEAT and HESH also accepted anti-tank measures before long-rod SABOT?

In fact the development of smooth bores are intricately linked with development of AFSPDS with T 62.

Artillery guns, have and will retain rifling.

So yes, in the given context, once SABOTs were discovered, that is to say in the long form "once the long rod Armor Piercing Fin Stablized Discarding SABOT became the primary weapon of choice for anti tank purposes the concept of rifling became meaningless."

But I thought all this must be already obvious no? Shorthand saying that tanks guns stopped needing rifling as a meaningful measure after sabots were discussed clearly does not refer to 18th century wooden sabots right?

[Anujan]

Sanku,

I dont want to get into round and round discussions with you. My point is, in your haste to reply, you say very vague things.

When did SABOTs really pick up, after they got long or before they that?

Penetrators got long, Sabots didnt. Sabot is a discardable shroud over the penetrator to hold a sub-caliber round inside the barrel. You might again come back to me and say that you meant the penetrator all along and it is crystal clear from the context.

I on the other hand see it as haste from someone one who is more inclined to post rather than to think.


1. HESH was the primary tank-based anti-tank and demolition weapon till they invented spall liners. You needed HEAT and APFSDS rounds once it was clear that a simple spall liner could defeat HESH in tanks.

2. HEAT is not effective when fired from rifled barrels unless you add slip rings. This is because the HEAT jets get dispersed due to spin. HEAT has to be stabilized somehow. This can be done by making them long, making them sub-caliber and adding fins and a Sabot. But that reduces effectiveness of HEAT because the penetration is proportional to the diameter of the HEAT metal liner. (That is why you have the bulbous head in hand-held anti-tank rounds). You can make HEAT bulbous and stick out of the front of the tank somehow and fire it, but for enough range, it should be rocket propelled rather than an explosive cartridge propelled. Which suits hand-held anti-tank weapons but not tanks.

3. If you are going to make sub-caliber rounds anyway, might as well rely on KE penetrators rather than chemical effects. That is how APFSDS was invented. But it turns out APFSDS can be fired effectively from rifled barrels as well. If you think about it, AP rounds were the first anti-tank rounds! The very first anti-tank weapon was something you would call an anti-material rifle with armor piercing steel core bullet!! So I would argue AP rounds existed as long as rifles and tanks existed. The way of stabilization changed over time due to AP rounds getting longer. That is all.

Here is world's first anti-tank weapon:



A Mauser 1918 T-Gewehr. With rifled barrel firing AP rounds with steel core bullets. Not fin-stabilized, No sabot, no smoothbore. Ofcourse it wouldnt work these days, if you dont make the bullet much longer and impart a higher kinetic energy. Which means it should be fin-stabilized and sub-caliber fired from bigger gun. That doesnt mean rifling is bad, it simply means *rifling is not needed if this is the only bullet you want to fire*


Now all your questions are answered without any deep insight as to why smoothbores are more effective. Also leading questions without providing an explanation just gives an impression of scholarship where there is none.

[Sanku]

Anjuan, over last many years, I have talked about all these points anyway. We are currently in the 300000 cycle of rehashing rifling, sabots, evolution of rounds and such like.

So yes, forgive me for the haste, I have been over this many times, and will probably have to be over this 300000 times more, till the smooth bore fitted Arjun is finally deployed.

You may not know, but I was probably the first on the forum to predict that Arjun will move to smooth-bores, and why. And this was much (2 years?) before the news came out.

So yes, important to understand the context. (Also when the rounds become long, so do the SABOTs)

I have one more advice for you in turn, I see some one inclined to come in and preach without trying to understand the context or the discussion and take sides -- bad idea.

[Anujan]

Thank you for your advice, How are you so sure that I havent been reading this thread? Or is one qualified to post if only one has posted before? (which is quite self-contradictory)

My point is, Arjun might very well become smoothbore, even share a barrel with the T90, not because smoothbores are inherently superior, but because we bought a boatload of tanks which have smoothbores. My other point is, Arjun got a rifled barrel because it was in the GSQR and the army wanted it.

