Jump to content

110 mm british tank gun


saul
 Share

Recommended Posts

Old ROF, few pics:

...

gun with chalk incription "EXP28 Bovington Tank Museum" on top of it`s chamber

 

no 5 is experimental 120 mm gun, no 6 - 120 mm L1, no 7 - 120 mm L11, no 8 - experimental 120 mm gun for MBT-80 (but it does not look like EXP-28 - maybe it is EXP-19M7 or M13?); unfortunately I did not find any 110 mm there...

 

Uploaded with ImageShack.us

 

Many thanks for the photos.

1. Yes this definately looks like the EXP-28 ordnance. AFAIK this is the only RARDE design that utilised a bearing on the forward stepped mounting diameter. This was to allow forward extraction of the barrel from the mounting rather than having to go through the rear of the turret as on the Chieftain with the L11.

 

2. I assume that part of the barrels are below the 'ground' level shown, however based on the relative lengths of the L1 (~7m+) and L11 (~6.6m) barrels shown then No5 might well be an early EXP-3 which was based on the L11 but with Crossley pad obturation, and No8 as you say looks more like the EXP-19M13A intended for the XM1 - it appears to have the single large bearing diameter and shorter barrel length (about 5.5m I think).

 

Out of interest do you know what were the other barrels were?

Link to comment
Share on other sites

  • Replies 52
  • Created
  • Last Reply

Top Posters In This Topic

Seems to be there is an awful lot of the Centurion/Chieftain story in IDF service that really needs to be written down. Marsh Gelbardt knew Tal I believe, I really must ask him if he knows any more about it.

 

Ive a list somewhere of the various tank options looked at by the MOD in the 1975 timeframe, would anyone be interested if I posted it up? It was rather more diverse than the A/G FMBT and MBT80, though they were options touched on among others.

 

 

Stu, you are very right, that must be an interesting story about the Cent`s and Chief`s in IDF...maybe Marsh do it sometime in the near future ;)

 

The list about tank option´s sound´s very interesting, can you post it up?

 

many thanks

 

Harry

Link to comment
Share on other sites

Old ROF,

no 2 - 105 mm

no 3 - 105 mm

no 4 - 20 pdr of Centurion Mk 3

no 9 - 20 pdr

There is also no 1 and 10 (cannot be seen on my pic), both 76 mm. Every barrel got some projectile attached to it: no 5 - experimental 120 mm HEAT round, no 9 - APFSDS (might be experimental, core diameter is about 30 mm; unfortunately no other dimensions taken to ID it).

 

 

Stuart,

AFAIK in UK for quite long time (late 70`s) it was thought that T-72 got just RHA armour: circa 100 mm @65-70o glacis and turret front all cast of about 400 mm thickness. There is also a very interesting document where it is stated that it is very probable that T-64 got turbine engine.

Edited by Przezdzieblo
Link to comment
Share on other sites

Old ROF,

no 2 - 105 mm

no 3 - 105 mm

no 4 - 20 pdr of Centurion Mk 3

no 9 - 20 pdr

There is also no 1 and 10 (cannot be seen on my pic), both 76 mm. Every barrel got some projectile attached to it: no 5 - experimental 120 mm HEAT round, no 9 - APFSDS (might be experimental, core diameter is about 30 mm; unfortunately no other dimensions taken to ID it).

 

 

Stuart,

AFAIK in UK for quite long time (late 70`s) it was thought that T-72 got just RHA armour: circa 100 mm @65-70o glacis and turret front all cast of about 400 mm thickness. There is also a very interesting document where it is stated that it is very probable that T-64 got turbine engine.

 

 

Przezdzieblo: many thanks for that. I wasn't sure if these might have been some other experimental barrels as well.

 

RARDE (as was) used to have a collection of experimental barrels and their associated breeches for both artilley and tank applications that had been designed by them and manufactured (normally) in the ROFs over the years. These ranged from the early 105mm/110mm work through to the 120mm/140mm systems for tanks and also the different 155mm artillery systems.

