Sir John Valentine Carden survives.

I've been consistently trying not to 'wank' the British, trying to make changes that without all the panics might have happened within a different timeframe. When the Grant's 75mm appeared in the Middle East, all of a sudden the cry was for dual purpose, but before that it was 6-pdrs at all costs because the 2-pdr was struggling against the German face-hardened armour. Here the need for a dual purpose purpose is a bit ahead of time, as is the 6-pdr. The follow on, which OTL becomes the Vickers 77mm HV started life as a 75mm. I'm trying to work within the situation that I imagine that Cardin et al are working from. Yes, in retrospect would the 3-inch, 76.2mm gun have been the better choice, probably, but from my point of view, do we really have to make all the right decisions all the time?
The French were using the 75mm on the Char B1, the short 75mm on the captured Pz IV gave some clues about ammo types, and the Americans have gone with a 75mm on the Lee/Grant. While it isn't a common British gun, it is a gun that Vickers have experience of, and is not currently being used for anything else. Will the OTL change make it become the 77mm HV? That is entirely possible, but at this point the Pz III and IV need the 6-pdr, which the Valiant II will give. By 1943-44, the arrival of the Pz V and VI will make the British think about something more powerful, but the current 75mm HV does what Carden wants. It gives better penetration than the 6-pdr and has a good HE, which without the benefit of hindsight, seems a reasonable route to take.
Not to drag this on too long, but while I was in favour of a 3"/76.2mm gun, I think Allans approach is perfectly valid. Vickers are designing a gun which is good enough now (in fact probably better than the M2/M3 at this point?) which will be a better AP gun than those already available and with a substantially better HE capability. And I still think that with an improved charge and with shells following the APC-APCBC-APCR-APDS route, probably enough to see out the war.

I do wonder whether this might encourage the US Army to follow a similar path for their 75mm gun - see this - - for an opinion on possible 75mm HVAP shells.
 
yeah i also think that the author followed the logic of the point of change wich has been mostly centered around vickers being better used than in otl thanks to the person surviving that aircrash and the base of the gun is based on the finnish export order since it is actually around and it only would need modifing . Altough i did find the thought of downzising it abit strange but nothing super duperunrealistic . People are trying introduce way too much hindsight and ideal solutions .
 
yeah i also think that the author followed the logic of the point of change wich has been mostly centered around vickers being better used than in otl thanks to the person surviving that aircrash and the base of the gun is based on the finnish export order since it is actually around and it only would need modifing . Altough i did find the thought of downzising it abit strange but nothing super duperunrealistic . People are trying introduce way too much hindsight and ideal solutions .
Yes

What Vickers will deliver is a tank-gun combination better than the Sherman and delivered around the same time. Which is of more use than an even better tank a year or two later.

The Comet or Centurion equivalent should be ready for 1944. With a 17pr or 77mm but not a 32pr. Or, is a 20pr feasible in 1945 if not 1944?
 
Yes

What Vickers will deliver is a tank-gun combination better than the Sherman and delivered around the same time. Which is of more use than an even better tank a year or two later.

The Comet or Centurion equivalent should be ready for 1944. With a 17pr or 77mm but not a 32pr. Or, is a 20pr feasible in 1945 if not 1944?
The Victor Mk. 1 will carry the 75mm, but I'd expect the Mk.2 to carry the 17-pounder/77mm, once the Royal Artillery has enough in hand, and the process of fitting it in the tank has been sorted.
 
victor will be like the comet equilevant more or less is what i got from the story and comments but earlier and in bigger numbers and its successor probably again name starting with a V i guess instead of the centurion should be available in small numbers for the invasion and maybe after for specilized units or tank brigade or two i guess probably.

Wasnt the centurions gun 84mm , dont know what it is pounds but i think it might be 20 or 24 pounder . Hell considering 25 pounds to get abit more simplified logistics is a thing a to consider for the successor tank to be honest . Altough i still advocate for a infantry tank wich is mainly attached to each infantry divison to make them abit better attacking wise to be honest ? I know its probably a temporary thing and the centurion equilevant tank will probably replace the role but before that a infantry tank made by non vickers firms for frontline infantry divisons is a thing to consider and be something productive for them to do . It would help in attacking in keeping casualties down hopefully wich is always useful and the same for further infantry carriers than in otl .

The main change for the brits tank production wise will be that it will butterfly away the british shermans and fireflys i think and the americans could build more infantry carriers for the british and send the shermans east maybe ? They could also steal the idea for themselves , i mean infantry carriers . They can also send more to the soviets i guess aswell wich might be helpful .

