T-72s in Chechnya, From Armour Magazine

Sanjay · Post by **Sanjay** » 12 Nov 2001 22:41

Administrator's comments aside, anyone interested in the Arjun's development should read the Indian Def. Review of April 1993.In it, the following comment was made:The Kanchan armour with its combination of monolithic/ composite armour, should provide adequate protection against the Khaled firing high-velocity APDSFS rounds.

JCage · Post by **JCage** » 12 Nov 2001 22:58

Raj, Meant L/D ..Paul i hazard needs it to plug into Andersens formula... Sanjay,I wouldn't take the range claims too seriously since these are the realistically engageable combat ranges of the Indian army. Yes the FSAPDS round can defeat a triple heavy target at a longer range, but there is little point in DRDO saying so since the army doesn't care. There view is simple - will it defeat frontal armour of T-80 etc. at realistic battle ranges. Answer may well be yes. I agree.The normal battle range extensively quoted is the 2km one by all manufacturers.The news about the pakistani APFSDS imported round not exceeding 460-480mm is also important.It may bring the first current news of what they realistically did obtain from the chinese...and are license producing at POF. The DRDO website(link i gave above) clearly mentoions hypervelocity 120mm ammo and the admirable results obtained. Let me just say this, I'm led to believe that in testing the Arjun's armour, 125mm FSAPDS rounds imported from Russia were fired at it at various ranges. Indeed, Arjun's armour was designed to take this on -the army would not have accepted anything less. The armour was also required to protect against TOW-2. If the army says the armour is OK, at this stage, we have insufficient evidence to the contrary. Very good point.Also speaks volumes about what the Army wanted and DRDO's attempts to satisfy the same.These are the rounds in service with the russians today....and the details(V.Fofanov) APFSDS Muzzle velocity 1700 m/s 3BM32 DU Penetrator (First shown to the west in 1993; est.DOI 1988) Total penetration route: 680mm RHA at 90° at 2000m 3VBM17 (3BM42 Tungsten Alloy Penetrator) (First shown to the west in 1993; est.DOI 1988) 250mm RHA at 60° at 1000m 230mm RHA at 60° at 2000m If the DU round was tested,kanchan is better than anything previously guessestimated.The 3BM42M is a new round-tungsten penetrator with a 20% increase over the 3BM42...supposed to be in service by 1998-99,at least NIMI aimed to produce it by then.If the IA/DRDO did import rounds....it stands to reason that the DU round may well have been tested considering that pakistan (POF) was intending to produce them and is doing so currently.That itself takes kanchan and hence Arjun's protection at above 57 cm KE.The Arjun was always designed to view the Khalid or whatever PRC tank it was derived from as the adversary and to be able to defeat it at all combat ranges. This was the threat seen since 1993.It gets better and better.

If anybody can find the links for V.N. Sharma's Kanchan comments it would be very important. Sharma is not prone to flights of fancy and is very conservative in his comments. If he said that about Kanchan, I'd not want to refute him easilyI did search the Tehelka.com site...unfortunately the specific article seems to be missing.But it was posted on BR quite some time back and i did save the relevant portions. The quotes posted above by me are Exact ones from the article.The remaining was about the General visualising /advocating the use of IIT's etc.The examples quoted by the Gen given above were the only ones relevant to the arjun/kanchan.For what its worth,the article was part of a series called "Tehelka's Debate On National Security".Its existence is confirmed by this link. <a href="http://www.tehelka.com/channels/investi ... R>Again, problem with Arjun's armour was machining the turret armour to get a good ballistic shape against FSAPDS rounds. In 1993, the Indian Defence Review commented that it is one thing for the armour to stand up to all threats in the lab and testing ranges, quite another when it is fitted to the tank. They were arguing for better shaping of turret Right.Appears that Mk2 will have the needful +ERA.ERA at the correct angle and comprehensive/heavy enough will be even better against KE.Kanchan "sloped" as desired will add even more. Also, the Arjun has vastly improved ammunition stowage versus T-72. This was a major priority because the crew of a T-72 burnt to death during an exercise back in 1993. Yeah,Its there at the CAG website.The army's desire to have the QSR's upgraded to include blowoff panels and its acceptance by the DRDO is recorded.Now we know the reason. The inference is that ammo is now stored in a bustle and probably separated from the crew. I can't answer directly the question on the density of the Kanchan armour on the Arjun, but I can say that the Arjun was supposed to weigh in at 45 metric tons and comes in at at least 58 at present. This is apparently entirely due to the Kanchan Wow.The latest/last weight was 61.5T...the army asked for it to be reduced to 58.5.Details in my previous posts(2nd one in this thread). What I will say is that the Indian army has a very clear threat perception and will not accept something that does not work. It has never done so before and I can't see them doing so nowAgreed.The IA despite all its quirks works according to a solid perception. This discussion has brought out the true and positive side of arjun,the IA,DRDO!No country has written so much against its own tank designs as India has about the Arjun. It's a point worth considering.Satyameva Jayate gone astray. :)It may also indirectly alude to the extremely high standards demanded by the end user.Whats more they appear to be getting it.

Regards, nitin

Sanjay · Post by **Sanjay** » 12 Nov 2001 23:02

Hate to say it, but it is a de facto dud.The tank will not and cannot ever be the Main Battle Tank of the Indian army. Too big, too heavy and too expensive.My take is that any def. industry has to take risks. Whatever else, India learned how to make some pretty advanced armour, an anti-tank FSAPDS round and 120 mm rifled gun from scratch. It also learnt how to make a fire control system, thermal imagers and a hydropneumatic suspension.Arjun is for CVRDE an experience and for the army a glimpse into what might be possible.Somebody commented on Arjun's armour remaining the same shape. That's so only for Mk.1. If the armour remains the same for Mk.2, then we can be pretty sure that armour performed well. I think that the Leopard 2A5 may be the future of what the Arjun looks like.As far as ammunition goes, the 105mm FSAPDS round was designed to penetrate frontal armour of T-72. At the time, it was the best tank India had real access to. Back in the late 1980s - up to its Jan 1990 issue - Indian Defence Review used to do periodic state of armour updates. They were an eye opener into armour upgrades.Paul, here's one thing to take into account -for several years the APDSFS ammunition of the Leopard-2 was described as having the ability to penetrate the triple NATO heavy target at 2200+ metres. I suspect the same applies to India's ammunition descriptions !As an aside, the HAPP project at Trichy was set up because imported APDSFS ammunition was somewhat lacking in performance. This was true particularly of the 125mm FSAPDS round imported from Russia.

