M3 Grant and M4 Sherman Family of Vehicles

[tomo pauk]

...
OK, let me put it this way - the British Mathilda II had a 2 Pdr gun.  It was an "I" or Infantry tank - designed to be heavily armoured and to accompany infantry in the assault and facilitate their capture of their objectives.  It carried no HE until 1943 (in Australian service, the British never carried 2 Pdr HE in their Mathildas).

To us, it appears inexplicable that someone would not provide a HE round to a tank who's sole point was to support infantry but British doctrine was that the role of the Infantry tank was to use its MGs to support the infantry and its main gun to protect them from other tanks!  To the British Army it made perfect sense as it was the Artillery which was to destroy or neutralise enemy strong points, not the Armoured Corps.  This doctrine was developed on the basis of WWI experience, where Artillery was King.   It wasn't until battle experience in the Desert showed how wrong this was that thoughts turned to heavier weapons.   Initially they tried to mount two weapons in the one turret.  A 2 Pdr to shoot at tanks and a 3 in Howitzer to shoot at infantry.  However, they encountered problems.  In the Churchill they mounted a 3 in How. in the hull and a 2 Pdr in the turret but  on the basis of experience with first M3 Mediums and them M4 Mediums with a 75mm gun which could do both, opted to adopt that calibre.

I agree with what you've said here; British tank doctrine did have it's flaws Basically, Brits were lacking a good pre-war HE-thrower akin of what Continental powers had.

The American Army decided that their tanks should be able to engage both enemy armour and infantry.

That sentence is in contrast with another sentences (post #174 in this thread), that got all this 3-page discussion going:
US Armoured Doctrine had it that the job of tank hunting was that of the Tank Destroyers.  Tanks were to support infantry.

While they could engage tanks their primary role was that of infantry support.  They provided them with, initially a 37mm gun and when they realise that was inadequate a 75mm gun.  The M3 was only intended to be a stop gap.  They realised that mounting the main gun in the hull was silly but felt they needed to field a medium tank quickly while they developed a proper, turret mounted weapon.

Well put.

The Ordnance Board (who designed and built the tanks) was throughout WWII fighting a battle with the Army over tank armament.  The Army wanted vehicles which would fit their doctrine, the Ordnance Board was pushing for bigger, heavier vehicles and guns.  The Army kept knocking them back.  Witness the problems over getting the M26 Pershing adopted.   It was basically ready in mid-1944 yet it took over six months to convince the Army to take them!

At least having M4 with 3in from day one would've been cool, but it didn't happen...

As for small caliber guns being standard, France, Germany and USSR (= main continental powers) designed & fielded tanks with 75mm class gun well prior mid 1940 (Char B1, Pz-IV, BT-5A/7A). That points out that small caliber guns (even the Soviet 45mm) were way underpowered for infantry support.

In two out of the three cases you name, the 75mm "class gun" was mounted on a heavy tank.  Only the Soviets were trying to mount it on a smaller vehicle. 

Pz-IV was as heavy as Pz-III almost all the time (while lighter than Matilda II by 8-10 tons), so the adjective 'heavy' is applicable to the nomenclature at the time (1935-36?) Guderian called for such a tank, not to the real weight.

Its also interesting to note that in all three, the role was that of effectively an "artillery tank" - designed to engage targets with HE, not AP (although AP was provided).

But of course they engaged the targets with HE (plus 47mm, for Char B1) - proving that engaging 'soft' targets with pop guns was ineffective.

In all three, the main, medium tank gun remained the 37-45mm gun.  Thinking on that didn't change until experience showed the need for a larger calibre.

That leads us at 3in mounted at M3 medium: it can engage 'soft' targets decently (or even better, if the round with bigger HE shell & smaller charge is produced), while offering much better AP performance than both 37mm & 75mm. Plus, it reduces tanks height for some 3 ft; the weight reduction can be employed to bolster the armor protection; crew can be reduced to 5 men. Feasible before the M4, or M4 with in.

[dy031101]

That sentence is in contrast with another sentences (post #174 in this thread), that got all this 3-page discussion going:
US Armoured Doctrine had it that the job of tank hunting was that of the Tank Destroyers.  Tanks were to support infantry.

