# A34 Comet - how soon could it have been ready?



## vinnye (Apr 13, 2013)

I know that the Comet was designed in 1943, and prototypes were ready in Feb 1944.
So how quickly could they have been in service? 
Historically, they were being issued in Dec 1944. and they were held back because of the Ardennes offensive.
But, could they have had some units ready for D Day?


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## fastmongrel (Apr 13, 2013)

The plan was that the Comet would have been in service for D Day. Problems getting the Meteor production line running meant that the Cromwell was at least 6 months behind schedule and this possibly pushed the Comet back 6 months as well.


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## davebender (Apr 13, 2013)

350hp engine which powered Churchill tank would work until a more powerful engine becomes available.

I think this is the real reason.
M4 Sherman - Wikipedia, the free encyclopedia


> U.S. also supplied 17,184 Sherman tanks to Great Britain



Lend Lease shipments of Sherman tank removed British incentive to build similiar size Comet tank. I'm surprised the project wasn't cancelled entirely. Then British tank development could concentrate entirely on the more advanced Centurion design, giving Britain a weapon which could compete with German Panther and Soviet T-44 (which became post-war T-54).


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## tomo pauk (Apr 13, 2013)

Roughly speaking, the Comet was 'determined' by 3 things: engine (along with transmission), suspension (type and layout) and gun (type and layout). For the engine, the Wikipedia says this:


> It would take considerable time for Rover to make ready production lines for the Meteor, and it was not until a few months later, in January 1943, that sufficient Meteor engines were available and the A27M Cromwell began production. The Centaur production design allowed for the later conversion to the Meteor engine and many Centaurs would be converted to Cromwells before use.



Looking at that, the Cromwell might be as well used during the landings at Sicily? Deleting Cromwell (the initial user of Meteor) in the meantime, of course.

The suspension type (Christie) was well known many years before Comet was introduced, so that should not interfere with earlier introduction.

The main gun makes the things tricky. Or not? 
The way the cannon was mounted (external mantlet, that is eating up the precious turret volume; instead of Panther, KV or T-34 'Dolly Parton' layout) precluded the workable installation of the 17pdr. Vickers would need to either build the 75mm HV (that was intended designed for the Cromwell, but it could not be fitted at the end!), or to develop the 77mm HV some 15-20 months in advance. Or, the tank designers could take a look at T-34 or KV tanks, and design a similar cannon installation to where the 17pdr would be installed.


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## vinnye (Apr 13, 2013)

Well if we could have a choice, a Centurion available for D Day would have been a real boost!

I appreciate that the philosophy for D Day was get as many tanks as possible landed - makes a lot of sense and hence the emphasis on the Sherman getting priority over new possible designs. But if I were a tanker, I would have appreciated a Centurion if I might come up against a Panther or Tiger!


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## davebender (Apr 13, 2013)

Could WWII era tank landing craft carry a tank as heavy as the Centurion? I suspect not. However the Centurion would have been very useful for post D-Day offensives such as Operation Goodwood.


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## tyrodtom (Apr 13, 2013)

The allies had several hundred LCT's that could haul up to 3- 50 ton tanks. 
How much does Ceturion Weigh ? 50-60 tons ?

And then there's LST's, but you wouldn't risk them in the early part of a beach assault.


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## fastmongrel (Apr 14, 2013)

Centurion Mk1 was about 40 tons though that was more of a production prototype. The Uparmoured Mk2 with cast turret was around 43 tons and the Mk3 which was the proper developed version with the 20 pounder was around 45 tons. The final British Army version the Mk11 which I trained on in 1975 was around 51 tons. There are no exact weights for Centurions as they were continually upgraded plus for example there were about 5 different versions of track which could be up to half a ton different in weight per track. 

You could always tell the driver out of a Cent crew because he was the one who looked like a body builder. There was no power assistance on the steering, brakes, clutch or on the crash gearbox and it took some muscle to drive.


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## Shortround6 (Apr 14, 2013)

tyrodtom said:


> The allies had several hundred LCT's that could haul up to 3- 50 ton tanks.
> How much does Ceturion Weigh ? 50-60 tons ?
> 
> And then there's LST's, but you wouldn't risk them in the early part of a beach assault.