And the way to afford all this is to downsize bomber command a little bit and the same for the americans i guess . Cause bombers were horrificly expensive . I think it was like one freaking squadron of bombers cost like carrier for the brits money wise or it might be a battleship even ? Dont remember exactly but it was horrificly costly and rather useless before 1943 asfar i can tell and started to be war changing thing in 44 but that also consided with the invasion so who knows how much it mattered altough the fuel shortages were one of the main reasons germans lost so badly at the end of the war .
 
Last edited:
The Victor Mk. 1 will carry the 75mm, but I'd expect the Mk.2 to carry the 17-pounder/77mm, once the Royal Artillery has enough in hand, and the process of fitting it in the tank has been sorted.
Let's hope so, the 3"/77mm would be an excellent gun for D-Day and beyond. Maybe a Tank Destroyer version with 17pr (32pr probably too heavy?) would be useful as a longer range "sniper" to deal with Tigers and Panthers. But as i understand it dug in Anti-tank guns were the more usual problem and the 77mm will be adequate for them. And to deal with all German tamks at typical combat ranges.
 
victor will be like the comet equilevant more or less is what i got from the story and comments but earlier and in bigger numbers and its successor probably again name starting with a V i guess instead of the centurion should be available in small numbers for the invasion and maybe after for specilized units or tank brigade or two i guess probably.

Wasnt the centurions gun 84mm , dont know what it is pounds but i think it might be 20 or 24 pounder . Hell considering 25 pounds to get abit more simplified logistics is a thing a to consider for the successor tank to be honest . Altough i still advocate for a infantry tank wich is mainly attached to each infantry divison to make them abit better attacking wise to be honest ? I know its probably a temporary thing and the centurion equilevant tank will probably replace the role but before that a infantry tank made by non vickers firms for frontline infantry divisons is a thing to consider and be something productive for them to do . It would help in attacking in keeping casualties down hopefully wich is always useful and the same for further infantry carriers than in otl .

The main change for the brits tank production wise will be that it will butterfly away the british shermans and fireflys i think and the americans could build more infantry carriers for the british and send the shermans east maybe ? They could also steal the idea for themselves , i mean infantry carriers . They can also send more to the soviets i guess aswell wich might be helpful .

And the way to afford all this is to downsize bomber command a little bit and the same for the americans i guess . Cause bombers were horrificly expensive . I think it was like one freaking squadron of bombers cost like carrier for the brits money wise or it might be a battleship even ? Dont remember exactly but it was horrificly costly and rather useless before 1943 asfar i can tell and started to be war changing thing in 44 but that also consided with the invasion so who knows how much it mattered altough the fuel shortages were one of the main reasons germans lost so badly at the end of the war .
Early centurion model mk1&2s used 17 pounder (76.2 mm) then came mk 3 in20 pounder (84mm) in 1947. Mk5/2 and later used L7 (105mm) post 1959
 
victor will be like the comet equilevant more or less is what i got from the story and comments but earlier and in bigger numbers and its successor probably again name starting with a V i guess instead of the centurion should be available in small numbers for the invasion and maybe after for specilized units or tank brigade or two i guess probably.
The Victor will indeed by the Comet equivalent, but earlier, more numerous, and probably better, depending in Carden can sell them on not having the hull MG.

Wasnt the centurions gun 84mm , dont know what it is pounds but i think it might be 20 or 24 pounder . Hell considering 25 pounds to get abit more simplified logistics is a thing a to consider for the successor tank to be honest . Altough i still advocate for a infantry tank wich is mainly attached to each infantry divison to make them abit better attacking wise to be honest ? I know its probably a temporary thing and the centurion equilevant tank will probably replace the role but before that a infantry tank made by non vickers firms for frontline infantry divisons is a thing to consider and be something productive for them to do . It would help in attacking in keeping casualties down hopefully wich is always useful and the same for further infantry carriers than in otl .
Depends on the version. the Mk 1 and Mk 2 used the 17-pounder, the Mk 3, Mk 4 and Mk 5/1, and then to the L7 from the Mk 5/2. The 25-pounder is a howitzer, so not a great tank gun.

The main change for the brits tank production wise will be that it will butterfly away the british shermans and fireflys i think and the americans could build more infantry carriers for the british and send the shermans east maybe ? They could also steal the idea for themselves , i mean infantry carriers . They can also send more to the soviets i guess aswell wich might be helpful .
Not all of the Shermans I think, but it will significantly reduce the number in service.

And the way to afford all this is to downsize bomber command a little bit and the same for the americans i guess . Cause bombers were horrificly expensive . I think it was like one freaking squadron of bombers cost like carrier for the brits money wise or it might be a battleship even ? Dont remember exactly but it was horrificly costly and rather useless before 1943 asfar i can tell and started to be war changing thing in 44 but that also consided with the invasion so who knows how much it mattered altough the fuel shortages were one of the main reasons germans lost so badly at the end of the war .
Well you're going stright from the Valiant to the Victor, so you're skipping the costs of the OTL Cavalier, Cromwell and Challenger tanks, which will save a fair bit.
 
victor will be like the comet equilevant more or less is what i got from the story and comments but earlier and in bigger numbers and its successor probably again name starting with a V i guess instead of the centurion should be available in small numbers for the invasion and maybe after for specilized units or tank brigade or two i guess probably.