Sanjay · Post by **Sanjay** » 12 Nov 2001 23:10

Nitin, You know I'd forgotten the real importance of the T-90 - new Russian ammunition !I wonder if production will be established in years to come ? Especially since, when some DRDO projects were cancelled, it is possible that the 125mm FSAPDS round is apparently going to be taken out of production.A lot to learn.If I might ask a favour, please e-mail me the comments V.N Sharma made - the relevant portions you saved. e-mail: [email protected]Thanks

JCage · Post by **JCage** » 12 Nov 2001 23:14

tow2 Details:http://www.royhaaland.net/norway/tow/Type: Hughes BGM-71 TOW (Tube launched Optically-tracked Wire guided anti-tank missile Dimensions: length 1.174m for basic model, 1.555 for Improved TOW with probe, and 1.714m for TOW2 with probe, diameter 15.2cm, span 34.3cm Launch weight: 22.5kg for basic model, 25.7kg for Improved TOW, and 28.1kg for TOW2 Propulsion: two-stage solid-propellant rocket Performance: range 65-3000m for pre- 1976 models, and 65-3750m for post- 1976 models Warhead: 3.9kg shaped-charge HE for basic and Improved TOW models, and 5.9kg shaped-charge HE for TOW 2 model Armour penetration: 600mm for basic model, 700mm for Improved TOW, and 800mm or more for TOW2 If the Kanchan matched up against this(the TOW2)..it means protection against minimum 800mm CE(HEAT). :)Taking the website at face value. <A HREF="http://www.fas.org/man/dod-101/sys/land/tow.htm" TARGET=_blank>http://www.fas.org/man/dod-101/sys/land/tow.htm</A> The above also confirms the same.Greater than 700mm for the latre variants.The TOW2 is in service with the pukes.Makes ample sense to have kanchan withstand it.Regards, nitin

JCage · Post by **JCage** » 12 Nov 2001 23:52

Guys., Before "realism" based on CAG reports etal seeps in,lets remember that the last CAG report mentioned is of 1997 vintage-4 years back! And if one goes thru the archived reports..each successive "failure" at trials actually includes at least 1 success constituting yet another parameter achieved.That parameter not being mentioned as "yet to be achieved" after the next series of trials.The statesman article is the latest@2000 and deserves respect. Sanjay, Not a single report till now has mentioned anything about the T90 ammo-its apparently hush-hush. My take is that it will definitely replacet the one in current production,if its better, or at least be produced side by side if the russians give Transfer Of Tech.Did you check the stratmag link on the T72 upgrade?If my memory serves me right,it mentions that even the 125MM main gun-2A46M will get upgraded in the ajeya upgrade!The T90 gun is a much improved 2A46M-2 which has benefitted from new manufacturing tech imported by the russians.I'll locate the VN Sharma article excerpts-its there-and get it to you in a days time.(cluttered HDD

).regards, nitin

Paul_L · Post by **Paul_L** » 13 Nov 2001 00:54

<BLOCKQUOTE>quote:<HR>Originally posted by nitin: Raj, Paul,That L/D ratio is from this link.Muzzle velocity given in Raj's post. <A HREF="http://www.drdo.org/products/fsapds.htm" TARGET=_blank>http://www.drdo.org/products/fsapds.htm</A> It has more on the indian 125mm APFSDS.BTW, How does the pic of the IA T72 appear to you?Will it degrade KE attack in any significant manner? Regards, nitin<HR></BLOCKQUOTE>ERA looks like straight Kontakt which should offer 2cm @ angle so the glacis and turret should offer ~ 4-6cm KE resistance and ~ 400mm HEAT resistance. The cal comes from studies of numerous Int.J.Impact Engng articals to many to list ...if any ones interested in more detail on this and Andersons formulas I have some of the papers on PDF files that I can email.{some new ones for you to Nitin}.<[email protected]>What I need to estimate APFSDS through Andersons is MV ; V drop; projectile and penetrator ;length projectile & diameter and material [ DU, WHA, Steel or Sheathed ].For those who asked the triple heavy target penetration at 4-6km comes from JANES ammo hand book 94/95. And the importance of penetration at longer range means the penetration at shorter range is much higher.The original german 120mm APFSDS was the DM-13 that can only penetrate 400mm at muzzle so penetration of Triple target at 2-3km sounds close. But the DM-33 can penetrate 550mm @ 2km and and the triple heavy target should be 5-6kms range.

Sanjay · Post by **Sanjay** » 13 Nov 2001 02:51

Paul, point well taken. Just to say though, I doubt that DRDO will ever claim 4-6km if only because the questions regarding Israeli help will come up. With HESH, they never say they can engage at 8000 metres except for that slip regarding upgrading T-55s.DRDO's claims on the 125mm FSAPDS are also governed by the fact that the gun of the T-72 has very poor sighting facilities beyond 3500m. It's pretty bad beyond 2000 metres. That's why India wants a completely new FCS rather than just getting thermal imaging sights. So many factors !Likewise, the 105mm gun's sighting systems on both the Vijayanta and T-55 are not great beyond 3500m - indeed, with many Vijayantas, they're still using the 12.7mm ranging machine gun as a basic aiming system. That's only got a range of 1800m.What DRDO says when asked is the following:'It defeats all NATO targets at ranges of 2500m and beyond'. When pushed they say:'It destroys tanks at all possible battle ranges'.You know what the most ridiculous thing is ?The DRDO is claiming the same penetration for the 105mm and 125mm FSAPDS. How:"The technologies associated with the FSAPDS ammunition have been fully developed by taking ab initio R&D activities in DRDO. The technology has been extended to enhance fire power of tank guns in calibres of 105 mm, 120 mm and 125 mm. FSAPDS is a sub-calibre projectile (penetrator) successfully designed to meet the ballistic requirement in the gun and at the target. The high length-to-diameter (L/D) ratio makes this penetrator capable of defeating all triple heavy targets at a range of 2500 m."They are not distinguishing between calibre performance ! <A HREF="http://www.drdo.org//pub/feb98/armament.htm" TARGET=_blank>http://www.drdo.org//pub/feb98/armament.htm</A> The 105mm FSAPDS round is the one that entered production first. However, I believe strongly that a UK FSAPDS round in 105mm was imported and built at the Ordnance factories.Read this: "This ammunition is of UK design and is high technical ammunition among the 105-mm version." <A HREF="http://www.weaponsindia.com/cartgfsapds.htm" TARGET=_blank>http://www.weaponsindia.com/cartgfsapds.htm</A> Now, here's something interesting:There are very few areas in the India Pakistan battlefield where tanks can be engaged beyond 2100 metres.Nitin, Pakistan only operates TOW-2.Of, course! Why didn't we think of it before ? They need the T-72 to also fire missiles, so they need a new gun.Nitin, what is the stratmag link ?Here is something on Indian ERA:"For providing adequate protection to the battletanks against attack by HESH, kinetic energy (KE) and shaped charge warheads, Explosive Reactive Armour (ERA) has been successfully developed which has now been accepted by the Army. The technologies involved in making the panels have been successfully transferred to the Ordnance Factories" <A HREF="http://www.drdo.org//pub/feb98/armament.htm" TARGET=_blank>http://www.drdo.org//pub/feb98/armament.htm</A>