If they could land Churchill's (especially the MK VII and some of the "Funny's") then a Centurion shouldn't have been too much trouble.


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## vinnye (Apr 14, 2013)

A neighbour of mine was a Cent driver - and as you said Shortround - short and stocky, now partially deaf as well. Dont know if the latter is due to his service or not - but suspect it must have been a factor?


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## yulzari (Apr 14, 2013)

The Cromwell was meant to have a HV Vickers 75mm (roughly comparable to the Comet's '77'mm) but while the guns designers assumed an external mantlet the turret designers went for an internal one so the gun was too long to fit into the turret. 

With the HV 75mm Vickers the Cromwell was functionally a Comet even if it differed in some ways.

Riding my hobby horse; if the UK had concentrated upon developing the Valentine for the first 5 years of the war a sloping glacis Comet could have been in prototype trials in late 1943 and mass production to replace the Valentine before the start of 1944. If the design resources of the nation had been put into it alone. They would have been the only tanks the Commonwealth would have needed. HV Vickers or 17 pounder.


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## yulzari (Apr 14, 2013)

vinnye said:


> A neighbour of mine was a Cent driver - and as you said Shortround - short and stocky, now partially deaf as well. Don't know if the latter is due to his service or not - but suspect it must have been a factor?


Yes, my brother has hearing difficulties due to Centurion/Chieftan driving. Ear defence was seen as non-macho in those days.


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## vinnye (Apr 14, 2013)

I have read from Wiki that the Soviets sent a T34 to the Aberdeen testing grounds for evaluation. This was probably a bit late to affect tank designs before D Day?
If the Soviets had maybe shared their prototype A34 from early 1940, the US and UK may well have been able to produce a better medium tank ready for D Day?

I agree on both points Yulzari - a better Valentine could and should have been a priority - 6 pdr to start with and sloping armour?
Also, the not wearing of ear defenders caused a lot of men in particular to suffer unnecessary hearing loss.


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## vinnye (Apr 16, 2013)

davebender said:


> Could WWII era tank landing craft carry a tank as heavy as the Centurion? I suspect not. However the Centurion would have been very useful for post D-Day offensives such as Operation Goodwood.



I agree Dave, having the Centurion would have been a real asset for Goodwood and all of the Caen operations.

I also think it may have made a difference to the link up operation to Market Garden?
Not saying it would have changed the result - but may have made an impact on the drive towards Arnhem?


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## fastmongrel (Apr 18, 2013)

Sweet sounds from the RR Meteor

_View: https://www.youtube.com/watch?v=53SFoCxM8GA_


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## vinnye (Apr 18, 2013)

That is one awesome sound from a tank!


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## vinnye (Apr 19, 2013)

That is a sweet sound from a tank!

Yulzari, did your brother get to drive a Conqueror tank?


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## yulzari (Apr 28, 2013)

My brother never drove a Conquerer but a colleague in local government used to be a Conqueror troop commander during his National Service. He said he could keep up with a Centurion over bad ground but you only wanted to fire from a hull down position as it took forever for the poor gunner to load the 2 part rounds so they acted as mobile anti tank guns not assault vehicles. The Centurion was a better package as soon as it upgraded from the 20 pounder to the 105mm.


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## Freebird (Apr 28, 2013)

vinnye said:


> I have read from Wiki that the Soviets sent a T34 to the Aberdeen testing grounds for evaluation. This was probably a bit late to affect tank designs before D Day?
> If the Soviets had maybe shared their prototype T34 from early 1940, the US and UK may well have been able to produce a better medium tank ready for D Day?



Uh, you do realize that the Soviets were allied with the Nazis in 1940, and the Communist agents/sympathizers in the UK were active in trying to disrupt UK war production as far as possible?
So any sharing any T-34 prototypes is a non-starter...



vinnye said:


> Well if we could have a choice, a Centurion available for D Day would have been a real boost!