 

These were located in the 'test-house' at Fort Halstead but I have no idea where these went to when DRA/DERA were privatised and they became DSTL & Qinetiq. They were definately no longer kept in the 'Test-House' as this was used for a completely different function post privatisation.

 

Out of interest the following report about modelling the UK 120mm tank system shoes that DERA apparently utilised a smoothbore version of the L30 for some test firing - obviously this was not compatible with the Rh smoothbore system.

 

2001-04: Use of an Instrumented 120mm Projectile for Obtaining In-Bore Gun Dynamics; DERA; D.Lodge.

DRIC reference ADp012483

Link to comment
Share on other sites

  • 5 weeks later...

Stuart the 110m EXP-7 and EXP-8 ordnance both utilised the existing 105mm L7 breech (not bad considering this started out as the 20-Pdr system).

 

The 110mm EXP-14 ordnance had a completely new breech designed and made specifically to suit the new weapon performance requirements. Here it is being used on a slave ordnance system mounted in a chieftain cradle and recoil system. (hope this works!)

 

As you can see it has a vertically opening block instead of the sideways opening block of the L7 ordnance.

 

Thanks Old ROF

You can find a fairly good picture of the 110mm gun in W.A.Clayden's paper, "UK Tank Gun Philosophy" published in International Defense Review, 10/1981, p. 1319.

I am puzzled by his statement "The UK fielded [in the 1975 trilateral evaluation] a 110mm APFSDS round fired from the EXP14-M1 gun" and that the gun outperformed the German (Rh 120mm) and US (M68)contenders.

Richard Ogorkiewicz's description of the trilateral evaluation (in his 1991 book) is quite different (see p.52 and p.74).

Saul

Link to comment
Share on other sites

Stuart the 110m EXP-7 and EXP-8 ordnance both utilised the existing 105mm L7 breech (not bad considering this started out as the 20-Pdr system).

 

The 110mm EXP-14 ordnance had a completely new breech designed and made specifically to suit the new weapon performance requirements. Here it is being used on a slave ordnance system mounted in a chieftain cradle and recoil system. (hope this works!)

 

As you can see it has a vertically opening block instead of the sideways opening block of the L7 ordnance.

 

Thanks Old ROF

You can find a fairly good picture of the 110mm gun in W.A.Clayden's paper, "UK Tank Gun Philosophy" published in International Defense Review, 10/1981, p. 1319.

I am puzzled by his statement "The UK fielded [in the 1975 trilateral evaluation] a 110mm APFSDS round fired from the EXP14-M1 gun" and that the gun outperformed the German (Rh 120mm) and US (M68)contenders.

Richard Ogorkiewicz's description of the trilateral evaluation (in his 1991 book) is quite different (see p.52 and p.74).

Saul

Link to comment
Share on other sites

Writing about "outperforming" is party true. During first round of trilateral gun evaluation in 1975 British gun showed the best in accuracy (with US on the second place) and the worst in penetration performance (FRG the best). Results of later trials with 120 mm were also very questionable.

Link to comment
Share on other sites

Thanks Old ROF

You can find a fairly good picture of the 110mm gun in W.A.Clayden's paper, "UK Tank Gun Philosophy" published in International Defense Review, 10/1981, p. 1319.

I am puzzled by his statement "The UK fielded [in the 1975 trilateral evaluation] a 110mm APFSDS round fired from the EXP14-M1 gun" and that the gun outperformed the German (Rh 120mm) and US (M68)contenders.

Richard Ogorkiewicz's description of the trilateral evaluation (in his 1991 book) is quite different (see p.52 and p.74).

Saul

 

It's been a while since I've read that article but I have a copy of it buried some where in my files.

 

From what I remember reading from various sources about these trials. For the initial shoot-off the three countries offered up different systems. The US used their existing 105mm M68 but using a new design of FSAPDS round; the UK proposed the 110mm system but used an APDS round; and the FRG used their 120mm smoothbore gun again with an FSAPDS round. As Przezdzieblo states the results suggested that the UK system gave the best accuracy results but worst target performance.

