Is Rifled gun on Arjun tank a mistake?

[Yaduveer]

A tank has 3 major components-Armament,Mobility and Protection.Kanchan composite armour gives requisite protection for Arjun tank as expected from 3rd generation Tanks. Hydropneumatic suspension and German MTU engine cover sufficient performance in Mobility department.Armament is the major unsatisfied area as expected from a 55 ton weighted tank. Choice of 120 mm Rifled barrel was major drawback in Arjun project. Excellent choice would be 120mm smoothbore barrel for following reasons.

1. Modern day tanks used for mainly anti-tank armour piercing round like HEAT(Highly explosive anti tank) round or armour-piercing fin-stabilized discarding sabot (APFSDS). Due to availability of fins and nature of thin and long armour piercing round do not need 'rifling' to spin the round for greater accuracy and range.

2. Re-rifling of barrel is needed after discharging (firing) about 400 rounds.In a war like situation , rifling of bore can add some logistic problems.

3.Since Kinetic energy = mass X speed X speed ,smoothbore can impart greater speed same mass as energy is not wasted in spinning of round.Although 125 mm gun do not withstand to provide same level of speed as in 120mm. Hense 120 mm smoothbore is better choice.

4. Missile can launched from smoothbore more effectively .You don't need to spin the missile although bypass procedure has been made in rifled guns.

5. 120mm smoothbore is standard gun hence has wide variety of ammunition.More over All major tanks are moving or moved for smoothbore Like M1 Abraham,Leopard and K2 Black Panther.

Advantage of rifled gun is of firing HESH(High explosive squash head) which is more effective against concrete. This is one small advantage compare to many disadvantages.

Neither Arjun mk 1 nor Arjun Mk2 has incorporated this measure. I hope guns like l44 or l55 will be installed in Arjun.(L/55 gun is installed into Challenger 2 and Black panther ) Even American Abraham tank uses licensed version of German L/44 gun.

 

[LiberalAtheist]

will Arjun MK2 feature smoothbore gun? i think ARDE should begin R&D on a smoothbore gun

 

[Yaduveer]

will Arjun MK2 feature smoothbore gun? i think ARDE should begin R&D on a smoothbore gun

As far i know , DRDO has not incorporated smoothbore into Arjun Mk2.
120 mm Rifled gun will create logistic problems as India has to make all round in-house.Also India can not benefited with emerging technologies like guided or programmable HEAT round etc.

 

[Omega007]

Let me try to answer your doubt.
The rifled gun is indeed problematic not due to lack of power but more due to its shorter longevity as the grooves wear out very rapidly and has to be changed more frequently than smooth barrel guns.
But rifling doesn't impact the performance of FSAPDS rounds (much) if you can properly design the sabot.Actually,FSAPDS rounds don't spin (or not let to spin) even when fired from rifled guns.Why??Because we use bearings into the sabots,so when the round is fired from the gun the sabot around the penetrator rod start to spin but the rod itself doesn't spin and remains as linear as if would have been fired from a smooth bore gun.

Now,coming to ARDE L/52 rifled gun.According to the official website of ARDE,this gun can withstand maximum chamber pressure of 840 mpa or 8400 Bar which is beyond the capability of even the all powerful Rheinmetall L/55 which can withstand upto 7500 bar.And the present ARDE unitary longrod FSAPDS rounds are fired at chamber pressure of 620 mpa as per official website which is much higher than the latest Rheinmetall DM 63 (500 MPa).
Now,the ARDE MkI FSAPDS rounds are fitted with a 780mm long 8 kg penetrator which is fired at 1700 meter/sec according to the OFB site.So you can see that the Arjun's gun has got almost the same initial mussel velocity of Rheinmetall L/55 (1750 m/sec).So it's not true that ARDE L/52 can't generate enough power.
Now coming to HEAT part-a CL 20 based HEAT round for Arjun is already under development.
Now coming to use of international ammo part-well,standard NATO FSAPDS rounds can't be directly fired from ARDE L/52 but the penetrators can be imported and then fit them with indigenous sabots and charges and you can have what you wanted.But current penetrators are well upto the job and a new self sharpening round is now under testing (not published in media yet but you can count on my words as my dad works in PXE,Balashore).

 

[ganimi kawa]

Let me try to answer your doubt.
The rifled gun is indeed problematic not due to lack of power but more due to its shorter longevity as the grooves wear out very rapidly and has to be changed more frequently than smooth barrel guns.
But rifling doesn't impact the performance of FSAPDS rounds (much) if you can properly design the sabot.Actually,FSAPDS rounds don't spin (or not let to spin) even when fired from rifled guns.Why??Because we use bearings into the sabots,so when the round is fired from the gun the sabot around the penetrator rod start to spin but the rod itself doesn't spin and remains as linear as if would have been fired from a smooth bore gun.