Paul_L · Post by **Paul_L** » 13 Nov 2001 04:50

Indian 125mm APFSDS <A HREF="http://www.drdo.org/products/fsapds.htm" TARGET=_blank>http://www.drdo.org/products/fsapds.htm</A> Indigenous development of the 125mm APFSDS for the Indian T-72 and T-90 tanks . The projectile is reported to be have a L/D of 15:1 and a MV of ~ 1550 m/s. But examination of the pics suggest the overall projectile L/d is about 18-19:1. This suggests the penetrator is 15:1 L/d while the visible projectile diameter 0.23 of sabot diameter for a projectile diameter of 29-30mm , which makes the penetrator length ~ 45cm and the projectile ~ 56cm …similar to the BM-42 and Polish Pronit. Given a MV of 1550m/s the projectile must be very heavy since similar projectiles designed in Poland and Russian get 1650-1700m/s for a 7.05kg projectile & Sabot, but the reports suggest only 7.08kg so perhaps Indian propellant tech is not so advanced. Going on the 30mm diameter and a notional projectile mass of 4.35kg [Pronit] the penetrator is unlikely to be more than 4000g for a volume of 228 cc assuming a normal density 17.5 g/cc tungsten alloy for a penetrator length of only 32cm [228÷ 7.06 ] or 11:1 L/d .Given a 45cm 15:1 L/d penetrator , the only explanation that fits is that the penetrator is sheathed in some way which may explain why they refer to a ‘ soft tungsten core’ . The volume should work out to ~ 318cc which makes the bulk density ~ 12.6g/cc …this corresponds to sheathing of 15% and a penetration of 90% of the straight tungsten alloy penetration value . Since a straight cylinder is suggested the conversion from Semi infinite to finite target is + 1.3d @ 0° & +2.6d @ 60° or + 3.9 & 7.8cm and the scaling should be 30/6.4 x 5% = x 1.23. The BM-32 & BM-42 suffers a V-drop of 120m/s/km so I will assume an improvement to a Vdrop of 110 m/s/km. The Andersons inputs should be 1.044V – 0.194 x [In of L/d] – 0.212 . thus the formula works out to 1.044 V [velocity in km/s] – 0.737 [L/d] x 0.9 [ sheathing] x 1.23 [scaling] + 3.9/7.8 . The 60° penetration estimate is an LOS penetration and the estimated penetration at range looks like … <PRE> Muzzle 1550m/s [ 1.55 x 1.044 – 0.737] x 0.9 x 1.23 = 0.975 x 45cm = 43.9 + 3.9/7.8 = 48± 7cm @ 0° & 52±7cm @ 60° 1000m 1430m/s [ 1.43 x 1.044 – 0.737] x 0.9 x 1.23 = 0.837 x 45cm = 37.6 + 3.9/7.8 = 41±7cm @ 0° & 45±7cm @ 60° 2000m 1310m/s [ 1.31 x 1.044 – 0.737] x 0.9 x 1.23 = 0.7 x 45cm = 31.4 + 3.9/7.8 = = 35±6cm @ 0° & 39±6cm @ 60° 2500m 1275m/s [ 1.275 x 1.044 – 0.737] x 0.9 x 1.23 = 0.636 x 45cm = 29.5 + 3.9/7.8 = 33±5cm @ 0° & 37±5cm @ 60° 3000m 1190m/s [ 1.19 x 1.044 – 0.737] x 0.9 x 1.23 = 0.56 x 45cm = 25.2 + 3.9/7.8 = 29±4cm @ 0° & 33±4cm @ 60° 4000m 1070m/s [ 1.07 x 1.044 – 0.737] x 0.9 x 1.23 = 0.42 x 45cm = 18.9+ 3.9/7.8 = = 23±3cm @ 0° & 27±4cm @ 60° </PRE> The ballistic reports on this round suggest Triple heavy NATO target penetrated at > 2.5 kms which suggest some where between 2.5 to 3.0km range. The Triple heavy NATO target is a three layered array with 10mm semi hard steel plate with 33cm airgap, followed by a 25mm mild steel plate with a 33cm airgap followed by an 80mm RHA armored plate , all set back at 65°. The solid LOS thickness works out to ~275mm but given the effectiveness of the differing plates this should be equal to ~ 26cm RHA. However this ignores the effects of shattering and yaw on projectiles that have to penetrate multiple plates , which boost the effective resistance of this type of array back up to about 36cm. Now this is based on a good deal of speculation so more details are needed to narrow down the actual penetration potential of this round. This looks better than the Steel 125mm BM-15 and similar to the Sheathed 125mm BM-22 in penetration. By comparison this round is close to the penetration of the British L23 120 APFSDS at short range and the British 105mm H-6/62 APFSDS at long range, its also only marginally better than the MECAR M-1000 APFSDS-T -that’s been in production for the 100mm gun on Pakistan’s T-59 since the mid 90s.

Sanjay · Post by **Sanjay** » 13 Nov 2001 06:18

Paul, thanks a lot for putting this in perspective. When was that 105mm developed ?Now here's a poser for you, if the Indian 125mm round can penetrate a NATO triple heavy target at 3500m, what more can you say compared to the L23 120mm round ?I'm not sure, but there is a real chance of the 125mm round defeating NATO triple heavy at 3500m - this is because it's effective lethal range is now given as 3.5km. Where ? Well, this was in the latest catalogue by the Directorate of Standardization.An interesting twist is put on everything with this line in the Tribune Nov.20, 1999:"Sources say that the indigenous FSAPDS round is superior to the existing service ammunition in accuracy and lethality. It is said to be capable of defeating all known NATO armour at a range of 2,500 meters."Again, I should stress that the same 'defeat NATO triple target at 2500m and beyond' is used for the 105mm FSAPDS round as well - this round ceased production a few years back. The 105mm FSAPDS round was developed in 1982-84. Also, the penetrator is very heavy. I learned this back in 1995/6. When I asked the weight/ mass, I was told to back off. So go figure. Finally, it appears that future Indian FSAPDS may be license made foreign designs - Indian Express 18 May 2001: "Those which have been or will be closed include the FSAPDS (steel core) ammunition" Expect T-90 and re-gunned T-72 carry latest Russian rounds. I also expect tech transfer to OFB.Paul, as an interesting aside, Pakistan has replaced the 100mm guns on the T-59s with 105mm guns. At least on most of them.

JCage · Post by **JCage** » 13 Nov 2001 15:58

Hi sanjay, I knew the pakistanis had the TOW2,i just referred to them as pukes.