Medium tanks has always been deemed as equally-applicable to both offense and defense, and it's hard to imagine that the term "infantry support" did not take into account hostile medium tanks.

[tomo pauk]

Exactly; hence my disagreement with "TD's hunt enemy tanks, while own tanks support infantry" thesis

[dy031101]

Exactly; hence my disagreement with "TD's hunt enemy tanks, while own tanks support infantry" thesis

In some way it fits: the 75mm gun on the M3 and M4 Mediums is both an effective HE thrower and a good-enough anti-medium-tank gun.  The doctrine didn't call for medium tanks to do better than that.

The kind of target that was strictly to be left to tank destroyers are heavy tanks, whose value as a defensive weapon was only truly recognized during the Allied counterattack in Europe (and even then the Germans used heavy tanks defensively because they as a whole were on defensive and therefore in no condition to do Blitzkrieg anymore); before then heavy tanks had mostly been regarded as an offensive weapon.  Of course these settings which the counterattacking Allies laboured under ended up definitively exposing the weakness of the US doctrine.

[rickshaw]

I agree with what you've said here; British tank doctrine did have it's flaws Basically, Brits were lacking a good pre-war HE-thrower akin of what Continental powers had.

Its a bit more complex than that.  They had a "good pre-war HE-thrower" in the 2 Pdr.  Their problem was doctrinal - tanks destroyed tanks, they did not need HE ammunition.  A HE round was developed and issued to the artillery, not to tanks.   The Australians developed a HE round independently in late 1942, trialled it in 1943 and fielded it in late 1943.  It was quite effective and that was why the Mathilda II remained in Australian service long after it had been sent to the scrapyard in other armies.   They also had the 3in Howitzer, which was quite a good HE round but it lacked an AP round and its muzzle velocity was too low to be useful in the role.

The American Army decided that their tanks should be able to engage both enemy armour and infantry.

That sentence is in contrast with another sentences (post #174 in this thread), that got all this 3-page discussion going:
US Armoured Doctrine had it that the job of tank hunting was that of the Tank Destroyers.  Tanks were to support infantry.

I think you're missing the operative word there - "hunting".   Tank Destroyers purposefully hunted tanks, their roll was destruction of armoured vehicles.  Tanks were capable of destroying tanks if they encountered them but did not purposefully go out of their way to find them.  Their roll was infantry support.  Does that make it clearer for you?

In reality, what was required was a "universal tank" - one which could hunt and destroy armour and also support infantry.  Its need was not so much physical as doctrinal.

At least having M4 with 3in from day one would've been cool, but it didn't happen...

It couldn't happen because the need was not seen at the time because of doctrinal ideas about the role of the tank.

Pz-IV was as heavy as Pz-III almost all the time (while lighter than Matilda II by 8-10 tons), so the adjective 'heavy' is applicable to the nomenclature at the time (1935-36?) Guderian called for such a tank, not to the real weight.

The Mk.IV was considered a "heavy tank" because of the calibre of its weapon and its role as a "breakthrough vehicle".

But of course they engaged the targets with HE (plus 47mm, for Char B1) - proving that engaging 'soft' targets with pop guns was ineffective.

It wasn't ineffective which assumes that it would have no effect.  It was merely less effective.  An anti-tank gun attacked with a HE round from a 47mm gun would require more rounds to knock it out but it could still be knocked out.

That leads us at 3in mounted at M3 medium: it can engage 'soft' targets decently (or even better, if the round with bigger HE shell & smaller charge is produced), while offering much better AP performance than both 37mm & 75mm. Plus, it reduces tanks height for some 3 ft; the weight reduction can be employed to bolster the armor protection; crew can be reduced to 5 men. Feasible before the M4, or M4 with in.

Again, that could only occur in what-if.  In real life a bigger HE round was not designed - indeed it wasn't found until after battle experience that the HE round for the 3in was less effective than the 75mm's.

As to lowering the vehicle height, I am unsure which vehicle you're discussing but I assume you mean the M3 Medium?  Mounting a 3in in place of the 75mm would not reduce the hull height at all.  The same determinant of hull height - the height of an average crewman was still present.  Even more so as the loader would be expected to handle a larger shell in the same space that he was to handle the smaller 75mm rounds.   As designing a fully rotating turret which could absorb the recoil of the 75mm took appreciably longer than was expected, I'd suggest designing one which could absorb the recoil of the 3in would present an even greater problem and hence longer yet again.