Now,coming to ARDE L/52 rifled gun.According to the official website of ARDE,this gun can withstand maximum chamber pressure of 840 mpa or 8400 Bar which is beyond the capability of even the all powerful Rheinmetall L/55 which can withstand upto 7500 bar.And the present ARDE unitary longrod FSAPDS rounds are fired at chamber pressure of 620 mpa as per official website which is much higher than the latest Rheinmetall DM 63 (500 MPa).
Now,the ARDE MkI FSAPDS rounds are fitted with a 780mm long 8 kg penetrator which is fired at 1700 meter/sec according to the OFB site.So you can see that the Arjun's gun has got almost the same initial mussel velocity of Rheinmetall L/55 (1750 m/sec).So it's not true that ARDE L/52 can't generate enough power.
Now coming to HEAT part-a CL 20 based HEAT round for Arjun is already under development.
Now coming to use of international ammo part-well,standard NATO FSAPDS rounds can't be directly fired from ARDE L/52 but the penetrators can be imported and then fit them with indigenous sabots and charges and you can have what you wanted.But current penetrators are well upto the job and a new self sharpening round is now under testing (not published in media yet but you can count on my words as my dad works in PXE,Balashore).

Posts like these increase the level of discussion. Nice job mate!

P.S. you may want to delete the last two lines from your post. Let the DRDO disclose this when they feel the time is right.

 

[ptltejas]

Let me try to answer your doubt.
The rifled gun is indeed problematic not due to lack of power but more due to its shorter longevity as the grooves wear out very rapidly and has to be changed more frequently than smooth barrel guns.
But rifling doesn't impact the performance of FSAPDS rounds (much) if you can properly design the sabot.Actually,FSAPDS rounds don't spin (or not let to spin) even when fired from rifled guns.Why??Because we use bearings into the sabots,so when the round is fired from the gun the sabot around the penetrator rod start to spin but the rod itself doesn't spin and remains as linear as if would have been fired from a smooth bore gun.

Now,coming to ARDE L/52 rifled gun.According to the official website of ARDE,this gun can withstand maximum chamber pressure of 840 mpa or 8400 Bar which is beyond the capability of even the all powerful Rheinmetall L/55 which can withstand upto 7500 bar.And the present ARDE unitary longrod FSAPDS rounds are fired at chamber pressure of 620 mpa as per official website which is much higher than the latest Rheinmetall DM 63 (500 MPa).
Now,the ARDE MkI FSAPDS rounds are fitted with a 780mm long 8 kg penetrator which is fired at 1700 meter/sec according to the OFB site.So you can see that the Arjun's gun has got almost the same initial mussel velocity of Rheinmetall L/55 (1750 m/sec).So it's not true that ARDE L/52 can't generate enough power.
Now coming to HEAT part-a CL 20 based HEAT round for Arjun is already under development.
Now coming to use of international ammo part-well,standard NATO FSAPDS rounds can't be directly fired from ARDE L/52 but the penetrators can be imported and then fit them with indigenous sabots and charges and you can have what you wanted.But current penetrators are well upto the job and a new self sharpening round is now under testing (not published in media yet but you can count on my words as my dad works in PXE,Balashore).

Great to know sir. Can we go for both type smooth bore as well rifled.

 

[Yaduveer]

Let me try to answer your doubt.
The rifled gun is indeed problematic not due to lack of power but more due to its shorter longevity as the grooves wear out very rapidly and has to be changed more frequently than smooth barrel guns.
But rifling doesn't impact the performance of FSAPDS rounds (much) if you can properly design the sabot.Actually,FSAPDS rounds don't spin (or not let to spin) even when fired from rifled guns.Why??Because we use bearings into the sabots,so when the round is fired from the gun the sabot around the penetrator rod start to spin but the rod itself doesn't spin and remains as linear as if would have been fired from a smooth bore gun.

Now,coming to ARDE L/52 rifled gun.According to the official website of ARDE,this gun can withstand maximum chamber pressure of 840 mpa or 8400 Bar which is beyond the capability of even the all powerful Rheinmetall L/55 which can withstand upto 7500 bar.And the present ARDE unitary longrod FSAPDS rounds are fired at chamber pressure of 620 mpa as per official website which is much higher than the latest Rheinmetall DM 63 (500 MPa).
Now,the ARDE MkI FSAPDS rounds are fitted with a 780mm long 8 kg penetrator which is fired at 1700 meter/sec according to the OFB site.So you can see that the Arjun's gun has got almost the same initial mussel velocity of Rheinmetall L/55 (1750 m/sec).So it's not true that ARDE L/52 can't generate enough power.
Now coming to HEAT part-a CL 20 based HEAT round for Arjun is already under development.
Now coming to use of international ammo part-well,standard NATO FSAPDS rounds can't be directly fired from ARDE L/52 but the penetrators can be imported and then fit them with indigenous sabots and charges and you can have what you wanted.But current penetrators are well upto the job and a new self sharpening round is now under testing (not published in media yet but you can count on my words as my dad works in PXE,Balashore).