Damn,do i really hate this...i lost my entire post....darn ubb. Here i go again. #1.Ref:To the T72 needing an upgraded main gun for ATGM's ...i think a new FCS+ laser guidance system would itself do the trick.The main gun if upgraded gives us better reliablity and better performance(can withstand higher muzzle velocity etc).The 2A46M-2 has a new chromium liner for the barrel and it is also easier to field change the barrel .Hence,upgrading the main gun would probably be for better conventional prerformance rather than ATGM's per se..Lets see.the May-june 1998 issue of Armour magazine has this to say about the IA t72 and the ATGM issue...and other things.1.The limitations of the soviet design became apparent in 1986 itself2.1/3 of the vijayas will be completely modernized and the remaining partially retrofitted.,depending on their condition and serviceability4.Fully upgraded ones will receive new fcs,landnav systems and ERA which is claimed to reduce ATGM effectiveness by 80% and 840hp diesel engines.5.A select group of rhino's will receive the ssb119m svir missile In 1993,the svir cost of 45,000$ made the cost of 30 such missiles equal to the cost of a single t72 tank(The first tanks rolled off indian assembly lines in 87 at 835,000$ apiece).6.While the russians issue 4 per tank,the indians apparently plan to issue 6!!Now cut to the present,the important point in the piece is the loadout details- 6 per tank. We are acquiring refleks ATGM's with the T90's...superior and the successor to the svir. It stands to reason that the refleks will be a frontrunner and the svir is out. A recent report,i'll check the BR news folder -referred to the Ukrainians offering their latest laser beam rider ATGM ..and said that the IA had a requirement of at least 2000 such missiles!Here.. <A HREF="http://www.bharat-rakshak.com/LAND-FORC ... -Sept.html" TARGET=_blank>http://www.bharat-rakshak.com/LAND-FORC ... pt.html</A> Ukraine offers new missile for Indian tanks (Defense News, 27 September 2001) Ukraine has offered to supply its newly developed laser-guided anti-tank missile for use by India's T-72 and indigenously-developed Arjun MBTs. A senior diplomat in the Ukranian Embassy in New Delhi said that Anatoly Kovalenko, Deputy Director General of Ukraine's arms export agency, Ukrspetsexport, Kiev, made the offer during a presentation in August to the Indian Ministry of Defence. The Ukrainian diplomat said the new laser-guided missile is based on, but is an improvement from, the Russian Combat laser-guided missile delivered to Ukraine in 1999. A senior Indian Army official said the service needs at least 2,000 laser guided missiles within the next two years. He said the Army is evaluating the Ukrainian proposal and a formal request to Ukraine will be soon for combat missile user trials in India. The official said Pakistan's T-80UD tank is armed with a 125mm gun that can fire a laser-guided missile, a capability that no Indian battle tank has. The diplomat said the Ukrainian missile has a maximum range of 5,000 meters and a high-explosive antitank warhead. The other point is equally subtle-the ERA part.It does fit well that the russians did give the initial ERA arrays(the article which started this thread) and the fact that the ERA performance is clearly stated here-degrades ATGM's by 80%!.May well be Kontact 5 and the transfer of tech to DRDO.2.Wrt,The stratmag article.Apparently the bhai log have removed some earlier links from their archive.Went through it with afine tooth comb now.The salient points from that article by Surya gangadharan-and i remember it well-(it mentioned that it was based on Defense News) were: The usual data of the various companies involved in the upgrade-given in the BR link given below.And what struck me was the statement that the T72 main gun was to be upgraded.The designation was not mentioned ,but the ones on our T72's are the older 2A46(perhaps M) and the latest variant is the 2A46M-2 on the T90. Interestingly,the BR equipment page( <A HREF="http://www.bharat-rakshak.com/LAND-FORC ... oured.html)also" TARGET=_blank>http://www.bharat-rakshak.com/LAND-FORC ... oured.html)also</A> quotes that the T72 will have a new gun stabilization system to be made by BHEL.This of course will have to be done to make the T72 able to fire on the move. Add this to the ammo....and we have some dramatic enhancement to the t72 firepower!To summarize,if only a few T72's are to be given REFLEKS capability,then it might make sense to even replace their main gun,even tho' it may not be technically needed.Go the whole hog approach!I have sent you the articles excerpts by Tehelka . 3.Ref: The APFSDS details/penetration issue...We have to consider two things since we are guessing certain parameters here! The DRDO's lack of all data is either an oversight or intentional.The 125mm APFSDS/T produced by POF....claims a muzzle velocity of 1730m/s and a penetration of 460mm at 2km range.link(.http://pofwah.com.pk/products.htm)This ties in with the kanwa report of the chinese supplied projectiles(inference -license produced by POF) not going above 460mm/480mm !!Ok.So we do know what is in service with the pakis today wrt their ALKhalids and AlZarrars.This of course disregarding the DU125MM round supposed to be manufactured by NDC.It also has details on the 105mm APFSDS-300 mm penetration-angle not given (This is a Kinetic energy fin stabilised round and can be fired from 105 mm L7 series rifled tank guns fitted on many current MBTs such as Leopard, Vickers MK1&3, M60 (manufactured under license in USA as M68) early M1, updated M48, Merkava and regunned T54 series, T 69).Comparisons...Regarding penetration details and the details in the DRDO website...it is clear that the information provided with the guessestimates states that the indian round is inferior to the Pof/Norinco one above.The data generated at zero incidence/obiquity at 2km for the indian 125 mm APFSDS=35+/- 6cm. Max=41 cm=410mm. The Pof/Norinco round states: 460mm at zero obliquity at 2km!The muzzle velocity for the POF/Norinco round is also greater than the indian one. 1730m/s compared to 1500-1550 m/s. BTW,Sanjay,it seems that the Indian APFSDS=Norinco round(given as 460mm at 2km) was in an International Defence Journal back issue,not a chinese mag!Cant get my hands on a IDR though...{Its also clear that all the russian rounds and the info i gave in a previous post are inferior to both the ones being discussed here.This also confirms your data that the russian ammo imported wasnt good enough for the IA and hence the indigenous project at HAPP...I'm taking the ammo imported to be of the older russian types i mentioned above...the max they can do is 250mm .}Now if the Tribune and the Directorate of Standardization "spin" is taken...that means a penetration of 36 cm RHA(triple heavy NATO is ~ 36 cm via Paul's post) at 3500 metres. Paul,could you determine what penetration it would have at 2Km?Greater than the previous data at any rate.Also,if the IDR info can be validated ,then at the very least ,we have parity with the chinese/pakis!So if the above are correct and parity/superiority is there,then the DRDO data is insufficient. If the guesses are right and the DRDO round is still not upto par(imho,doubtful) the T90 deal will signal an entire new range of russian APFSDS/HEAT rounds license produced over here. Provided the russians have them.The 120mm APFSDS is an unknown beast.CAG's last account-@1997 -states that the ammo was yet to be proven.The DRDO website says the ammo has performed admirably IN TRIALS....and this data came up on the website about a year back.So i do think the ammo performs as stated.Besides which,the CAG transcripts clearly establish that the army wouldnt have permitted batch production of 124 tanks till the arjun met the criteria which were lacking in the summer 97 trials.And the ammo was in doubt then.The same of course applies to kanchan/protection too. regards, nitin ps:Can you guys post the relevant excerpts fro the weaponsindia link?I keep getting a message of "this site is hosted by net4india etcetc"...and nothing else.

JCage · Post by **JCage** » 13 Nov 2001 16:08

And the 5km capable ATGM issue also brings us to the fact as to why the IA is so insistent on the same.As a counter to the PA T80UD's having it ..or more. If the actual situation makes the feasibilty of a greater than 2.1 km tank-tank matchup rare...then why have a huge and expensive store of main gun fired ATGM's? Or are they planning something sneaky?Tank guns acting like 155MM's with krasnopols...with spec ops designating targets?Rather doubtful as the krasnopol type items and the ATGM's have totally different laser guidance philosophies/eqpt/techniques.Sanjay,adding to your post about the T72 gun and its limitations.. The 2A46M-2 has a stated range with FCS=4km.The T90's will have french TI sights from sagem too. Regards, nitin

Peeyoosh · Post by **Peeyoosh** » 13 Nov 2001 16:18

NitinIn Rajasthan the sand is very soft, hard for tanks to function effectively, in the J&K gettinga 2000 m shot will be very very rare - in Punjab too there are bunds and ditches, tactical driving will ensure that such long range shots are very rare.Maybe range is less of a concern as opposed to making sure that shorter range shoyts - around 1.5- 2 km. ones, result in kills.Peeyoosh

Paul_L · Post by **Paul_L** » 13 Nov 2001 16:19

There are two significant variables in my estimate that definately could improve the penetration over all. Those are the V-Drop and the assumption of a sheathed penetrator. I was just looking at a 105mm APFSDS thats been developed for the Indian army that resembles the British L23 penetrator. I estimated diameter based on the exposed section, but in the british rounds this area is wider than the main body of the penetrator. While I assumed a constant diameter rod. I will look at that penetrator and see if this can be applied here. The Vdrop I'm not happy with any way.Andrew Jaremkow reported the 120m/s/km awhile back due to the drag provided by the hugh fins on both the BM-32 and 42. But when the BM-42m was developed with smaller fins the V-drop was reduced to 80-86m/s/km.I will make an estimate based on these cahnges and see where that takes us. It will also help to understand just why these details are so important....and are usually well guarded secrets