What you must understand is that the steps taken in armour and armament were, for the most part, necessary as part of a curve in both learning and implementing new developments which resulted from battlefield experience.   What I more and more appreciate the more I read about the development of military technology, particularly in wartime is how dependent and reactive each development is to the circumstances that were experienced on the battlefield and how fast the various combatants were able to react to them.

[tomo pauk]

Its a bit more complex than that.  They had a "good pre-war HE-thrower" in the 2 Pdr.

By what standards 2pdr is considered a good HE-thrower (even after HE is issued to tanks - so not a 'pre-war')?

Their problem was doctrinal - tanks destroyed tanks, they did not need HE ammunition.  A HE round was developed and issued to the artillery, not to tanks.   The Australians developed a HE round independently in late 1942, trialled it in 1943 and fielded it in late 1943.  It was quite effective and that was why the Mathilda II remained in Australian service long after it had been sent to the scrapyard in other armies.   They also had the 3in Howitzer, which was quite a good HE round but it lacked an AP round and its muzzle velocity was too low to be useful in the role.

I've agreed previously that British tank doctrine was lacking in some aspects prior mid-WW2
You will allow me to disagree about the qualities of 2pdr HE shell - I'd say it was decent (like other 37-47mm HE shells), yet falling way behind of 3in stuff. And it doesn't fit in the 'pre-war' category.

I think you're missing the operative word there - "hunting".   Tank Destroyers purposefully hunted tanks, their roll was destruction of armoured vehicles.  Tanks were capable of destroying tanks if they encountered them but did not purposefully go out of their way to find them.  Their roll was infantry support.  Does that make it clearer for you?

If the 'infantry support' role includes engaging all ground targets that want to kill own infantry, than I'd say mounting a gun as big as hull can wield without problems is a good thing. Hope I'm clear about that.

[about M4 produced with 3in from day one]
It couldn't happen because the need was not seen at the time because of doctrinal ideas about the role of the tank.

Covered above.

The Mk.IV was considered a "heavy tank" because of the calibre of its weapon and its role as a "breakthrough vehicle"

Agreed. Yet, that sentence is in contrast with:
In two out of the three cases you name, the 75mm "class gun" was mounted on a heavy tank.  Only the Soviets were trying to mount it on a smaller vehicle.

It wasn't ineffective which assumes that it would have no effect.  It was merely less effective.  An anti-tank gun attacked with a HE round from a 47mm gun would require more rounds to knock it out but it could still be knocked out.

Indeed. It also means that subject AT gun would've have fired more rounds, hence more chances of knocking out the tank that was not hitting it bulls eye.

As to lowering the vehicle height, I am unsure which vehicle you're discussing but I assume you mean the M3 Medium?  Mounting a 3in in place of the 75mm would not reduce the hull height at all.  The same determinant of hull height - the height of an average crewman was still present.  Even more so as the loader would be expected to handle a larger shell in the same space that he was to handle the smaller 75mm rounds.   As designing a fully rotating turret which could absorb the recoil of the 75mm took appreciably longer than was expected, I'd suggest designing one which could absorb the recoil of the 3in would present an even greater problem and hence longer yet again

I've proposed deletion of the turret, along with 3in installed in lieu of 75mm, in the same post

What you must understand is that the steps taken in armour and armament were, for the most part, necessary as part of a curve in both learning and implementing new developments which resulted from battlefield experience.   What I more and more appreciate the more I read about the development of military technology, particularly in wartime is how dependent and reactive each development is to the circumstances that were experienced on the battlefield and how fast the various combatants were able to react to them.

That's very true.
I've proposed, in 2011, a modification of a 1940-ish tank. So the curve is pretty level now

[rickshaw]

I've proposed, in 2011, a modification of a 1940-ish tank. So the curve is pretty level now

The question would be - why bother?   There are plenty of later generation tanks available today on the market which are much cheaper to operate and maintain and of course, are much more deadly.      Even just finding the ammunition for it would be fraught with difficulties.  You'd have to start manufacturing it and that again adds to the costs.  Spare parts would be nearly impossible to find in any quantity.  Rebuilding or modifying old, in the case of WWII vintage, ancient AFVs is invariably more expensive than buying a new(ish) one.