Now, whether IA is willing to give up HESH rounds and instead enjoy advantages of commonality is their choice. Nothing in the news every indicated that Arjun's gun was defective or Russians were brilliant in going for smoothbore or HESH was outdated. The reality is that we are stuck with thousands of tanks with smoothbores and that is the direction we probably have to go.

I wish you accepted this reality, than making arguments based on premises centered on quality and cutting edge or innovativeness of the Russians. That line of argument is pure bogus.

[ramana]

If they want to go smooth bore on Arjun will the claiber match the existing inventory for commonallity or will it be uniquely different?

[Sanku]

How are you so sure that I havent been reading this thread?

It appeared from your statements, if I was wrong, well then its more fun, to discuss.

Lets take one point at a time

My point is, Arjun might very well become smoothbore, even share a barrel with the T90, not because smoothbores are inherently superior, but because we bought a boatload of tanks which have smoothbores.

That argument is possibly valid (not really valid but wont go into it now) IFF the T 90 and Arjun shared the guns.

Now since we have 120 mm on Arjun and 125 mm on T 90. How does the choice of moving Arjun to 120 mm smooth bore really depend on buying boatloads of 125? Where is the commonality?

(the reason why its not valid is because others have moved from rifled to smoothbore when they did not have smooth bores in service)

My other point is, Arjun got a rifled barrel because it was in the GSQR and the army wanted it.

Of course, but then GSQRs were primarily written in 70s, by which the clear advantages of smooth bores were not fully understood all over the world. Also the GSQRs were closely on lines of "previous and old" experience with British tanks which were rifled. (added later --> ok before you jump on me again, the tanks were not rifled, their gun barrels were)

As time changed, so did the aware ness that smooth bores are most optimal for MBTs (in the current phase 70s-20XX) -- things may evolve again.

[Sanku]

If they want to go smooth bore on Arjun will the claiber match the existing inventory for commonallity or will it be uniquely different?

The reports say 120 mm smooth bore, so not common with T 90.

[KrishG]

At the DEFEXPO, Tata Motors displayed scaled models of its concept Futuristic Infantry Combat Vehicle (FICV) (Tracked & Wheeled), including the turret. In addition, the proposed layout of the production facility was also displayed. Tata Motors is one of the four Indian companies, which has been issued the Expression of Interest (EoI) by the Indian Army, for the FICV - a 'Make Indian' project. Tata Motors has accordingly responded to the EoI based on indigenous design and development in association with key technology partners and submitted their response in October 2010.

[ramana]

Sanku and Anujan while you are arguing about "rifling of barrels", the politicians-arms merchants are rifling the military procurements.

[nachiket]

The Arjun MkII isn't getting a new gun. In fact I cannot remember any news about the Arjun getting a 120mm smoothbore gun at all. The only smoothbore talk we have heard about is on the FMBT which is not even a paper tank yet. The only person who seems confident that the Arjun will get a 120mm smoothbore gun is Sanku. I'll appreciate it if he can point us to a news item stating the same.

[Anujan]

Sanku and Anujan while you are arguing about "rifling of barrels", the politicians-arms merchants are rifling the military procurements.

ramana, I agree.

I didnt want to make wild accusations, but what I had in mind was this. The FMBT probably looks suspiciously like a combination of some unachievable project (50 ton tank with 5000 mm armor that can go 200KMPH with 1 liter of water) and some project that the Russians dont have funding for, and want to pile on the cost on some gullible and frightened partner. (I dont want to go on a tangent into discussing Russia's support in UNSC or Nuke reactors or ATV). The Mig21 was bought out of fright, the T90 also bought out of fright. Look at the longevity of those products and the key turn our defense industry and politics took because of those decisions!!