Paul_L · Post by **Paul_L** » 13 Nov 2001 17:17

An alternative to the above 125mm APFSDS analysis is that the penetrator is a scaled up improved version of the 105mm APFSDS already designed . This way the actual penetrator volume is ~ 75% of the volume of constant diameter rod based on 30mm x 15 L/d. Thus the volume is adjusted from 318cc down to 238cc = 4.17 kg penetrator and a 4.6kg in flight projectile. This would explain the reduced muzzle velocity. Thus the penetrator could be a 45cm 15:1 L/d tungsten alloy penetrator with a MV of 1550 m/s. The fins and design is improved to reduce drag and the V-Drop is assumed to be ~ 80m/s/km. The scaling and semi infinite conversion is as above with the Andersons formula adjusted as follows… 1.044 V – 0.194 x [In of L/d ] x 1.23 [scaling] + 3.9/7.8 . The 60° penetration estimate is an LOS penetration and the estimated penetration at range looks like …<PRE> Muzzle 1550m/s [ 1.55 x 1.044 – 0.737] x 1.23 = 1.08 x 45cm = 48.8 + 3.9/7.8 = 53± 7cm @ 0° & 57±8cm @ 60° 1000m 1470m/s [ 1.47 x 1.044 – 0.737] x 1.23 = 0.98 x 45cm = 44.1 + 3.9/7.8 = 48±7cm @ 0° & 52±7cm @ 60° 2000m 1390m/s [ 1.39 x 1.044 – 0.737] x 1.23 = 0.88 x 45cm = 39.5 + 3.9/7.8 = = 43±7cm @ 0° & 47±7cm @ 60° 3000m 1310m/s [ 1.31 x 1.044 – 0.737] x 1.23 = 0.77 x 45cm = 34.9 + 3.9/7.8 = 39±6cm @ 0° & 43±6cm @ 60° 4000m 1230m/s [ 1.23 x 1.044 – 0.737] x 1.23 = 0.67 x 45cm = 30 + 3.9/7.8 = = 34±5cm @ 0° & 38±6cm @ 60° </PRE>This round suggest Triple heavy NATO target can be penetrated at > 4 kms and represents the upper end of what this round can do.The penetration compares well with Polish Pronit APFSDS and BM-42 APFSDS and 80s technology German 120mm DM-23 & UK L-23.Their is still considerable room for improvement, for example most modern NATO 120mm rounds have V-Drops of only 60m/s/km and feature penetrators that are 30:1 L/d or more with penetrators 65-75cm in length. This could increase the penetration by over 50% above the estimated penetration.

Sanjay · Post by **Sanjay** » 13 Nov 2001 20:09

Paul, As far as I know, the penetrator is a scaled up version of the 105mm FSAPDS. All three rounds - 105, 125, 120 - were conceived at the same time. The 105 mm round wa the first into service and the 125mm was supposed to be a scaled up and improved version of the 105mm penetrator. That's why it took longer to develop. This aspect, you can be pretty certain on. Furthermore, your penetrator weights and that it is a tungsten alloy and the L/D ratio are all consistent with well known facts ( despite some uncertainty over the penetrator mass ). The 120mm round was designed to be superior to both the 105mm and 125mm. Nitin, the 5km range missile is really intended to trump the T-80. If the an international mag made the claim, take it seriously regarding 125mm FSAPDS.

JCage · Post by **JCage** » 13 Nov 2001 20:35

Now we are getting somewhere! The latest set of data generated by Paul appears much closer to what we have been aiming at.Sanjay, Yeah!The tandem warhead on the refleks should make the T80UD with its ERA toast at lower/battle ranges!That would be a guaranteed kill even if the APFSDS underperformed.re:IDR Apparently that 460mm@2km seems sort of like a benchmark which puts both the indian and the norinco round in the same league!The date of induction/timeframe for these two rounds seems to be the 90's according to some other things i dug up. Pretty creditable if this is the one they-the chinese- took israeli tech for.

Regards, nitin

Sanjay · Post by **Sanjay** » 15 Nov 2001 20:44

Paul, Can now confirm that 125mm penetrator is a scaled up and improved 105mm.The density of the tungsten alloy used is apparently 17.8g/cc. Would this increased density make any difference to your latest - and apparently accurate - calculations for 125mm FSAPDS penetration ?Look now, if you can, at data for the 120mm FSAPDS round: <A HREF="http://www.weaponsindia.com/mbtfsapds.htm" TARGET=_blank>http://www.weaponsindia.com/mbtfsapds.htm</A> Key to note is the increase in overall mass to 20.2kg, propellant weight to 8.46kg and muzzle velocity to 1650m/s.Again, the penetrator is an improved 105/125mm design.It should also be stated that this round is not yet in large scale mass production.

Paul_L · Post by **Paul_L** » 15 Nov 2001 23:43

<BLOCKQUOTE>quote:<HR>Originally posted by Sanjay: Paul, Can now confirm that 125mm penetrator is a scaled up and improved 105mm.The density of the tungsten alloy used is apparently 17.8g/cc. Would this increased density make any difference to your latest - and apparently accurate - calculations for 125mm FSAPDS penetration ?Look now, if you can, at data for the 120mm FSAPDS round: <A HREF="http://www.weaponsindia.com/mbtfsapds.htm" TARGET=_blank>http://www.weaponsindia.com/mbtfsapds.htm</A> Key to note is the increase in overall mass to 20.2kg, propellant weight to 8.46kg and muzzle velocity to 1650m/s.Again, the penetrator is an improved 105/125mm design.It should also be stated that this round is not yet in large scale mass production.<HR></BLOCKQUOTE> There are some tungsten alloys that are much stronger than the norm...just as their are tungsten alloys that are worse. The lesser capable ones are less than 17.4 g/cc and are generally about 0.05 P/L below the normal value . The improved alloys are 18.6g/cc and 17.45g/cc respectively [that I know of]. Generally their 'stonger' rods , but increased density could also be a factor.I would suggest that their is little difference unless the strength is also up.120mm we need specific projectile dimensions to anaylse this.

Sanjay · Post by **Sanjay** » 16 Nov 2001 01:23

Regretably, we don't have those. What we really have is what's at the weaponsindia site and that's all. All I can say is that the 120mmFSAPDS was designed to have greater penetrating powers than the 125mm. Wouldn't the increased muzzle velocity and overall weight seem to point to improved penetration over the 125mmm ? The penetrator is a souped up 125mm - just as the 125mm was a souped up 105mm. I strongly suspect that production of the 120mm FSAPDS is being conducted entirely by DRDO facilities at the moment. I wouldn't be surprised if the Arjun production cleared thus far is undertaken by CVRDE. I suspect, though can't prove, the strength of the penetrator is increased.

Paul_L · Post by **Paul_L** » 16 Nov 2001 02:18

<Quote> "Key to note is the increase in overall mass to 20.2kg, propellant weight to 8.46kg and muzzle velocity to 1650m/s.Again, the penetrator is an improved 105/125mm design." + 944mm round length </Quote> This info doesn't tell us much since most 120mm rounds have these velocities and projectile weights. The max length doesn't tell us much either because existing 105mm rounds are over 1 meter in length.I could try to use the propellant weight but only if this was an existing gun to compare to.Yes the 125mm APFSDS is a scaled up version of the 105mm round but its about 1 kg more in mass. Also the shape has changed from 12.8:1 L/d to 15:1 L/d penetrator.What do I assume about the 120mm APFSDS?Even if I had a reasonable pic of this round I could try to approximate the rod diameter, and from that and the assumed projectile mass work back to a approximate L/d....but the more of this approximation the less accurate and valuable the estiamte. Look how much difference the 125mm penetration estimate becomes based on a simple change in the penetrator material composition [ IE Sheathed as opposed to monoblock penetrator].