If rifled gun is generating same amount of power that of Smoothbore, then rifled gun must be heavy compare to smoothbore. Can also give me wieght of L 52 ? There is a little correction maximum Muzzle velocity is 1800m/s for L55.

This is root of problem you have to work around every ammo of international standard. But you can not deny the fact that L55 or l44 is superior gun , can you ? Arjun is only tank which uses Rifled gun apart from challenger 2 of which is also moving towards smoothbore.

 

[angeldemon_007]

Looking at the best war-fighting MBT in the world i would say there must be a reason why its the best, why its gun is liked by everyone.

From Engineering point of view of course one might say Leopard 2 is also very good but if we see the actual war statistics, Challenger 2 has proven itself in the last decade.

 

[Yaduveer]

Looking at the best war-fighting MBT in the world i would say there must be a reason why its the best, why its gun is liked by everyone.

From Engineering point of view of course one might say Leopard 2 is also very good but if we see the actual war statistics, Challenger 2 has proven itself in the last decade.

That is my question also , Even Challenger is moving towards incorporating Smoothbore why not Arjun ?

 

[Omega007]

Looking at the best war-fighting MBT in the world i would say there must be a reason why its the best, why its gun is liked by everyone.

From Engineering point of view of course one might say Leopard 2 is also very good but if we see the actual war statistics, Challenger 2 has proven itself in the last decade.

Best in the world!!It's not wise to call a model 'best' just by looking at the technical specification,you have to count many more things like quality of training of crews of both sides,quality of tanks of opponents etc.
By the way,the ROF L30 of Challenger Mk2 is not upto the mark at all.

 

[angeldemon_007]

^^^
Dude Challenger 2 is called best simply because it shown the world over and over again during the wars while Leopard 2 is not been so thoroughly tested other than training exercises. There are few Leopard in Iraq and Afg. but they all came later while Challenger is standing their has proven better than any other tank there till now. What can be a better test for a tank than a war ??

That is my question also , Even Challenger is moving towards incorporating Smoothbore why not Arjun ?

If thats true then for FMBT we should built a smooth bore also then drdo should test both of them and find out which will be better for IA. But firstly, is there a source to confirm what you are saying because Challenger 2 has a very powerful gun.

 

[Omega007]

^^^
Dude Challenger 2 is called best simply because it shown the world over and over again during the wars while Leopard 2 is not been so thoroughly tested other than training exercises. There are few Leopard in Iraq and Afg. but they all came later while Challenger is standing their has proven better than any other tank there till now. What can be a better test for a tank than a war ??


If thats true then for FMBT we should built a smooth bore also then drdo should test both of them and find out which will be better for IA. But firstly, is there a source to confirm what you are saying because Challenger 2 has a very powerful gun.

Not very powerful man.During NATO gunnery exercises,the Challengers were repeatedly out performed by Leopard 2s and Abrams.
Besides,according to Steven Zaloga,the ROF L30 of Challenger 2 can withstand only 6200 bar chamber pressure which comes nowhere near modern 120mm guns.And hence the L30 has much lesser range and penetration value than other guns..

 

[ApparentRaceTraitor]

That is my question also , Even Challenger is moving towards incorporating Smoothbore why not Arjun ?

Possibly the Mk.3 versions? (please correct me if information for this has already been released)

 

[Omega007]

Great to know sir. Can we go for both type smooth bore as well rifled.

Why not??But that won't make any sence as rifled guns give no advantage over smooth barrel guns.Besides,then you have to produce two differet kinds of ammunitions for the same weapon platform which will farther complicate the logistics.So if Army decides to use smoothbore guns of Arjun in future,they should go for it and then there will be no need to retain those rifled guns.

 

[DARKY]

If rifled gun is generating same amount of power that of Smoothbore, then rifled gun must be heavy compare to smoothbore. Can also give me wieght of L 52 ? There is a little correction maximum Muzzle velocity is 1800m/s for L55.

This is root of problem you have to work around every ammo of international standard. But you can not deny the fact that L55 or l44 is superior gun , can you ? Arjun is only tank which uses Rifled gun apart from challenger 2 of which is also moving towards smoothbore.

I don't know why so much fuss about maximum muzzle velocity.
Would like to Remind here that KE penetrators like the D53/63 or M829A3/A4 don't fire at maximum muzzle velocity... rather they are just a little more than half of it in case of American M829A3.