Wasnt the centurions gun 84mm , dont know what it is pounds but i think it might be 20 or 24 pounder . Hell considering 25 pounds to get abit more simplified logistics is a thing a to consider for the successor tank to be honest . Altough i still advocate for a infantry tank wich is mainly attached to each infantry divison to make them abit better attacking wise to be honest ? I know its probably a temporary thing and the centurion equilevant tank will probably replace the role but before that a infantry tank made by non vickers firms for frontline infantry divisons is a thing to consider and be something productive for them to do . It would help in attacking in keeping casualties down hopefully wich is always useful and the same for further infantry carriers than in otl .

The main change for the brits tank production wise will be that it will butterfly away the british shermans and fireflys i think and the americans could build more infantry carriers for the british and send the shermans east maybe ? They could also steal the idea for themselves , i mean infantry carriers . They can also send more to the soviets i guess aswell wich might be helpful .

And the way to afford all this is to downsize bomber command a little bit and the same for the americans i guess . Cause bombers were horrificly expensive . I think it was like one freaking squadron of bombers cost like carrier for the brits money wise or it might be a battleship even ? Dont remember exactly but it was horrificly costly and rather useless before 1943 asfar i can tell and started to be war changing thing in 44 but that also consided with the invasion so who knows how much it mattered altough the fuel shortages were one of the main reasons germans lost so badly at the end of the war .
Good points.

I cant recollect if the Victor is to be Comet sized or more like a Cromwell with a larger turret. Whichever, it will be slower and better armoured. I think the initial 75mm gun for the Victor Mk1 sounds a bit less powerful than the 77mm but a Mk2 could have a more powerful gun.

AIUI the Centurion 20pr was 83.4mm, the same calibre as the 25pr field gun/howitzer but obviously longer and different ammunition. It probably isn't even a gleam in a designer's eyes ATM.

I think it was a wing of 2-3 bomber squadrons that cost the same to build an operate as a battleship. A slower build up of Bomber Command would help release resources not just for the Army but also the Battle of the Atlantic. Which is more important in both OTL and this TL.

But that decision is probably outside the scope of the butterflies released by our author.
 
1 - With the Vickers 75mm HV in production and the potential to improve/redesign this to a 77mm equivalent, I doubt there will be any need for 17 pounders in tanks - leave them to the gunners, with perhaps an improved Archer type TD.

2 - No doubt there will be plans for a Victor replacement and gun to suit, but even with the OTL problems with UK tank design and production, Centurions weren't in full production until November 45 (per Wiki). What drivers to advance this ITTL with better tanks in operational use...?
 
On top of the better guns we are probably also seeing increased technical reliability since Carden probably acts as a reality check for some of the crazier ideas as well as being one of the most experienced designers in the UK right now as well as only a few types of tank are being built right now it means the lines and the people who work on them are getting more experienced at turning out the tanks in question. You will also have the feedback from the front which will help as well.

Someone remind me have we had any updates on the Tog since it first came up? I mean right now its proving to be a waste of resources for the UK so I assume some are lobbying it to be scrapped.
 
Last edited:
1 - With the Vickers 75mm HV in production and the potential to improve/redesign this to a 77mm equivalent, I doubt there will be any need for 17 pounders in tanks - leave them to the gunners, with perhaps an improved Archer type TD.

2 - No doubt there will be plans for a Victor replacement and gun to suit, but even with the OTL problems with UK tank design and production, Centurions weren't in full production until November 45 (per Wiki). What drivers to advance this ITTL with better tanks in operational use...?
The `Mega` Cats of the germans of course.... Much of the the debate is from the allied point of view, but as soon the Victor is on the battlefield, the Germans have got to react.
 
The `Mega` Cats of the germans of course.... Much of the the debate is from the allied point of view, but as soon the Victor is on the battlefield, the Germans have got to react.
It's probably going to see service about the same time the Panther does. Of course, the question remains of where the Victor and Panther will first meet. If it's not Italy it's probably going to be France. That would panic the Germans a bit I suspect, the Allies having a tank which is qualitatively almost a match for the Panther.
 
Last edited:
Well, if you want a more powerful tank gun, there is always the RN 4" AA gun, currently in production.
35lb shell at 2,660 fps.
Wouldn't do a Tiger any good at all...
OK, it does weight 2 tons...
 