Why not the Cheiftain? 



vinnye said:


> I appreciate that the philosophy for D Day was get as many tanks as possible landed - makes a lot of sense and hence the emphasis on the Sherman getting priority over new possible designs.



Th British didn't put a lot of design work on the Sherman, British tank production was on an independant course.



davebender said:


> 350hp engine which powered Churchill tank would work until a more powerful engine becomes available.
> 
> I think this is the real reason.
> M4 Sherman - Wikipedia, the free encyclopedia
> ...



German tank development had fairly solidly outclassed the Sherman M1A1 by 1943, so certainly the British considered the Sherman a stopgap measure until the HV75mm Cromwell 17 pdr Challenger were produced in quantity for British armoured units.
The Cromwell Challenger (as envisioned) were more than capable of dealing with Panther tanks, and it's not even certain that stopping their development would speed up the Centurion (as built)


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## vinnye (Apr 28, 2013)

Yes, I was aware that Russia was allied to Nazi Germany in 1940. In fact they were right up until the time the Germans invaded them.
However, this does not mean that they trusted the Germans, far from it!
How else do you explain the fact that the Germans and Russians co-operated in exercise before WW2, and yet, the Germans were completly taken by surprise by the introduction of the T34?

Whilst saying that the Centurion would have been nice for D Day it was a stretch of what was possible, but had the powers that be co-operated with Russia and taken better note of the T34, maybe something better than what did arrive could have been available.

I also know that the British had very little to do with the design of the Sherman, apart from fitting a 17 pdr in it. The design work I was referring to was on Cromwell, Churchill and Comet designs.


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## vinnye (Apr 28, 2013)

Yulzari, from what I have been told by my neighbour, he liked the Conqueror, loved the Centurion and loathed the Chieftan!


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## tomo pauk (Apr 28, 2013)

freebird said:


> ...
> German tank development had fairly solidly outclassed the Sherman M1A1 by 1943, so certainly the British considered the Sherman a stopgap measure until the HV75mm Cromwell 17 pdr Challenger were produced in quantity for British armoured units.
> The Cromwell Challenger (as envisioned) were more than capable of dealing with Panther tanks, and it's not even certain that stopping their development would speed up the Centurion (as built)



We could note that there were other threats 'aimed' against tanks, from hand-held weapons up to different AT guns. Neither Cromwell, Challenger nor Comet were capable to shrug off that, neither were other Allied medium tanks.
Centurion did not broke any new ground in ww2 tank development, so canceling Cromwell/Challenger/Comet might've brought the 17 pdr heavy tank on the beaches of Normandy in June 1944.


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## razor1uk (Apr 28, 2013)

The Russians were sure that the Germans were developing bigger tanks like they were, but repeated Soviet delegations no matter what implied questions and hinted at slips of info could only fathom what turned to be largely the truth, certainly prior to '40; that the Germans didn't have anthing aproaching the T34 or KV1/2. Mind the Germans were probably thinking of the T-24/26's if they did catch the hints about '...anything larger than that tank over there?'.


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## yulzari (Apr 28, 2013)

Vinnye, as a one time foot soldier I loathed all tanks. Hated the sound of squeaking tracks nearby in the night and who thought that any sane foot soldier is going to walk up to the back of a tank that can't see you and may reverse at any moment and then stop to open up a telephone box on the back of the tank to attract the commander's attention before he squashes you. But I may be biased.......


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## vinnye (Apr 28, 2013)

When you put it that way Yulzari, I can see your point entirely!
On the other hand having some of your tanks around could be handy if the other side have some knocking about!


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## Freebird (Apr 28, 2013)

vinnye said:


> Yes, I was aware that Russia was allied to Nazi Germany in 1940. In fact they were right up until the time the Germans invaded them.
> However, this does not mean that they trusted the Germans, far from it!
> How else do you explain the fact that the Germans and Russians co-operated in exercise before WW2, and yet, the Germans were completly taken by surprise by the introduction of the T34?
> .



The Russians were rather hoping that the British the Germans would weaken each other so much that they could mop up the remnants.

They just didn't want to share anything with the West.