Sanjay · Post by **Sanjay** » 16 Nov 2001 02:39

In all probability 15:1 might have been retained. Other than that, there is no information, and even here we're guestimating.In terms of pictures, there is one at this link: <A HREF="http://www.weaponsindia.com/mbtfsapds.htm" TARGET=_blank>http://www.weaponsindia.com/mbtfsapds.htm</A> wait for the page to load completely, I don't know how much good it is for you.In terms of Muzzle velocity and mass, how does the round compare to the latest British tungsten FSAPDS round ? Also, how does it compare to the L-26 FSAPDS ?

Paul_L · Post by **Paul_L** » 16 Nov 2001 06:07

<BLOCKQUOTE>quote:<HR>Originally posted by Sanjay: In all probability 15:1 might have been retained. Other than that, there is no information, and even here we're guestimating.In terms of pictures, there is one at this link: <A HREF="http://www.weaponsindia.com/mbtfsapds.htm" TARGET=_blank>http://www.weaponsindia.com/mbtfsapds.htm</A> wait for the page to load completely, I don't know how much good it is for you.In terms of Muzzle velocity and mass, how does the round compare to the latest British tungsten FSAPDS round ? Also, how does it compare to the L-26 FSAPDS ?<HR></BLOCKQUOTE>Indian 120mm APFSDS-T [Tentative]India has developed a 120mm APFSDS from the same penetrator that is used in the 125mm APFSDS , which in turn is a development of the 105mm APFSDS mentioned above. What is known is not very much, the total round mass is 20.2kg and the MV is 1650m/s and the Vdrop could be in the 80- 60m/s region and the total projectile is 944mm long with the primer 425mm long…this means the projectile must be less than [ 944-425] = 52cm in length. The visible diameter of the projectile is roughly 19-20% of the sabot diameter or ~ 24-26mm. If we take the 125mm projectile as the start point the penetrator mass is ~ 4.2kg and the tungsten density is reported to be 17.8g/cc thus the penetrator volume is about 236cc.Since the penetrator diameter is ~ 24-26mm that suggests a continuous rod of 52-45cm in length for a L/d of 22-17:1. Now since the projectile has to be less than 52cm the thicker shorter rod looks more likely and the pic also suggest a certain amount of truncation in the nose design. I’d suggest a ~ 47cm penetrator with a L/d of 18:1 , which looks like a good developmental step up from 105mm with 12.8:1 to 125mm with 15:1 to 120mm with 18:1L/d.OK going on these assumptions, the semi infinite conversion should be 1.0d @ 0° & 2.0d @ 60° , with the scaling factor about 26/6.4 x 5% = 1.2 times . Thus the Andersons inputs should be 1.044V – 0.77 x 1.2 + 2.6cm @ 0° & 5.2cm @ 60°and the 60° penetration is an inline or LOS penetration.<PRE> Muzzle 1650m/s [ 1.65 x 1.044 – 0.77] x 1.2 = 1.14 x 47cm = 53.7 + 2.6/5.2 = 56± 9cm @ 0° & 59±9cm @ 60° 1000m 1570m/s [ 1.57 x 1.044 – 0.77] x 1.2 = 1.04 x 47cm = 49 + 2.6/5.2 = 52±7cm @ 0° & 54±8cm @ 60° 2000m 1490m/s [ 1.49 x 1.044 – 0.77] x 1.2 = 0.94 x 47cm = 44.3 + 2.6/5.2 = = 47±7cm @ 0° & 50±7cm @ 60° 3000m 1410m/s [ 1.41 x 1.044 – 0.77] x 1.2 = 0.84 x 47cm = 39.6 + 2.6/5.2 = 42±6cm @ 0° & 45±6cm @ 60° 4000m 1330m/s [ 1.33 x 1.044 – 0.77] x 1.2 = 0.74 x 47cm = 34.9 + 2.6/5.2 = = 38±6cm @ 0° & 40±6cm @ 60°</PRE> Its been suggested that the heavier tungsten alloy was selected because it was stronger which should increase penetration by 0.05 P/L at the subscale level…In addition it could be assumed that general improvements could include a slight reduction in the V-drop [to say 70m/s/km] over the 125mm APFSDS round. None of this is proven but if it is the case the following adjusted penetration is possible <PRE> Muzzle 1650m/s [ 1.65 x 1.044 – 0.77+ 0.5] x 1.2 = 1.2 x 47cm = 56.5 + 2.6/5.2 = 59± 9cm @ 0° & 62±9cm @ 60° 1000m 1580m/s [ 1.58 x 1.044 – 0.77 +0.5 ] x 1.2 = 1.11 x 47cm = 52 + 2.6/5.2 = 55±8cm @ 0° & 58±8cm @ 60° 2000m 1510m/s [ 1.51 x 1.044 – 0.77+ 0.5] x 1.2 = 1.03 x 47cm = 48..3 + 2.6/5.2 = = 51±7cm @ 0° & 54±7cm @ 60° 3000m 1440m/s [ 1.44 x 1.044 – 0.77+ 0.5] x 1.2 = 0.94 x 47cm = 44.2 + 2.6/5.2 = 47±7cm @ 0° & 49±7cm @ 60° 4000m 1370m/s [ 1.37 x 1.044 – 0.77 + 0.5] x 1.2 = 0.85 x 47cm = 40 + 2.6/5.2 = = 43±6cm @ 0° & 45±7cm @ 60°</PRE>

Sanjay · Post by **Sanjay** » 16 Nov 2001 19:38

Paul, thanks a lot. Your work in this regard is much valued. Now, how do these figures compare to the latest British tungsten alloy FSAPDS rounds - the last one I'd heard of was the L-26 - or is that with a depleted uranium penetrator ? How does it compare to the German DM-33 ?

JCage · Post by **JCage** » 16 Nov 2001 22:51

Paul, did you get my mail?

Hi Sanjay,A few points ...till paul chips in and tells us the latest. If you are referring to the Charm-3 -latest brit DU apfsds -that'll outperform the 120mm indian one by a substantial margin.The performance figures posted on tanknet previously put even the M829A1(ODS) better than the one here...leaving the M829A2,A3 out of the discussion.Speculative or not,this 120mm clearly out performs the paki round in their service at present.The data extrapolation appears to be pretty logical...so we *can* hope for the best.The 125mm apfsds-t manufactured by POF wah is indeed a norinco licensed type.(janes munition handbook-2000-2001). Other than this NDC pakistan displayed a 125mm DU APFSDS model at IDEX 2001 in the UAE.There appear to be no pics available other than a for a 105mm DU round mockup displayed at the same show. To give a comparison factor again...the chinese seem to have 2 "new" rounds with all the rumours floating around. One is a tungsten APFSDS,another a DU one. Also they claim that their 125mm in service,is an "improved" one with a longer barrel and able to sustain a higher muzzle velocity.Both these rounds-especially the first one-are derived from israeli advances. Details of the tungsten round from pauls previous posts-59cm long 27:1 L/d Tungsten APFSDS with 1.73 km/s velocity .Giving a max penetrative power of 64 cm at 2 km.(angle not specified). This is even better than a russian DU round-their current best-called the BM32 which outperforms the BM42 tungsten round.If the data generated for the 120mm apfsds is near the mark,it does 61 cm max at 2km(60 deg.)...not bad. And pretty creditable.However,whether it be the chinese rounds or the indian one-at 2km its pretty doubtful they can penetrate either of the rivals frontal armour...considering both alkhalid+era and the arjun+era.At closer ranges....I do have a distinct feeling DRDO is "underplaying" the 120mm and its indeed a much improved 125mm...with substantially better performance.DRDO/IA would have factored in the future threat assessment and then some.Wrt our new "acquisitions". This is what the T90 armament improves over the T72M1...from stratmag.This is from their No. 001/ Issue: July 15Armament: The main armament is a 125mm enhanced-accuracy smooth-bore gun mount featuring a built-in alignment system and an easily detachable barrel. The gun features better ballistic properties, has a longer range, uses better ammunition, can fire missiles and the fire control system has been improved to reduce first-round firing preparation time. Since "better" ammunition is mentioned ,TOT to OFB appears a distinct possibility. regards, Nitin

