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Mr Simon
 Post subject: Olifant 120mm gun
PostPosted: 21 Nov 2013, 00:16 
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While discussing upgrade paths for olifant mbt, I was informed that the centurion chassis cannot handle a 120mm tank gun apparently even with dampeners recoil would overstress the suspension and the hull itself.

Supposedly the allowance for the Olifant 2 turret to fit the LIW 120mm was made in anticipation of a new chassis mount, the chieftain hull or a merkava derived hull being most likely candidates, then combined they would be in 60+ ton range and have necessary counter-mass to cope when firing the LIW's 120 mm gun.

The final assertion was that the olifant on the centurion chassis is a dead end primarily due to it's low weight. Its low counter-mass means suspension and hull bear excess force from recoil, apparently even newer modern dampeners and suspension systems wouldn't be enough to compensate for this.

Now the Questions
1. Is this legit, is 105mm the highest caliber tank gun the Olifant can mount ?

2. OMC claimed it could mount the Olifant 2 turret on an "upgraded Mk 1b" chassis but don't say what the upgrades are or whether the turret mounts the LIW 120mm gun. Anyone have info or pics of the 120 mm Olifant.
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H1017412
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 04:29 
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My understand is that the above is correct, 120mm on existing hulls is not possible.

My internet research suggests that a Mk 2 differs from a Mark 1B by virtue of additional armour, upgraded power pack and transmission, as well as image intensifier and fire control system. There are no pics of the 120mm Olifant simply because it does not exist.

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Eugene
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 09:02 
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H1017412 wrote:
My understand is that the above is correct, 120mm on existing hulls is not possible.

My internet research suggests that a Mk 2 differs from a Mark 1B by virtue of additional armour, upgraded power pack and transmission, as well as image intensifier and fire control system. There are no pics of the 120mm Olifant simply because it does not exist.


The LW 120 mm gun was trialled on a Olifant Mk2 - so pictures of that installation probably do exist. It is my understanding that the trials did not go further due to cost and the understanding at the time that no tank existed as a possible Olifant opponent that could not be dealt with by the 105 mm gun.

The major disadvantage of the big smoothbore gun was also barrel life reduces considerably over the 105 mm and these have to be replaced far more frequently. Trials showed that sometimes after as few as 50 rounds - or less than 10% of the designed life. Why sabot rounds wear out barrels so quickly has always been a bit of a mystery to me - but the US navy had the same problem with their 8 inch guns in the 1950s when they trialled a range of sabotted AP shells.

As to whether the 56 ton tank cannot handle the recoil of the 120mm gun - I do not know but I have my doubts. 120 mm guns have been fitted successfully on considerably lighter tanks.
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Roger the Dodger
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 09:31 
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As I understand it the problem is one of size rather than weight.
The Rheinmetall 120mm gun (let's stop fooling ourselves about DLS developing the gun by themselves - sanctions busting is no longer relevant) requires a substantially larger turret than the 105mm L7 gun. The Centurion chassis cannot accomodate a large enough turret ring to mount such a turret.
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Eugene
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 09:46 
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Roger the Dodger wrote:
As I understand it the problem is one of size rather than weight.
The Rheinmetall 120mm gun (let's stop fooling ourselves about DLS developing the gun by themselves - sanctions busting is no longer relevant) requires a substantially larger turret than the 105mm L7 gun. The Centurion chassis cannot accomodate a large enough turret ring to mount such a turret.


In the 1980s the current rage in tank fashions was to dispense with the turret altogether - many articles were written on the advantages of such a system - but after a few experimental vehicles in the US the concept died a death. Automagic systems do have a nasty tendency to fail at moments critique and at least, if you have the thing in a turret with you, application of a 4 pound hammer often gets it to reconsider and start working again!
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Mr Simon
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 13:14 
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From what i gather the LIW 120mm is a copy of IMI's 120mm rather than Rheinmetall's 120mm, the former being more compact and tweaked for low recoil with different recoil mechanism, more recoil travel, different lighter metal . Apparently forging and treatment process of the IMI/LIW 120mm had input from RSA metallurgist. Hard to confirm given data or even pics of the LIW 120mm I cannot find.

On the turret ring word is that the IMI/LIW 120mm was deliberately made compact to fit in place of the 105 mm and was test fired from both unmounted and mounted olifant turret.

Now earlier and contradicting the tank n gun mismatch I had heard that by adding new hydraulic retarders, a slotted style muzzle brake and greatly increasing recoil travel LIW had solved the recoil problem. To the point where mounting on even lighter vehicles was viable and it's from that program to mount the 120 that tweaks for the low recoil GT 7 came. A pic of LIW's latest 120 mm would come in handy clearing this up.
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curious george
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 22:29 
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Centurion Mk. 7/1 - World Of Tanks
wiki.worldoftanks.com/Centurion_Mk._7/1‎
Jul 15, 2013 - The Centurion was used as the basis for a range of specialist equipment, including combat engineering variants with a 165 mm demolition gun ...