[rickshaw]

Its a bit more complex than that.  They had a "good pre-war HE-thrower" in the 2 Pdr.

By what standards 2pdr is considered a good HE-thrower (even after HE is issued to tanks - so not a 'pre-war')?

Well, it always stems back to what you want it to do.  In the case of the 2 Pdr, it was an adequate weapon until about late 1941.  The problem for the British was that because of the exigencies of Dunkirk, they had to keep the 2 Pdr in production longer than they should have, so it served past its use-by-date and unfortunately its that period that it all too often gets judged on, as a tank gun.  In Australian service, the Mathilda was just the right balance between armour, mobility and armament for use in the SWP theatre of operations.  The 2 Pdr was able to penetrate all Japanese medium tanks and its HE round was quite successful in being able to penetrate and destroy Japanese bunkers, even of the dreaded coconut and sand variety.   The Australians equipped their HE round with a base fuse for just that purpose whereas the British HE round had a nose fuse which was better adapted to the destruction of soft-skinned vehicles and AT guns.

I've agreed previously that British tank doctrine was lacking in some aspects prior mid-WW2
You will allow me to disagree about the qualities of 2pdr HE shell - I'd say it was decent (like other 37-47mm HE shells), yet falling way behind of 3in stuff. And it doesn't fit in the 'pre-war' category.

It was decent, yes.  3in though, wasn't available and thats the point I keep making.  You want something that wasn't available.  Sure, you can leap into what-if BUT that would require a complete rethinking of doctrine and procurement policies, well before the date you seem to think it was possible to have the 3in gun in all tanks.

If the 'infantry support' role includes engaging all ground targets that want to kill own infantry, than I'd say mounting a gun as big as hull can wield without problems is a good thing. Hope I'm clear about that.

You are.  Problem is, the US tanks weren't capable of mounting that gun in a rotating turret until mid-1941 when the M4 medium was designed.  It had to be hull mounted, which is why the M3 medium was designed.  So, indeed, US tanks and British tanks and German tanks did mount "a gun as big as the hull can wield without problems" as required by the military authorities at that time.  For most, the gun they felt they needed was in the 37-47mm class.    They didn't use a bigger gun until experience showed it was needed.   Until that experience occurs, the thinking will remain, 37-47mm is adequate enough.

The Mk.IV was considered a "heavy tank" because of the calibre of its weapon and its role as a "breakthrough vehicle"

Agreed. Yet, that sentence is in contrast with:
In two out of the three cases you name, the 75mm "class gun" was mounted on a heavy tank.  Only the Soviets were trying to mount it on a smaller vehicle.

I'm sorry?  I can't see any contrast between the two.  The Mk.IV was called a "heavy tank" because it was used as a "heavy tank" by its users.  I suspect you're using a classification system which is much later and different to the one used when the Mk.IV was introduced.

It wasn't ineffective which assumes that it would have no effect.  It was merely less effective.  An anti-tank gun attacked with a HE round from a 47mm gun would require more rounds to knock it out but it could still be knocked out.

Indeed. It also means that subject AT gun would've have fired more rounds, hence more chances of knocking out the tank that was not hitting it bulls eye.

Yes.  So?   The 47mm was still adequate in the eyes of those who designed and procured the tank which mounted it.  Remember, it was only after experience had shown otherwise that bigger guns would be considered required.

As to lowering the vehicle height, I am unsure which vehicle you're discussing but I assume you mean the M3 Medium?  Mounting a 3in in place of the 75mm would not reduce the hull height at all.  The same determinant of hull height - the height of an average crewman was still present.  Even more so as the loader would be expected to handle a larger shell in the same space that he was to handle the smaller 75mm rounds.   As designing a fully rotating turret which could absorb the recoil of the 75mm took appreciably longer than was expected, I'd suggest designing one which could absorb the recoil of the 3in would present an even greater problem and hence longer yet again

I've proposed deletion of the turret, along with 3in installed in lieu of 75mm, in the same post

OK, so we have a headless 3in equipped M3 Medium.   Essentially what you're after then is an SP gun, right?  Not a tank at all.