 

RARDE were apparently surprised by these findings and so for the later 're-match' they put forward their own design of FSAPDS round but, as there was no time to design a new 120mm ordnance, they used the existing 120mm L11 ordnance. This combination seemed to have given good accuracy and target performance considering it was a 'panic' design. This led to RARDE designing the higher performance EXP19 series of prototype ordnances which culminated in the EXP19M13A ordnance which was specifically configured to suit the XM1. However it was the FRG smoothbore system that was finally selected.

.

Link to comment
Share on other sites

Guest Charles

It's been a while since I've read that article but I have a copy of it buried some where in my files.

 

From what I remember reading from various sources about these trials. For the initial shoot-off the three countries offered up different systems. The US used their existing 105mm M68 but using a new design of FSAPDS round; the UK proposed the 110mm system but used an APDS round; and the FRG used their 120mm smoothbore gun again with an FSAPDS round. As Przezdzieblo states the results suggested that the UK system gave the best accuracy results but worst target performance.

 

RARDE were apparently surprised by these findings and so for the later 're-match' they put forward their own design of FSAPDS round but, as there was no time to design a new 120mm ordnance, they used the existing 120mm L11 ordnance. This combination seemed to have given good accuracy and target performance considering it was a 'panic' design. This led to RARDE designing the higher performance EXP19 series of prototype ordnances which culminated in the EXP19M13A ordnance which was specifically configured to suit the XM1. However it was the FRG smoothbore system that was finally selected.

.

 

Old ROF, would this round become the L23A1 that was later deployed due to the BRIXMIS discovery that T-80 armour was damn good?.

 

TIA

 

Charles

Link to comment
Share on other sites

Old ROF, would this round become the L23A1 that was later deployed due to the BRIXMIS discovery that T-80 armour was damn good?.

 

TIA

 

Charles

 

I'm sure that the knowledge gained by RARDE in designing and developing this round would have been used when they came to design the OE L23, as they continued to use the standard APDS round as the main KE nature in the L11 gun. Also I'm seem to remember reading in an old report that the experiences of developing the 105mm L64 by, and with, the ROF Ammunition Division was also a contributor, unfortunately I can't remember where. There was always a close working relationship between RARDE and the ROF's during development of both ammunition and ordnance.

Link to comment
Share on other sites

  • 2 weeks later...

Best description yet from an actual user of the gun

 

When I was at Kirk we had a Chieftain with a 110mm fitted. It used two piece ammunition - projectile and a combustible case that had a brass stub cartridge on the end. All that was left after firing was the stub case with a long primer in it - about same length as 105mm primer. I actually had the stub case for some years, I gave it away about two years ago. I could probably get him to photograph it for me.

 

We were doing toxicity trials prior to live firing and I believe the gun was eventually entered into the American competition to source a new gun for M1. As you know they didn't choose it. By all accounts it was very accurate and quite effective. We just fired flat head proofs but I remember how effortless it was to initially open the breech, had like a fold out opening lever that you could operate with one hand.

 

I last saw the gun at Lulworth in the eighties, it was in the plate room at the end of the CIM building. I think the tank museum may now have it.

very intetesting.

can you remember the year in which the test firing took place?

you are the first to mention a two piece ammu.

thanks

saul

Link to comment
Share on other sites

No problem, In fact I think it was commander you should really be thanking. I seem to recall it was he who found that snippet at the National Archive. Seems to be there is an awful lot of the Centurion/Chieftain story in IDF service that really needs to be written down. Marsh Gelbardt knew Tal I believe, I really must ask him if he knows any more about it.

 

Ive a list somewhere of the various tank options looked at by the MOD in the 1975 timeframe, would anyone be interested if I posted it up? It was rather more diverse than the A/G FMBT and MBT80, though they were options touched on among others.

 

I seem to recall there is an L30 prototype in a photograph displayed on a plinth at what I believe is Shrivenham. I shall have to have a look on Google Earth and see if its still there.

i will be most gratefull if you post the list.

i am writing a paper in memory of the late general tal.the last part of the paper deals with a very hypothetical question : what could have happend

to rof and imi if the british fo went along with tals idea(in 1970)to develop a market for the 110 mm gun.

the list and any comment will be much appriciated.

saul

Link to comment
Share on other sites

very intetesting.

can you remember the year in which the test firing took place?

you are the first to mention a two piece ammu.

thanks

saul

 

Saul.