*I have no ideas of the properties,etc of that gun,but may or may not be relevent to the discussion.
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Eugene
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 22:34 
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curious george wrote:
Centurion Mk. 7/1 - World Of Tanks
wiki.worldoftanks.com/Centurion_Mk._7/1‎
Jul 15, 2013 - The Centurion was used as the basis for a range of specialist equipment, including combat engineering variants with a 165 mm demolition gun ...

*I have no ideas of the properties,etc of that gun,but may or may not be relevent to the discussion.


More in the nature of a short-barreled howitzer. Used for clearing obstructions, fortifications, etc. You will notice it was fitted with a dozer blade. Drop us a PM and I'll send you a photo.
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Eugene
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 22:46 
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Eugene wrote:
More in the nature of a short-barreled howitzer. Used for clearing obstructions, fortifications, etc. You will notice it was fitted with a dozer blade. Drop us a PM and I'll send you a photo.


Google Centurion AVRE and select "images" - there are plenty of pictures of the tank with the 165mm gun. Wiki has data on the L9 165mm gun.
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Mr Simon
 Post subject: Re: Olifant 120mm gun
PostPosted: 21 Nov 2013, 22:49 
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C'mon guys someone must have a photo even one of the LIW's 120 unmounted would be nice.

Now in addition I am told china's BK-1990 AFV was built off RSA's designs for the Rooikat 120 more so the turret. It also has some sort of semi-auto loader originally designed for the Olifant and the gun itself is a copy of LIW's 120 mm. Any info on this ?

From texts I gather the centurion 165 mm was a purely demolition tool with very low muzzle velocity and range, a large grenade launcher basically. A high velocity 165 mm would probably be well in excess of what the centurion could take.
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sob
 Post subject: Re: Olifant 120mm gun
PostPosted: 23 Nov 2013, 11:01 
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the MK2 is 62 tones so it is not due to recoil or any think like that, the orginal M1 used a 105mm gun and swapped to a 120mm with littel problem.

I would think not going to 120mm on the MK2 is more due to numbers and cost. Has in we do not have enough MK2s to make it worth the cost to fit a 120mm. Think about it we will now need a new ammo supply line and everything for less than 40 tanks.

another problem with going to the 120mm in a MK2 is a dramatic reduction in amount of ammo carried.


Now if the armscore can get there dick out there ass and parliament properly funds the SANDF the army is planning on 130+ new MBTs(leopard 2A based MBT seems most likely) and that seems like enough to warrant going to a new gun, and who knows we could upgrade our remaining MK1bs to MK2s use MK1a's has spare parts and give them 120mm and give them to the reserve force.


People like to say our tank is a 1945 design but this is incorrect, comparing the Mk1a is all ready a major upgrade, the MK1b is all most a new tank and the MK2s are the best MBT in sub saharan africa. i do not see any reason why the MK2 could not be used for awhile longer. maybe a MK2a is needed.


by the way the GT7 105mm gun using denel sabot rounds can penetrate 450mm of RHA at 3000m about 350mm less penetration has a L55 120mm gun. The only big increase for use is bigger HE rounds since we can handle any likely armour we may face in the next 20 years or so.
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curious george
 Post subject: Re: Olifant 120mm gun
PostPosted: 23 Nov 2013, 15:05 
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Discussing things like armour penetration,etc are indeed very interesting topics of conversation,BUT most of it purely academic as tanks nowadays seldom meet other tanks on the battlefield.

*off topic/thread drift

Yes,there is nothing as scary on the battlefield,etc we know that and isnt disputed.

"How are (our)tanks (most likely)to be deployed?" is the question we should be asking surely.

Are we talking "Kursk" or are we thinking "Falluja",ie 100's/1000's of afv's or a single squadron/troop assualting some/a single strongpoint?

Can we sustain these assets under difficult combat conditions,etc.

Other things to perhaps consider:Most tanks(any armour) will/would most likely be prioritised by OPFOR arty and aerial assets(if available) to neutralise/counter both perceived and actual "psychological" and physical impact.

Would you WANT to face any armour(incl tanks) eg on foot?Not very likely a "yes",but armour becomes very/more vulnerable in urban enviroments,eg how effective/vulnerable is a tank without its support elements,or its tracks(under fire) and or its fuel (re)supply?

What you think?
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curious george
 Post subject: Re: Olifant 120mm gun
PostPosted: 23 Nov 2013, 15:24 
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Roger the Dodger wrote:
As I understand it the problem is one of size rather than weight.
The Rheinmetall 120mm gun (let's stop fooling ourselves about DLS developing the gun by themselves - sanctions busting is no longer relevant) requires a substantially larger turret than the 105mm L7 gun. The Centurion chassis cannot accomodate a large enough turret ring to mount such a turret.