What you must understand is that the steps taken in armour and armament were, for the most part, necessary as part of a curve in both learning and implementing new developments which resulted from battlefield experience.   What I more and more appreciate the more I read about the development of military technology, particularly in wartime is how dependent and reactive each development is to the circumstances that were experienced on the battlefield and how fast the various combatants were able to react to them.

That's very true.
I've proposed, in 2011, a modification of a 1940-ish tank. So the curve is pretty level now

OK, is this proposed modification occurring in 2011 or in the 1940s?

[tomo pauk]

I've proposed, in 2011, a modification of a 1940-ish tank. So the curve is pretty level now

The question would be - why bother?   There are plenty of later generation tanks available today on the market which are much cheaper to operate and maintain and of course, are much more deadly.      Even just finding the ammunition for it would be fraught with difficulties.  You'd have to start manufacturing it and that again adds to the costs.  Spare parts would be nearly impossible to find in any quantity.  Rebuilding or modifying old, in the case of WWII vintage, ancient AFVs is invariably more expensive than buying a new(ish) one.

In this forum we can see monoplane Gladiators, Hurricanes with floats, P-40s with ASh-82 etc. My M3 medium with 3in in casemate/sponsoon fits here perfectly.

[tomo pauk]

....
By what standards 2pdr is considered a good HE-thrower (even after HE is issued to tanks - so not a 'pre-war')?

Well, it always stems back to what you want it to do.  In the case of the 2 Pdr, it was an adequate weapon until about late 1941.  The problem for the British was that because of the exigencies of Dunkirk, they had to keep the 2 Pdr in production longer than they should have, so it served past its use-by-date and unfortunately its that period that it all too often gets judged on, as a tank gun.  In Australian service, the Mathilda was just the right balance between armour, mobility and armament for use in the SWP theatre of operations.  The 2 Pdr was able to penetrate all Japanese medium tanks and its HE round was quite successful in being able to penetrate and destroy Japanese bunkers, even of the dreaded coconut and sand variety.   The Australians equipped their HE round with a base fuse for just that purpose whereas the British HE round had a nose fuse which was better adapted to the destruction of soft-skinned vehicles and AT guns.

Can we agree that 2pdr was surpassed by 75-76mm in HE performance by a wide margin?

I've agreed previously that British tank doctrine was lacking in some aspects prior mid-WW2
You will allow me to disagree about the qualities of 2pdr HE shell - I'd say it was decent (like other 37-47mm HE shells), yet falling way behind of 3in stuff. And it doesn't fit in the 'pre-war' category.

It was decent, yes.  3in though, wasn't available and thats the point I keep making.  You want something that wasn't available.  Sure, you can leap into what-if BUT that would require a complete rethinking of doctrine and procurement policies, well before the date you seem to think it was possible to have the 3in gun in all tanks.

Sorry if I was not crystal clear. When saying "3in stuff", I refer to guns of about 3in calibre (75-76,2mm), not the particular British gun. If others were fielding it, while Brits didn't, it was their flaw. You will notice that I've never said 'lets arm every tank with 3in stuff ASAP' - just the tanks capable to operate it.

If the 'infantry support' role includes engaging all ground targets that want to kill own infantry, than I'd say mounting a gun as big as hull can wield without problems is a good thing. Hope I'm clear about that.

You are.  Problem is, the US tanks weren't capable of mounting that gun in a rotating turret until mid-1941 when the M4 medium was designed.  It had to be hull mounted, which is why the M3 medium was designed.  So, indeed, US tanks and British tanks and German tanks did mount "a gun as big as the hull can wield without problems" as required by the military authorities at that time.  For most, the gun they felt they needed was in the 37-47mm class.    They didn't use a bigger gun until experience showed it was needed.   Until that experience occurs, the thinking will remain, 37-47mm is adequate enough.

?? I was talking about re-arming the M3 with 3in in casemate from 1941/42.