I can confirm that the EXP14 was separately loaded and used two part ammunition. The charge unit comprised a stub case with combustible case attached. The system was designed in about 1972 as part of the MBT-78 program which was later re-designated the MBT-80. The first round of the tri-lateral trials took place in 1975, so testing and firing trials from static range stands and then modified vehicles would have been carried out prior to this. Commander will be able to confirm if he was involved before or after the initial shoot-off but I'm sure testing would have continued even while the 120mm EXP19M7 system was being developed as a replacement.

Link to comment
Share on other sites

  • 6 months later...

Back to the 1975 trials and the question who outperformed whom:

the competition was between 105 mm/APFSDS (XM735E1), 110 mm/APDS and 120 mm/APFSDS, plus HEAT rounds for all. German arrow proved the best in terms of penetration, with XM735E1 close and APDS far, far away. Targets was "T62" (projected level of protection of Soviet T-62), "T62M" (upgraded T-62/projected T-72) and so called Modern Technology Tank (possible future Soviet tank; although no special armour was involved, just thick conventional and spaced armour arrays).

 

In terms of accuracy results were opposite, but differences were not great (few %).

 

HEAT penetration trials were static only, with FRG again on top because of caliber and new explosive filler (no details about it).

 

 

Those results were used for official findings. But it was not the only shooting during evaluation. US and UK also presented so called Growth Potential projectiles: the former XM774, the latter experimental 110 mm APFSDS and modified HEAT. And that 110 mm APFSDS, as it is said, outperformed German competitor.

Due to rigids rules of evaluation, those results were not used "officially", but for sure a good performance of US DU projectile and tungsten UK arrow was enough to make some folks doubts it German option is the best. Hope for winning evaluation was one of reasons why UK decided to go with rush-programme of new technology rifled 120 mm.

 

 

It could be found that that "hot" UK 110 mm APFSDS was a base for next developments, 105 mm PPL64 (later L64) and 120 mm XL22 (which lead to L23?). The question is where did that UK APFSDS came from. It looks like British started that development not much before 1975 trials and it was ready enough in very short time. Looking on troubled US APFSDS programme, which started in mid 1950s, UK progress is incredible.

There are few options:

- UK started works on APFSSD much earlier than it could be read;

- UK borrowed some technology, probably from US (it was common later in 1970s, f.e. UK tested US DU cores for 120 mm ammo).

 

 

Comments, questions and (I hope) answers?

Edited by Przezdzieblo
Link to comment
Share on other sites

 

Comments, questions and (I hope) answers?

 

What's your source?

And what German APFSDS was used? It seems to be rather improbable that M774 and the unkown 110 mm APFSDS performed better than 120 mm DM13, even though the latter is rather weak. Regarding accuracy, Rheinmetall claimed that the 120 mm gun proved to be more accurate than the 105 mm L7A3 in German trials, but they didn't give any information about the rounds used.

Link to comment
Share on other sites

Sources are from TNA.

In 1975 only one model of German APFSDS was used. In 1976 - probably the same, a bit better engineered. It was proto-DM 13, with two-part tungsten core in steel sleeve.

XM774 performance in 1975 started thinking about DU as the best material for LPRs core. It proved better than composite tungsten-cored projectiles (XM735 and German one), especcially vs complex targets (f.e. NATO heavy tripple).

About accuraccy of Rheinmetall 120 mm vs any other gun: all depends on time scale, trial conditions, number of shots that counts etc. F.e. during early presentation of 105/120 mm German smoothbore guns to British (circa 1972/1973, probably connected with FMBT programme) 120 mm shown great consistency at one test, and failed to hit a target in second. Now think, if you are employee of Rheinmetall marketing, which trial results you will mention? :)

Link to comment
Share on other sites

  • 9 years later...

Any info on the muzzle velocity of the APDS fired by the 110 mm EXP-7 ?