JCage · Post by **JCage** » 17 Nov 2001 00:14

Sanjay, Paul 'll have to give a rundown of the brit apfsds versions vs the HAPP one..Heres some more interesting info...paul mentioned the pronit apfsds earlier on..Also points to how clearly the data is "released" vs our secrecy...

Article from Defendory International 2000 Janes News N/w. New tip for Polish tank ammo The 125mm APFSDS (Armour-Piercing, Fin-Stabilised, Discarding-Sabot) round for the widely deployed Russian 2A46 smoothbore tank gun is now available with a 24.2mm high-penetration tip (right). The manufacturer, Pronit SA, claims that the new tungsten alloy-tipped round, the APFSDS-T, can penetrate steel hulls to a depth of 560mm from a range of 2,000m compared with a previous performance of about 460mm penetrative depth. Weighing 6.2kg, the charge (left) for the round is fitted with a GUW-7 electric-impact primer. With all components fitted, the projectile itself weighs 11.7kg, of which 3.8kg is the penetrator, 3.8kg is the secondary charge and the remaining 4.1kg is the tracer. According to the makers, accuracy error at 2,000m is to within 0.6m and strike drop at 1,000m range is under 70. It is understood that Poland has already manufactured a significant quantity of these 125mm APFSDS-T projectiles for an unidentified export customer for use with their T-72 MBTs. For the Polish Army T-72/T-90 MBTs, a new APFSDS-T projectile with increased penetration characteristics is now under development.And... Jane's Munitions Handbook 2000-2001 mentions: "It is known that 125mm tank gun ammuntion is produced in India but no information is available. A new muntions plant is being built at Bolangir in Eastern India which, when fully operational, will be able to produce 150,000 rounds of 125mm ammunition, presumably including APFSDS rounds, every year." (p.231). regards, nitin

Vick · Post by **Vick** » 17 Nov 2001 00:34

A question from a layman, me:If the T-90s and the T-72s are 125mm why the concern with the 120mm ammo?

Paul_L · Post by **Paul_L** » 17 Nov 2001 00:46

<BLOCKQUOTE>quote:<HR>Originally posted by Vick: A question from a layman, me:If the T-90s and the T-72s are 125mm why the concern with the 120mm ammo?<HR></BLOCKQUOTE>Because the 120mm gun is usually more power full gun and gets better penetration.

Vick · Post by **Vick** » 17 Nov 2001 00:58

Then the question is why would the Indian Army care about 120mm ammo when their current and future MBTs have 125mm guns?

George J · Post by **George J** » 17 Nov 2001 00:58

ya know all this mumbo-jumbo has the semblence of a nice BRM article. Would sanjay, paul and nitin care to volunteer? Oh and could you please have a section that goes somewhat like this for folks like me:T-72 good, T-80 better, T-90 with new ammo..da best.Coz if you use anderson's equations or ducovney's equations its all greek to me.

Paul_L · Post by **Paul_L** » 17 Nov 2001 02:04

<BLOCKQUOTE>quote:<HR>Originally posted by nitin: Sanjay, Paul 'll have to give a rundown of the brit apfsds versions vs the HAPP one..Heres some more interesting info...paul mentioned the pronit apfsds earlier on..Also points to how clearly the data is "released" vs our secrecy...

Article from Defendory International 2000 Janes News N/w. New tip for Polish tank ammo The 125mm APFSDS (Armour-Piercing, Fin-Stabilised, Discarding-Sabot) round for the widely deployed Russian 2A46 smoothbore tank gun is now available with a 24.2mm high-penetration tip (right). The manufacturer, Pronit SA, claims that the new tungsten alloy-tipped round, the APFSDS-T, can penetrate steel hulls to a depth of 560mm from a range of 2,000m compared with a previous performance of about 460mm penetrative depth. Weighing 6.2kg, the charge (left) for the round is fitted with a GUW-7 electric-impact primer. With all components fitted, the projectile itself weighs 11.7kg, of which 3.8kg is the penetrator, 3.8kg is the secondary charge and the remaining 4.1kg is the tracer. According to the makers, accuracy error at 2,000m is to within 0.6m and strike drop at 1,000m range is under 70. . regards, nitin<HR></BLOCKQUOTE>Thanks Nitn, yes I have your email but I take my time to answer where ever possible