The Mk.IV was considered a "heavy tank" because of the calibre of its weapon and its role as a "breakthrough vehicle"

Agreed. Yet, that sentence is in contrast with:
In two out of the three cases you name, the 75mm "class gun" was mounted on a heavy tank.  Only the Soviets were trying to mount it on a smaller vehicle.

I'm sorry?  I can't see any contrast between the two.  The Mk.IV was called a "heavy tank" because it was used as a "heavy tank" by its users.  I suspect you're using a classification system which is much later and different to the one used when the Mk.IV was introduced.

I one sentence, you compare tank's weights (heavy Pz-IV vs. smaller BT), in another you state heavy firepower as reason of putting the Pz-IV in 'heavy' category.

It wasn't ineffective which assumes that it would have no effect.  It was merely less effective.  An anti-tank gun attacked with a HE round from a 47mm gun would require more rounds to knock it out but it could still be knocked out.

Indeed. It also means that subject AT gun would've have fired more rounds, hence more chances of knocking out the tank that was not hitting it bulls eye.

Yes.  So?   The 47mm was still adequate in the eyes of those who designed and procured the tank which mounted it.  Remember, it was only after experience had shown otherwise that bigger guns would be considered required.

We all know what brass wanted, what was required, and what vehicles were fielded. I propose something else, in an appropriate forum. If it's okay with you, very well. If not, very well again.

OK, so we have a headless 3in equipped M3 Medium.   Essentially what you're after then is an SP gun, right?  Not a tank at all.

So what?

OK, is this proposed modification occurring in 2011 or in the 1940s?

Late 1941-early 1942.

[Maverick]

Tomo, if I may.

If a 'modifed' M3 were to be built, I doubt any on here would say anything but positives about it.  However, you're suggesting that it is an improvement than can be made within the timeframe they were built, but using hindsight and knowing the lessons learnt before they are given. 

A 'different model' is fine and dandy, but then to justify it with logic and/or knowledge that benefits from things that those within that timeframe had no access to is unreasonable and goes beyond 'plausible' into pure fantasy. 

Many on here like to see a 'plausible' take on whifs, especially if there is some detailed explanation associated with the conversion as you've suggested.  If it were merely built (or drawn) who's to complain?  Perhaps minor notes but beyond that, nothing much.  But put in a complex, detailed background and people will ask for much more 'reality' and a more realistic take on the modifications possible (using the knowledge that those building it would have had and not something that can be researched in the future).

I hope this is helpful in explaining why the questions are asked here,

Mav

[rickshaw]

Tomo, if I may.

If a 'modifed' M3 were to be built, I doubt any on here would say anything but positives about it.  However, you're suggesting that it is an improvement than can be made within the timeframe they were built, but using hindsight and knowing the lessons learnt before they are given. 

A 'different model' is fine and dandy, but then to justify it with logic and/or knowledge that benefits from things that those within that timeframe had no access to is unreasonable and goes beyond 'plausible' into pure fantasy. 

Many on here like to see a 'plausible' take on whifs, especially if there is some detailed explanation associated with the conversion as you've suggested.  If it were merely built (or drawn) who's to complain?  Perhaps minor notes but beyond that, nothing much.  But put in a complex, detailed background and people will ask for much more 'reality' and a more realistic take on the modifications possible (using the knowledge that those building it would have had and not something that can be researched in the future).

I hope this is helpful in explaining why the questions are asked here,

Mav

Mav, I fear that I have been led down a long, dark winding path on this one.  Tomo wants to do a "what-if' of the M3.  He is welcome to.  However, he has asked questions as to "why didn't they...?" And I have attempted to answer them.   The reason ultimately as to "why didn't they...?"  Was because they didn't.

The Allies didn't because they didn't have the experience which showed their previous decisions were wrong and when they got that experience they sought to correct their previous misconceptions and ultimately they played "catch-up" continuously, finding that their developments invariably lagged behind that of their main enemy.  Throughout that time they were dogged by doctrinal theories which proved inadequate in the face of the enemy and which also hampered their efforts to produce a tank which would beat the enemy.  Simple really and that answers all such questions.

Tomo, if you want to produce a "what-if" M3 Medium, go right ahead and I will praise it to the roof tops.  Please though, don't ask questions and then complain when the answers don't satisfy you because you aren't interested in them but rather interested in your own counter-factual history.