One approach could be similar to:

The Falcon turret was indigenously developed by King Abdullah II Design and Development Bureau (KADDB) in close partnership with the Mechanology Design Bureau and IST Dynamics of South Africa. It also uses some British and Swiss sub-systems. The Falcon turret was first revealed in 2003.
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sob
 Post subject: Re: Olifant 120mm gun
PostPosted: 23 Nov 2013, 15:25 
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curious george wrote:
Discussing things like armour penetration,etc are indeed very interesting topics of conversation,BUT most of it purely academic as tanks nowadays seldom meet other tanks on the battlefield.

*off topic/thread drift

Yes,there is nothing as scary on the battlefield,etc we know that and isnt disputed.

"How are (our)tanks (most likely)to be deployed?" is the question we should be asking surely.

Are we talking "Kursk" or are we thinking "Falluja",ie 100's/1000's of afv's or a single squadron/troop assualting some/a single strongpoint?

Can we sustain these assets under difficult combat conditions,etc.

Other things to perhaps consider:Most tanks(any armour) will/would most likely be prioritised by OPFOR arty and aerial assets(if available) to neutralise/counter both perceived and actual "psychological" and physical impact.

Would you WANT to face any armour(incl tanks) eg on foot?Not very likely a "yes",but armour becomes very/more vulnerable in urban enviroments,eg how effective/vulnerable is a tank without its support elements,or its tracks(under fire) and or its fuel (re)supply?

What you think?


our tanks would likely be deployed like they where in seboka, a company being attached to a mech battalion.

We unlicky to fight any other MBTs but the main job of a tank is supporting the infantry, that why so many are in afghanistan, taliban does not even have any AFV but tanks were still brought in.

Yes tanks become a priority target, because they so deadly.

Tanks do work in cities but they are in far more danger and need a lot of support.


We must all so not be succerd in to preparing for yesterday's war. Just because we are fighting rebels now does not mean we may not fight a army tommorow.



basically tanks are good, we need good tanks, not massive numbers but at least a brigade worth and they need to be good tanks.
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leading edge
 Post subject: Re: Olifant 120mm gun
PostPosted: 25 Nov 2013, 21:02 
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Ok, some points.

The Olifant chassis is not the Centurion chassis.

Certainly the hull is, but the Centurion running gear was completely changed to a torsion bar system.
Watch a few videos of a Centurion and an Olifant Mk1B driving over an obstacle, and you will see this is the case as stated by Armscor themselves.

The suspension was redone because the Mk1B is approaching twice the speed of the Centurion, and at 58 tons, is about 7 tons heavier.

Mounting a 120mm is definitely not a function of it's weight or suspension.

On the turret ring.
This I cannot say definitively. I do know the original Centurion turret ring was about 1.9m.

But consider the following:

GT1 - ? (possibly 20 pounder fitted to Centurions as purchased?)
GT2 - 90mm (Eland/Ratel)
GT3 - 105mm L7 for Olifant Mk1A
GT4 - 76mm (Rooikat-76)
GT5 - ?
GT6 - Smoothbore 120mm, upgradeable to 140mm for the TTD
GT7 - 105mm (GT3 development for Rooikat 105mm)
GT8 - Upgraded 105mm for Olifant Mk1B?
GT9 - Smoothbore 120mm for TTD (3 produced?)
GT10 - ?
Gt11 - ?
GT12 - Lightweight low recoil 120mm for the Rooikat 120

This is one of the few descriptions I've seen, but it is from the internet, so should be treated with caution:

Quote:
The 120 mm smoothbore tank gun GT 9 has been developed by LIW for installation in MBTs in the 40 to 80 tonne class. The weapon was developed as a technology project to establish this capability in South Africa with development of 120 mm ammunition being carried out in parallel.

The GT 9 has a concentric hydraulic recoil system with separate eccentric hydropneumatic recuperators which are housed in the breech ring. The breech is of the semi-automatic type with a vertical sliding breech block.

The breech block is opened by means of a cam during run-up and the cartridge stub is ejected by means of two extractors. The cam can be set to manual mode which then prevents cartridge ejection during run-up. This facilitates the sealing of the system during BC warfare. A guardrail, incorporating a cartridge deflector, is mounted around the rear of the gun.

The barrel has a bayonet type thread to facilitate fast assembly and is autofrettaged in the high pressure regions to allow for the use of high pressure ammunition.

The 120 mm/52 calibre barrel is also fitted with a bore evacuator and a thermal shield with the latter having an efficiency in excess of 80 per cent. Provision has been made for the possible installation of a muzzle reference system and it is also possible to fit a muzzle brake.

The gun has been designed for use with ammunition using a semi-combustible cartridge case with a metal sealing stub.

Main weapon caliber (mm) 120
Barrel length (calibres) 53
Weight (kg) 3000
Recoil force (kg) 4000
Recoil stroke (mm) 400



There are plenty of vehicles, such as the Rooikat and Centauro, that have had 120mm guns developed or mounted for them.
These vehicles weigh less than half the Olifant, and are wheeled to boot.

So it certainly isn't a function of the suspension nor weight of the Olifant.
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