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## tomo pauk (Apr 29, 2013)

Why would the Soviets share anything with the West, prior 22th June 1941?


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## Milosh (Apr 29, 2013)

freebird said:


> They just didn't want to share anything with the West.



Then why were a T-34 and a KV-1 sent to the USA?

http://www.oocities.org/pentagon/qu.../evaluation_of_russians_tanks_at_aberdeen.htm


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## Shortround6 (Apr 29, 2013)

Sending 1940/41 tanks to The US at the end of 1942 isn't really sharing a whole lot. Soviets have been getting Western weapons for well over a year.


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## vinnye (Apr 29, 2013)

The T34 was so much better than anything the Allies had, it would have been nice to have had it in 1940, but as previously posted the Russians were allied with Germany at that point.


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## Freebird (Apr 29, 2013)

Milosh said:


> Then why were a T-34 and a KV-1 sent to the USA?
> 
> Evaluation of tanks T-34 and KV by workers of the Aberdeen testing grounds of the U.S.



They did indeed, but at the end of 1942, too late to be engineered produced in Britain before D-day.
The Soviets were reluctant to share much information with the west due to suspicion of our motives. (even as we were helping them)


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## razor1uk (Apr 29, 2013)

In a way, after Hitler back-stabbed them (in their/Stalins eyes, before he got the chance to do it to them), its sort of obvious they'd be holding back on technology sharing with their 'enemies enemy'. 
Not to defend the Soviets ourright, but to offer a possible more neutral bias a logical reasoning, if the roles were reversed, I think any country including the U.S. would be just as 'cagey'.


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## parsifal (Apr 29, 2013)

Shortround6 said:


> Sending 1940/41 tanks to The US at the end of 1942 isn't really sharing a whole lot. Soviets have been getting Western weapons for well over a year.



I agree, for the most part, but would the Us have benefitted if they had built copies of the T-34, perhaps with US engines,optics and transmissions? I think the t-34 was at least a generation ahed of US tank development at that stage of the war....


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## razor1uk (Apr 29, 2013)

Yep Parsifal, I think with the T34, the Soviets (design wise) jumped ahead of everyone by one generation, and perhaps another one production wise too; even if it was a little rough and ready, it was also tough and ready. Didn't they 34's also have rail mounted engine/transmission packs.


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## parsifal (Apr 29, 2013)

dont know. i do know thay had aliminum cast engine heads something pretty revolutionary for their time. T-34s acquired a terrible reputation transmission wise, and a great reputation for ease of maintenance. There was a lot of "stretchability" in the design. with influences showing all the way through to the T-72.


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## Freebird (May 2, 2013)

parsifal said:


> I agree, for the most part, but would the Us have benefitted if they had built copies of the T-34, perhaps with US engines,optics and transmissions? I think the t-34 was at least a generation ahed of US tank development at that stage of the war....



I don't know that it's really that helpful. Using some of the better design points (sloped armour etc) on future US tanks certainly, but the Soviet tanks had some mechanical problems that didn't give them a long lifespan, and would need to be re-designed

From the link posted earlier...

Evaluation of tanks T-34 and KV by workers of the Aberdeen testing grounds of the U.S.



> Engine: The deficiency of our diesels is the criminally poor air cleaners on the T-34. The Americans consider that only a saboteur could have constructed such a device. They also don't understand why in our manuals it is called oil-bath. Their tests in a laboratory showed that:
> - the air cleaner doesn't clean at all the air which is drawn into the motor;
> - its capacity does not allow for the flow of the necessary quantity of air, even when the motor is idling. As a result, the motor does not achieve its full capacity. Dirt getting into the cylinders leads them to quickly wear out, compression drops, and the engine loses even more power. In addition, the filter was manufactured, from a mechanical point of view, extremely primitively: in places the spot-welding of the electric welding has burned through the metal, leading to leakage of oil etc.
> 
> ...



The Soviets were fine with a tank that would only be used for a few hundred km, as it was more or less disposable. The US on the other hand, was going to considerable effort expense to ship tanks over the ocean, so wanted a tank to last longer than Soviet tanks.