I now bow out of this thread.

[dy031101]

Mav, I fear that I have been led down a long, dark winding path on this one.  Tomo wants to do a "what-if' of the M3.  He is welcome to.  However, he has asked questions as to "why didn't they...?" And I have attempted to answer them.   The reason ultimately as to "why didn't they...?"  Was because they didn't.

I think he is trying to see where, as part of his backstory, he can insert a innovative personality that led to his what-if tank despite the doctrine or even effected a doctrinal change; granted it still doesn't explain why it would happen without the requisite experience.  The US Army doctrine, flawed as it might have been, wasn't just pulled out of someone's butt but was the result of the American analysis of Fall of France.  Nobody ever said the result of an analysis is always 100% correct- that's where subsequent experience comes in.

(Well I mean it's not that bad compared to my experience with some Sherman-hating and T-34-loving devotees who, when I brought up the survivability-enhancing field modifications of late Sherman models and the US Army's need to transport tanks across the Atlantic Ocean to counter their arguments that the Sherman had absolutely no value compared to any possible "American T-34" evolved from Christie's designs and was only ever accepted because of meddling by General Leslie McNair, practically got ready to go to war against my "trouble-making ploys" and make an example out of me.  I quickly realized that it isn't the kind of war I have the time for when the owner of the blog where the argument took place then accused me of supporting General McNair's opposition of introducing M26 Pershing despite the common knowledge that General McNair's tank destroyer doctrine didn't quite work out and my repeated expression of opinion that the M26 was the best tank in late WWII.  Then they of course ignored the fact that Sherman and T-34 actually crossed swords with success to each of their own during the Korean War.)

Nevertheless, I was going to wonder if the 3" gun would have fitted into the sponson mount of the M3 but ended up what-ifing one with the 76mm M1 instead because by the time such a need was felt, the lighter 76mm would probably have been what they'd go for......

[tomo pauk]

Tomo, if I may.

If a 'modifed' M3 were to be built, I doubt any on here would say anything but positives about it.  However, you're suggesting that it is an improvement than can be made within the timeframe they were built, but using hindsight and knowing the lessons learnt before they are given. 

A 'different model' is fine and dandy, but then to justify it with logic and/or knowledge that benefits from things that those within that timeframe had no access to is unreasonable and goes beyond 'plausible' into pure fantasy. 

Many on here like to see a 'plausible' take on whifs, especially if there is some detailed explanation associated with the conversion as you've suggested.  If it were merely built (or drawn) who's to complain?  Perhaps minor notes but beyond that, nothing much.  But put in a complex, detailed background and people will ask for much more 'reality' and a more realistic take on the modifications possible (using the knowledge that those building it would have had and not something that can be researched in the future).

I hope this is helpful in explaining why the questions are asked here,

Mav

There is really no need to explain about people questioning my ideas. I do hope that my answers were of good quality, and laid out in manners at least as good as the questions were asked.

[tomo pauk]

Tomo, if I may.
....

Mav, I fear that I have been led down a long, dark winding path on this one.  Tomo wants to do a "what-if' of the M3.  He is welcome to.  However, he has asked questions as to "why didn't they...?" And I have attempted to answer them.   The reason ultimately as to "why didn't they...?"  Was because they didn't.

The Allies didn't because they didn't have the experience which showed their previous decisions were wrong and when they got that experience they sought to correct their previous misconceptions and ultimately they played "catch-up" continuously, finding that their developments invariably lagged behind that of their main enemy.  Throughout that time they were dogged by doctrinal theories which proved inadequate in the face of the enemy and which also hampered their efforts to produce a tank which would beat the enemy.  Simple really and that answers all such questions.

Tomo, if you want to produce a "what-if" M3 Medium, go right ahead and I will praise it to the roof tops.  Please though, don't ask questions and then complain when the answers don't satisfy you because you aren't interested in them but rather interested in your own counter-factual history.

I now bow out of this thread.

My history don't claim that US tanks were not suppose to kill tanks, despite having AP ammo on-board. Neither it claims that 2pdr was good in tackling non-AFV ground targets. It doesn't claim that Pz-IV was heavy tank, either.
Hope I'll have your support to deny those claims, if laid out by someone else.