The EXP-14's APDS is quoted at 1578 m/s (Cold War, Hot Science book).

And did the EXP-14 ever fired APFSDS ammunition ? As the EXP-14 was discarded in 1975 in favor of the 120 mm EXP-19M7 and later the EXP-19M13A in 1977.

Edited by Sovngard
yes
Link to comment
Share on other sites

I have a very poor scan of a group of pictures of some RARDE developed 120mm rounds which were displayed at a BAEE show, I think from an old issue of IDR magazine. Unfortunately no date identified but assume late 70's.

One of these showed three rounds. The associated blurb identified them as a 120mm APFSDS, a product improved 120mm APDS and a 110mm FSAPDS which it states "was used for development and demonstrated in the tri-lateral NATO gun firing trials, but now abandoned". This is interesting as I thought the UK only used APDS on these trials, but possibly used outside of the 'official' firing trials.

However if they had been working previously on fin rounds for the 110mm ordnances, this might help explain how RARDE so quickly managed to get an APFSDS round ready for the 120mm EXP19-M13A ordnance that were used for the later firings in the US.

Link to comment
Share on other sites

13 hours ago, Old ROF said:

I have a very poor scan of a group of pictures of some RARDE developed 120mm rounds which were displayed at a BAEE show, I think from an old issue of IDR magazine. Unfortunately no date identified but assume late 70's.

Improved Chieftain for Iran, International Defence Review, 1976 :

b6Qf3cP.jpg

fCJXdSv.jpg

ivJF4id.jpg

Quote

This is interesting as I thought the UK only used APDS on these trials, but possibly used outside of the 'official' firing trials.

However if they had been working previously on fin rounds for the 110mm ordnances, this might help explain how RARDE so quickly managed to get an APFSDS round ready for the 120mm EXP19-M13A ordnance that were used for the later firings in the US.

Further reading (International Defence Review, No. 6, December 1976) :

Jz6T4uR.jpg

Edited by Sovngard
Link to comment
Share on other sites

Thanks thats the pictures I was referring to, but a better quality than mine.

Is the gun image from an article by Bill Clayden from RARDE called something like "Philosophy of British gun design". I used to have a copy but lost it many years ago.

I seem to remember that at about the same time there were a number of articles also published about Rheinmetal's work and reasoning in developing their smoothbore system.

Link to comment
Share on other sites

On 6/11/2011 at 3:25 AM, JWB said:

JWB, I realise this is nearly 10 years on, but thanks for that recommendation, Id missed it in this book before.

I think we have an explanation here why in the report I own, they were using APDS rather than APFSDS as a benchmark.

Link to comment
Share on other sites

Over on the secret projects site I came across a video about the FMBT anglo-german  co-operation work.

It discusses a joint meeting held to discuss the way forward as FMBT was intended to look at a range of vehicle configurations and ordnance options.

In the middle of the presentation it provides some information about different ordnance being considered. The UK provided data on their

new 110mm system which they had built and tested previously. 

https://m.youtube.com/watch?v=BYMPjN3ubzc&feature=youtu.be

 

Edited to delete statement re figures quoted comparing different numbers.

Edited by Old ROF
Link to comment
Share on other sites

Sovngard,

in Bovington I saw data table from 1974, with figures on 110 mm gun for MBT-78. It was stated that muzzle velocity of it's APDS projectile was 1521 m/s.

 

Old ROF,

like mentioned few years ago, in 1975 round of trials 110 mm APFSDS was fired as demonstration of potential growth. Any results got from that were discarded and not counted as official. Hence UK failure in 1975... and impression on US side strong enough to try another round and give UK another chance. 110 mm APFSDS, AFAIR, was based on some US components, modified by UK side.

 

 

W. A. Clayden's article 'UK tank gun philosphy' (IDR 10/1981) is illustrated with one picture of EXP-14M1 and APDS round, only. Unfortunately, I cannot paste it here, because still got issues with forum. And yes, there were some nice and quite warm-blooded writing fencing between UK and FRG sides on 120 mm guns.

 

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share


×
×
  • Create New...