This would make it easy for IA to come back later and say "We dont have a domestic product, but hey!! Look here!! There is a foreign product (which exists only on paper) which perfectly fits our needs!!"

But DRDO says "Oh okay! we will take elements of FMBT and slap it on the Arjun and make a model for you".

As far as I am concerned, at a base level, I dont care if IA wants a IFR probe attached to the Arjun, as long as they make Indian and buy Indian.

[ramana]

For that to happen as long as Congraze is there, OFB will have to open a an off-shore banking operation/holding company to channel kickbacks and then they might buy local!

[chackojoseph]

The Arjun MkII isn't getting a new gun. In fact I cannot remember any news about the Arjun getting a 120mm smoothbore gun at all. The only smoothbore talk we have heard about is on the FMBT which is not even a paper tank yet. The only person who seems confident that the Arjun will get a 120mm smoothbore gun is Sanku. I'll appreciate it if he can point us to a news item stating the same.

You are right. There is no army requirement. Arjun Gun has proven itself and it can file three types ammo + missile.

[Yagnasri]

you are correct sir. The Gun of Arjun purhaps one of the best defence items made in India, if not the best. As for as rifled gun or soombore - What we have has better range/accuracy and can do the job very very well. No one in our possible adversories, be it ChiPanda and PakiS**t has or going to have in forseeable future, anything which this gun can not handle. So why this talk of soombore? May be we need to import it with some mitai dabba.

By the way Tata IFV looks good.

[vina]

3) The advantages of a smooth bore gun are well understood, now that Indian Mil-Ind complex has necessary know-how, they are shifting to smooth bore for Arjun.

. This take the cake.

Sanku Maharaj Ji has been maintaining until now that the minuses against rifling is that they are more difficult to make and more expensive to produce and maintain! Now how is that that the Indian "Mil-Ind" complex had the necessary know how to produce a more "complex barrel" than the simpler and cheaper smooth bore and went ahead to produce it, but are now shifting to smooth bore because, they now have "know how" ..indeed how, by dumbing down themselves? . Another imagined and lets say inspired fiction writing by the Maharaj!

Ah.. Advantages of smooth bore are "well understood" indeed. From times that cannons were created (go take a look at the old cannons in museums around the country), they were smooth bore for a few hundred years ! Rifling came in much later and became prevalent because of it's advantages.

Now Maharaj goes "back to the future" to "understand advantages" of a smooth bore , as if folks didn't know of it all this while!

HEAT is not effective when fired from rifled barrels unless you add slip rings. This is because the HEAT jets get dispersed due to spin. HEAT has to be stabilized somehow. This can be done by making them long, making them sub-caliber and adding fins and a Sabot. But that reduces effectiveness of HEAT because the penetration is proportional to the diameter of the HEAT metal liner. (That is why you have the bulbous head in hand-held anti-tank rounds). You can make HEAT bulbous and stick out of the front of the tank somehow and fire it, but for enough range, it should be rocket propelled rather than an explosive cartridge propelled. Which suits hand-held anti-tank weapons but not tanks.

I had posted on precisely this in the earlier armor threads on why the HEAT from smooth bores suck and suck hard. Heat works best with a big bulbous diameter. The best you can have is the full diameter of the caliber. The French AMX-35 fielded exactly such a round, the Obus-G (google for it), a full bore HEAT round that had the slip rings to prevent it from spinning and was the Main Round and primary anti tank weapon, until the LeClerc was fielded (with a smooth bore I should add, primarily for Nato Ammo compatibility reasons, though just like the L7 and the AMX-35 gun, the LeClerc could "theoretically" fire Nato, but in practice insisted on French only). That must have been the ultimate tank fired HEAT round until now I think.

d. The reality is that we are stuck with thousands of tanks with smoothbores and that is the direction we probably have to go.