The main problem with US tanks wasn't the lack of design options, it was the doctrine that precluded a more effective tank


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## vinnye (May 2, 2013)

According to Wiki, the T34 was pretty reliable :
Koshkin's team completed two prototype T-34s in January 1940. In April and May, they underwent a grueling 2,000-kilometre (1,200 mi) drive from Kharkiv to Moscow for a demonstration for the Kremlin leaders, to the Mannerheim Line in Finland, and back to Kharkiv via Minsk and Kiev.[21] Some drivetrain shortcomings were identified and corrected.


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## Shortround6 (May 2, 2013)

The Russians seem to have a history of prototypes performing much better than production examples. 

Of course there is also the question of what an experienced driver could do compared to a driver with minimal training. 

For those of us that remember manual transmission cars a question or two.

How many of us can remember a friend or relative that could get 60-100,000 miles on one clutch?
How many of us can remember a friend or relative that could ruin a clutch in 12-20,000 miles? 

and that is for cars weighing 1-2 tons and small engines compared to a tank engine, it also is for transmissions that for the most part were synchronized (at least on the upper gears). 

I used to drive a couple of fire trucks with non-synchro transmissions (30 years ago and they were left overs then) and if you blew a shift the best thing was to come to a complete halt and start in 1st gear again. Granted we weren't being shot at but we were responding to emergencies. Blowing the transmission doesn't get you to the fire


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## davebender (May 2, 2013)

Britain received 17,000 sherman tanks. It's reliable and has decent cross country performance. 

7.5cm/48 KwK 40 cannon fit into turret of 18 ton (original weight) Panzer IV. A similiar British made cannon should fit into larger Sherman turret without difficulty. 

Germany welded 30mm RHA plates to front of Panzer IVG. Larger Sherman tank should support similiar 30mm RHA plates without difficulty.

Problem solved. Britain just needs to build Sherman upgrade kit which includes better main gun and add on frontal RHA. With these two upgrades surviving British Sherman tanks can serve into the early 1950s.


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## fastmongrel (May 2, 2013)

Shortround6 said:


> I used to drive a couple of fire trucks with non-synchro transmissions (30 years ago and they were left overs then) and if you blew a shift the best thing was to come to a complete halt and start in 1st gear again. Granted we weren't being shot at but we were responding to emergencies. Blowing the transmission doesn't get you to the fire



I used to drive an old ex Army AEC Scammel 6x4 breakdown truck with crash box and that was shall we say a bit pot luck which gear you got. Luckily it was so low geared going from 2mph in 1st to a wobbling roaring 20mph in top 6th gear that it didnt really matter which gear you hit as long as it was generally in the right place. It could however have towed the Moon backwards if a long enough chain had been available.


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## tomo pauk (May 2, 2013)

davebender said:


> Britain received 17,000 sherman tanks. It's reliable and has decent cross country performance.
> 
> 7.5cm/48 KwK 40 cannon fit into turret of 18 ton (original weight) Panzer IV. A similiar British made cannon should fit into larger Sherman turret without difficulty.
> 
> ...



The 'similar British made cannon' could be the 75mm HV or 77mm HV, however the British have made extra effort, with the 17pdr installed in the Sherman Firefly. An interesting proposal might be equipping the US built 3in/76mm cannons with APDS ammo, the AP performance should be along the 77mm HV. 

This table might show why the Sherman was able to take the hefty powerful 17pdr - the turret ring was of generous dimensions (open the table in separate tab for hi-res):


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## davebender (May 2, 2013)

WWII era APDS ammo was inaccurate to the point where a 1944 U.S. Army test concluded standard AP was overall superior. Germany must have reached a similiar conclusion as APDS ammo was not mass produced despite several development programs including APFSDS from smoothbore cannon. I prefer tank cannon able to hit the broad side of a barn so let's cross that option off the list. 

HE capacity is just as important as AP. U.S. Army considered their 76mm HE shell to be poor. Perhaps a better HE shell could have been designed but if that were possible then why didn't it happen historically? 