So heres the thing.
The 75mm Vickers have produced ITTL is basically a logisticians nightmare. It is essentially the same gun as the 3 inch 16cwt of OTL but in a different calibre. That was made by converting 3 inch 20cwt AA guns into AT guns. That work will have likely finished by this point in TL from what I can tell. This was also the gun put into the Churchill gun carrier.

The 75mm fires a 75mm projectile at 2550ft/s
The 3 inch fired a 12.5lb projectile at 2500ft/s.

The reason the 3 inch fires at that velocity is because that is what the gun was designed to handle. They are pushing 25 years old by this point so you can't really push them too much. Barrel life was an issue with the 2500ft/s rounds already. That was why they moved to a 16lb round for the 3 inch 20cwt, to preserve Barrel life.

If you are making a brand new gun then more performance than a 25 year old AA would likely be required. If not and you are happy with the performance why not just make use of the 3 inch ammo but in a more modern and lighter gun?
 
According to - https://www.iwm.org.uk/history/brit...d-effective-tanks-during-the-second-world-war

The final significant development in Britain's wartime tank story was the A41 Centurion. It began as an idea in 1942 for a tank that combined several battlefield roles. The desert war had shown that pure 'cavalry-style' tank versus tank combat predicted by the pre-war visionaries rarely occurred. Similarly, the infantry tank concept – believed in 1939 to be the most important – was too restrictive on a modern battlefield. Experience had taught instead that the main function of the tank was to act as mobile fire support in both attack and defence. With this in mind the War Office and the Department of Tank Design looked towards a 'universal tank' that could fulfil all these functions. By 1943, the old width and weight restrictions had been abandoned, and so designers had a free rein. The new tank was to have good cross country performance, mount a 17-pdr gun and be protected by thick, sloped armour able to resist the German 88mm gun. AEC was authorised to begin work in July 1943, but the war ended before it was finished.

This is with Panthers, Tigers and late Pzkpfw IVs doing pretty well against Cromwells, Shermans and Churchills.
 
I am getting a little confused!
The WW1 British 3" AA gun fired either a 12.5lb round at 2600ft/s or a 16lb round at 2000ft/s
whereas the Vickers 1931, 75 mm AA gun fire a 14lb 5oz round at 2500ft/s .
The Vickers round is 495mm R and the 3" round is 420mm R.
Vickers have the tooling to make both!
In 1940 either gun will kill any tank it faces. It does not matter which is produced it will work. The 3" will be easier on the logistics train as it is already in use and the American's are not yet supplying 75mm ammunition in Signiant quantities to the British ITL.
Personally which is used ITTL is a very mute point, as long at it works and is available when needed.

To a Panzer crew being hit by one of these are they really going to be bothered whether it's 75mm or 3"!!!
 
I am getting a little confused!
The WW1 British 3" AA gun fired either a 12.5lb round at 2600ft/s or a 16lb round at 2000ft/s
whereas the Vickers 1931, 75 mm AA gun fire a 14lb 5oz round at 2500ft/s .
The Vickers round is 495mm R and the 3" round is 420mm R.
Vickers have the tooling to make both!
In 1940 either gun will kill any tank it faces. It does not matter which is produced it will work. The 3" will be easier on the logistics train as it is already in use and the American's are not yet supplying 75mm ammunition in Signiant quantities to the British ITL.
Personally which is used ITTL is a very mute point, as long at it works and is available when needed.

To a Panzer crew being hit by one of these are they really going to be bothered whether it's 75mm or 3"!!!
So
The WW1 3inch 20cwt fired either a
12.5lb projectile at 2550ft/s or a
16lb projectile at 2000ft/s

This gun is still in service with Britain. The army has a couple hundred and most were emergency converted to AT guns. This made them a little lighter but they fired the normal 12.5lb round at the same velocity. This is all using a 420mm case as you say but it is a fat case. The rim diameter is 116mm so the case is short and squat but has a high capacity.

The vickers 75mm is as you say a 495mm long case but pretty much straight walled. Has a bit less internal volume for propellant IIRC. I will happily be corrected on that though and I don't think there is much in in either way.

Vickers ITTL started out with the full 75mm set but was asked to change to the case from the 3 inch 20cwt. That was because a short fat case is easier to manoeuvre in a turret than a long thin case.
The end result however is a 12.5lb 75mm projectile at 2550ft/s. The same as the already being produced 3" AT shell.

I don't understand why the decision was not made to just use the 3" round if they are happy with that performance. They can keep using the same ammo production at that point.
 
With regards to the 75mm and not 76.2mm the answer could be as simple as Vickers was already working on it and simply ran with what they had - an off the shelf design so to speak

And as for logistics and production - a new round and gun production line would be required regardless of it being 75mm or 76.2mm and therefore "new production" not existing production - so it does not matter which was chosen
 
Top