I am not sure of that though. The problem with that is if at all you have to "standardize" on a smooth bore, it has to be the Russian 125mm on the T-72/90 with all the inherent problems of limited sabot lengths (because of autoloader size restrictions), no unitary ammo (charge and shells are separate), it has autoloader , a tinder box if hit etc.. etc. The smooth bore on which it will make "sense to standardize", given the logic of installed base, is simply obsolete and has ZERO potential going forward.

From all indications, the next Russian tanks might well have a 125mm, but will have a bustle mounted loader for new long sabot rounds and newer ammo which simply cant be backward compatible with existing T series! So that is a dead end .

It does not make sense to put the T 72/90 gun, carousel loader and death trap tinder box ammo storage on the Arjun or future tanks.

And if you are going to replace the autoloader and turrent on the T series, it is practically a new tank. You might as well go for the Arjuns and if indeed, there is a case to keep the T series chassis and still upgrade the turrent and ammo, why go to the Russians at all, when you have a perfectly and highly competent solution that you have developed for the Arjun..

You may not know, but I was probably the first on the forum to predict that Arjun will move to smooth-bores, and why. And this was much (2 years?) before the news came out

. What news , and where ? The bins along with the Mayan prophesy and Elvis Born Again and Coming of the Messiah kind of predictions!

Of course, but then GSQRs were primarily written in 70s, by which the clear advantages of smooth bores were not fully understood all over the world. Also the GSQRs were closely on lines of "previous and old" experience with British tanks which were rifled. (added later --> ok before you jump on me again, the tanks were not rifled, their gun barrels were)

. Great fiction writing. The Arjun project itself was probably not conceived in the 70s in the current form. The GSQR itself went through multiple changes, including a biggie of change in gun spec from 105mm to 120mm , and no change in reqmt to smooth bore! It is funny, that the IA/DRDO knew of the trend to 120mm, but not towards smoothbore and this couldn't be anything but a considered decision to retain the rifled gun. As for experience with the "previous and old" and hence not aware of new, I am pretty sure that the IA and the Defense R&D folks in the 70s knew perfectly well about the trends. After all,they did attend conferences, exercises and subscribe to journals and knew far better than the pre internet and Google warrior Maharaj days , who I suspect wasn't even born in the 70s or was at best a toddler back then.

[RoyG]

Sok vina, it'll take sometime for sankuji to come around. Arjun beat t-90 in trials and sports a lethal gun. what must be done now is to free up defence R&D and production to private players so we further build on quantity and quality. TATA FICV looks promising along with towed and SP howitzer projects from Bharat Forge, TATA, and L&T.

[Sanku]

I am sorry ignorance is not anything to be proud of, you guys can go and take a look at this thread (which has a search function) or google.

If you guys still cant catch up on news about Arjun getting the smooth bore, let me know, I will provide the information.

[Sanku]

Sanku and Anujan while you are arguing about "rifling of barrels", the politicians-arms merchants are rifling the military procurements.

There is no hope what so ever for the country as long as the current dispensation is in power. (and changing a minister does not change the dispensation)

In that case at least we can discuss science and engineering to cheer ourselves up.

[Sanku]

The Arjun MkII isn't getting a new gun. In fact I cannot remember any news about the Arjun getting a 120mm smoothbore gun at all. The only smoothbore talk we have heard about is on the FMBT which is not even a paper tank yet. The only person who seems confident that the Arjun will get a 120mm smoothbore gun is Sanku. I'll appreciate it if he can point us to a news item stating the same.

Nachiket, FMBT will have to be Arjun++. There are no other designs that exist.

(This is of course modulo the discussion on corruption etc)

[Eric Leiderman]

Read a report by an Isreaili tank commander, about 2 years back, in which he talks of the Arjun gun, To paraphrase what he says fm memory.
It looks like the indians hit gold with the gun its penetrating power is phenominal ,It went clean through 2 + tanks, he has not seen a gun as good as this one yet.
He thought it was a fluke that we managed to produce the gun(I do not) I would think the rifiling has something to do with the penetrative properties of the shell. The blog spot of this guy was on BR, I cannot find the link.