German 7.5cm/48 cannon has a good HE shell and decent AP performance in a relatively lightweight and inexpensive package. That's why it's my first choice for a WWII era tank / AT cannon. 

British 77mm/50 cannon should work if Britain develops an effective HE shell for the weapon. Or else they could simply copy a captured German KwK40 cannon. Either way they need to get moving. British Sherman tanks should receive the upgrade before the end of 1943.


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## tomo pauk (May 3, 2013)

davebender said:


> WWII era APDS ammo was inaccurate to the point where a 1944 U.S. Army test concluded standard AP was overall superior. Germany must have reached a similiar conclusion as APDS ammo was not mass produced despite several development programs including APFSDS from smoothbore cannon. I prefer tank cannon able to hit the broad side of a barn so let's cross that option off the list.



The British, on the other hand, have concluded that APDS was a very useful thing, and it was the part of ammo supply for 3 gun calibers of the ww2. The 'regular' AP ammo still be carried in the tank, as it was probably practice in British army. 



> HE capacity is just as important as AP. U.S. Army considered their 76mm HE shell to be poor. Perhaps a better HE shell could have been designed but if that were possible then why didn't it happen historically?



The 76mm HE shell was poor because it was consisted of too much steel and too little HE filler, being tailored to withstand the stresses when it was fired in the gun chamber. US Army can order the cartridge with reduced propellant (= less stress during firing), featuring the bigger/longer HE shell, with thinner walls much greater HE filler. 
Why did it not happened? Well, it took some arms twisting to get the 76mm into Sherman, and 90mm was seen as the immediate future, so they thought why bother? Also, the HE and AP shells with almost the same ballistic properties could use the same sights - not the case when one is, say, 15 lbs, another is 10 lbs.



> German 7.5cm/48 cannon has a good HE shell and decent AP performance in a relatively lightweight and inexpensive package. That's why it's my first choice for a WWII era tank / AT cannon.



It is easy to like that gun.



> British 77mm/50 cannon should work if Britain develops an effective HE shell for the weapon. Or else they could simply copy a captured German KwK40 cannon. Either way they need to get moving. British Sherman tanks should receive the upgrade before the end of 1943.



By the end of 1943, the British have 17pdr in production for a year or so. Even with the APCBC ammo it can kill the Tiger under 1,5 km. The 75mm HV should allow for easier installation and greater ammo count, however. The 77mm HV was a later gun, 75mm HV and 17 pdr being earlier ones.


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## fastmongrel (May 3, 2013)

davebender said:


> WWII era APDS ammo was inaccurate to the point where a 1944 U.S. Army test concluded standard AP was overall superior. Germany must have reached a similiar conclusion as APDS ammo was not mass produced despite several development programs including APFSDS from smoothbore cannon. I prefer tank cannon able to hit the broad side of a barn so let's cross that option off the list.



6pdr and 77mm firing the same design as the 17pdr seemed to have no problems with APDS so it must have been a problem with compatability, rifling twist or chamber dimensions possibly



> HE capacity is just as important as AP.


In a tank HE is more important than AP a tanks job is infantry support 1st and tank fighting 2nd



> German 7.5cm/48 cannon has a good HE shell and decent AP performance in a relatively lightweight and inexpensive package. That's why it's my first choice for a WWII era tank / AT cannon.



Agreed excellent weapon probably the best all round tank gun of the war



> British 77mm/50 cannon should work if Britain develops an effective HE shell for the weapon.



An improved 76.2mm HE shell was available from about Sept 44



> Or else they could simply copy a captured German KwK40 cannon.



Copying a weapon built using metric measurements, different forging techniques and different steels isnt as easy as you think


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## Shortround6 (May 3, 2013)

davebender said:


> WWII era APDS ammo was inaccurate to the point where a 1944 U.S. Army test concluded standard AP was overall superior. Germany must have reached a similiar conclusion as APDS ammo was not mass produced despite several development programs including APFSDS from smoothbore cannon. I prefer tank cannon able to hit the broad side of a barn so let's cross that option off the list.