Thanks for the info on the new Pronit, the original has a diameter of 28mm leading to an estimated penetration [Andersons]46cm @ 0°@ 2000m range, based on a 47cm long 19:1 L/d penetrator with a MV of 80m/s/km.What the Poles are doing to the Pronit , the Indians need to do to their APFSDS ammo . By reducing the penetrator diameter you increase the penetrator length. This does two things , it increases the penetration despite the fact that the higher the L/d the less efficent the penetrator. Plus it makes the velocity less of a factor in penetration than lenght....thus the loss of penetration down range[ which is a function of V Drop] has much less of an impact.Heres the anderson estiamted penetration of the Pronit as reported in JANES Ammo 2000/20001 The volume is ~ 218cc x 17.5= 3.8 kg, bang on for WHA density and projectile weight. JANES quotes the penetration @ 460mm @ 2km range and the MV is 1650 m/s, if we assume the V drop is an improvement over the BM32 then it could be 80m/s/km . The Andersons values should be - 0.78 [ L/d] x 1.19 [scaling] and the semi infinite conversion should be 2.5cm @ 0° & 5.0cm @ 60° , due to the truncation in the nose, and the 60° penetration is a line of sight penetration. The estimated penetration should be…... <PRE> Muzzle 1.65 ; 1.12 x 47cm = 52.6cm Semi infinite + 2.5/5cm = 55 ± 8cm @ 0° & 58 ± 8cm @ 60° 1000m 1.57 : 1.02 x 47cm = 47.9cm Semi infinite + 2.5/5cm = 50± 8cm @ 0° & 53± 8cm @ 60° 2000m 1.49 : 0.92 x 47cm = 43.2cm Semi infinite + 2.5/5cm = 46± 7cm @ 0° & 48± 7cm @ 60°</PRE> The Pronit is reported by Article from Defendory International 2000 Janes News , to be an improved Pronit penetrator with a maximum diameter of only 24mm and a Vdrop of 70m/s/km . The penetrator volume is 218cc and based on 24mm diameter a continuous cylinder should end up being >47cm [218÷4.6] .However if this is like the original Pronit, the penetrator main diameter is less than the maximum 28mm [24mm] , thus the improved model should have a average diameter of 22mm thus leading to an assumed length of 57-58cm [218÷ 3.8] for an L/d of 26:1. JANES quotes the penetration @ 560mm @ 2km range and the MV is 1650 m/s, and the V drop is 70m/s/km . The Andersons values should be - 0.844 [ L/d] x 1.189 [scaling] and the semi infinite conversion should be 1.3d@0° & 2.6d @ 60° 3.1cm @ 0° & 6.2cm @ 60° and the 60° penetration is a line of sight penetration. The estimated penetration should be <PRE> Muzzle 1.65 ; 1.04 x 58cm = 60.6cm Semi infinite + 3.1cm / 6.2cm = 64 ± 10cm @ 0° & 67 ± 10cm @ 60° 1000m 1.58 : 0.96 x 58cm = 55.5cm Semi infinite + 3.1cm / 6.2cm = 59± 9cm @ 0° & 62± 9cm @ 60° 2000m 1.51 : 0.87 x 58cm = 50.5cm Semi infinite + 3.1cm / 6.2cm = 54± 8cm @ 0° & 57± 8cm @ 60° 3000m 1.44 : 0.78 x 58cm = 45.5cm Semi infinite + 3.1cm / 6.2cm = 49± 7cm @ 0° & 52 ± 7cm @ 60° </PRE>So by reworking the shape of the penetrator they get a more aerodynamic shape and 8-9cm more penetration from essentially the same projectile.India should be able to do the same thing!If this was to be maximized to a 35:1 L/d penetrator that would end up with a 695mm x 20mm continuos rod penetrator with a V drop of ~60m/s and lead to the following assumed penetration @ 2kms range .<PRE> 2000m [1.53x 1.044-0.9] x 1.156 : 0.806 x 69.5cm = 56.0cm Semi infinite + 2.6cm/ 5.2cm = 59± 8cm @ 0° & 61± 9cm @ 60° </PRE>But here we run into a brick wall because the 125mm autoloader is limited to projectiles with a max length of 70cm . That means the max penetrator size should be about 65cm!Thats one of the reasons why the 120mm is better because it would have no such limitation, current NATO 120mm ammo has 80cm long projectiles with 75cm long penetrators.

Sanjay · Post by **Sanjay** » 17 Nov 2001 02:29

So Paul, how does the Indian 120mm FSAPDS compare to British Tungsten rounds and the German DM-33 ? At first glance, the round seems superior to the L-23 UK FSAPDS round and equal to the DM-33 - is this correct ? The 120mm round is important as it represents a technological achievement. Anybody who's familiar with the state of Indian defence metallurgy would appreciate the fact that the good performance achieved by these rounds is important.Paul, another poser - based on what is known about the Indian 105mm FSAPDS round, how does it compare with its contemporary rounds made in the 1980s ?

JCage · Post by **JCage** » 17 Nov 2001 02:53

Thanks Nitn, yes I have your email but I take my time to answer where ever possible

Heck, i got greedy.

A few random questions... 1.The zero incidence/obliquity refers to the angle b/w the penetrator tip vs the armour surface,right?So at zero degrees,its a plain theoretical value-that is the penetrator is parallel to the armour surface...aint possible-hence theoretical?And minimum penetration occurs at this point/angle.2.As this inclination increases,so does the penetration.So this is the principle behind sloped armour-that as the armour inclination increases,so does the chance of the projectile hitting the armour at almost zero degrees...almost parallel and "glancing" off with minimum penetration?3.The HESH wrt anti tank use depends on spalling,right?Knocking off the tank from inside-fragmentation. How much would an anti spall liner protect the tank?4.What is the normal accepted % hit probability for firing on the move wrt western tanks-like the M1A2,Leclerc etc?Regards, nitinPS:The bolangir plant is the most modern OFB one to date.It was setup with assisstance eprovided by the yanks-their machinery,tooling etc.Come pokhran 2 and off tehy went.But the plant was commissioned thereafetr by indian techs.Most reports have put bolangir as our newest plant for 155mm HE shells.

Sanjay · Post by **Sanjay** » 17 Nov 2001 02:56

Nitin, India uses HESH rounds against bunkers and other fortifications. The effect - I am told - is devastating. The 105mm field guns are also issued with HESH ammunition for this role. Also, the Leclerc achieves an 80%+ probability of a first round hit firing on the move at 1500 metres. In static firing, a similar figure is achieved at 2000 metres. This figure I read in a Greenhill Military Manual - Battle Tanks and Support Vehicles published in 1994.

JCage · Post by **JCage** » 17 Nov 2001 03:15

sanjay, Yeah, the 120mm rifled was chosen for this...but was wondering how well a HESH would work against a tank with spall protection.

Regarding the fcs dynamic shot%-great

!Unlike what i thought,the difference b/w what has been achieved and what should be isnt heaven and earth. Referring of course,to the defenseindia link about arjun getting 70% in trials and remaining a prototype. For what its worth-the production ready T90-2/MBT-2000/AlKhalid was offered for export with NORINCO claiming 71% PK in dynamic conditions! Guess the IA has different standards compared to our friends a/c the border! Regards, nitin

Vick · Post by **Vick** » 17 Nov 2001 04:08

nitin, I still don't understand why the IA would be interested in a 120mm ammo when their guns are 125mm? Am I missing something obvious?

Bishwa · Post by **Bishwa** » 17 Nov 2001 04:09

The Arjun gun is 120 MM

JCage · Post by **JCage** » 17 Nov 2001 04:13

Vick, The arjun has a rifled 120mm gun whereas the t72's/T-90's have a smoothbore 125mm.The older ones-T55's/Vijayanta's have 105mm guns of brit manufacture.regards, nitin

JCage · Post by **JCage** » 17 Nov 2001 04:22

<A HREF="http://www.drdo.org/labs/material/dmrl/achieve.shtml" TARGET=_blank>http://www.drdo.org/labs/material/dmrl/achieve.shtml</A> Salient points... 1.Kanchan, Composite Armour for Vijayanta and Arjun Tanks The state-of-the-art armour affords immunity against Heat, HESH and KE rounds at appropriate ranges and under different service conditions. Vijayanta has acquired significantly in-creased protection with Kanchan armour. The armour for MBT Arjun has been successfully tested against different threats.2. Heavy Alloy Penetrators : 105 mm FSAPDS A modern state-of-the-art plant with processing and inspection system has been set up.3.Steel Core 125 mm FSAPDS.

Paul_L · Post by **Paul_L** » 17 Nov 2001 06:17

<BLOCKQUOTE>quote:<HR>Originally posted by nitin: Thanks Nitn, yes I have your email but I take my time to answer where ever possible

Heck, i got greedy.

A few random questions... 1.The zero incidence/obliquity refers to the angle b/w the penetrator tip vs the armour surface,right?So at zero degrees,its a plain theoretical value-that is the penetrator is parallel to the armour surface...aint possible-hence theoretical?And minimum penetration occurs at this point/angle.2.As this inclination increases,so does the penetration.So this is the principle behind sloped armour-that as the armour inclination increases,so does the chance of the projectile hitting the armour at almost zero degrees...almost parallel and "glancing" off with minimum penetration?.<HR></BLOCKQUOTE> No actually its the other way around in the west, 0° refers to a vertical plate while 60° refers to a sharply sloped plate.