There was a bad batch of 17pdr APDS that got tested that seems to be widely quoted but it was not truly representative of the accuracy of APDS ammo. It may have been worse than regular AP ammo but it certainly able to hit tanks at combat ranges let alone barns. German's "_must_ have reached a similar conclusion" is bogus. Germans had stopped production of APCR because of a shortage of tungsten. However well APDS may work or not work for long range artillery or AA use trying to use steel cores in APDS shot is near useless. They shatter on impact on armor anywhere near their theoretical penetration limit.



davebender said:


> HE capacity is just as important as AP. U.S. Army considered their 76mm HE shell to be poor. Perhaps a better HE shell could have been designed but if that were possible then why didn't it happen historically?



The HE shell was a left over AA shell. Tank armament is one area where the US had their heads up their butts. They wanted a shell with the same ballistics as the AP shell to simplify gunnery and training. High velocity HE shells means thick walls and low HE and or VERY good steel for the shell body. 



davebender said:


> German 7.5cm/48 cannon has a good HE shell and decent AP performance in a relatively lightweight and inexpensive package. That's why it's my first choice for a WWII era tank / AT cannon.



A good choice but it got the HE capability by dropping the MV of the HE round to about 550 M/S, Less than a Sherman 75mm. No _magic_ or German superiority, just a willingness to trade a bit of difficulty to use ( which _can_ be solved with training) for a more effective overall system. 



davebender said:


> British 77mm/50 cannon should work if Britain develops an effective HE shell for the weapon. Or else they could simply copy a captured German KwK40 cannon. Either way they need to get moving. British Sherman tanks should receive the upgrade before the end of 1943.



British need to adopt a shell with a much lower velocity than the AP round and/or make the shell out of better steel. If they copy the German KwK40 cannon and insist on make the HE round out of 19 ton steel and firing it at 750-790 M/S they will gain NOTHING over the guns they did use.


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## yulzari (May 3, 2013)

davebender said:


> Britain received 17,000 sherman tanks. It's reliable and has decent cross country performance.
> 
> 7.5cm/48 KwK 40 cannon fit into turret of 18 ton (original weight) Panzer IV. A similiar British made cannon should fit into larger Sherman turret without difficulty.
> 
> ...



Not into the 1950s. These were US tanks on loan and had to be given back after the war.


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## vinnye (May 3, 2013)

By the end of the war, Britain was procing better tanks than the Sherman. Not in the same numbers but I would rather have been in a Centurion than a Sherman.


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## davebender (May 3, 2013)

I would rather be in a Tiger then a Panzer III. Such considerations miss the point that heavy tanks cost a lot of money.

Sherman tanks were free (for all practical purposes). All Britain must do is build a better gun that will easily fit in turret (i.e. not 17 pounder) and some additional frontal armor. Now they've got large numbers of an adequate MBT for no development costs (except main gun) and perhaps 20% of Centurion production cost.


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## merlin (May 4, 2013)

It's interesting the testing of the Soviet T-34 KV-1 tanks. Though there seems to be some difference of opinion whether the examples used were of the battlefield and therefore 'worn' or off the production line therefore poor quality equipment!?
I wonder if their design, influenced the sloped armour on the Centurion!

As to the Comet - seems to me that it's design could be brought forward from July '43.
- Enigma traffic could have decoded the consternation felt by German units when they encountered the T-34 KV-1, at first the result would have been wry amusement, but later decodes could relate to German responses.
- intel from occupied Europe about new German large heavy tanks.
- encounters with the upgrades of the Panzer IV Tiger in Africa should have added more urgency than OTL.

So preliminary studies could have been done earlier, the Challenger design was drawn up in 1942 - why not the Comet.

If OTL deliveries start Sept '44, after testing in Feb '44. So IMHO plausible shave a month or three from the Feb to Sept., and bring design process to start late '42, which gives deliveries - with luck - a year earlier than OTL.

Can anyone stretch earlier than that?


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## vinnye (May 4, 2013)

The large numbers of Sherman that Britain had were Lend Lease were they not?
So at the end of the war, they would need to be handed back to the US.
So for Britain to have a credible tank post war - it was necessary for us to design and build it ourselves.


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