"Sherman I firefly vs Sherman V firefly" Topic

Were these mixed like a firefly is a firefly and so brigades would have both or did some units get priority for the V versions?

My understanding is there weren't many I's made so there wouldn't have been a lot of mixing. The engines were different so it would have made sense to group all the I's both Firefly and standard 75mm tanks together, but whether it actually happened or not I don't know.

From what Ive seen, the 1c's were with the cast hull/Hybrid M4 equipped units but any replacement Firefly for these units were more likely to be the Vc post Normandy. Early on there was a shortage of Fireflys so might have seen a 1c with a V 75mm equipped unit but I doubt it.
L

They would have made every attempt to keep the Sherman 1C together in a unit equipped with Sherman 1, as they all had the same radial engine.

Equally, the Sherman VC wold have been used by units equipped with Sherman V. All having the Chrysler multibank.

Maybe some explanation of the terminology might help.
US, M4 et cetera, the A1 or A2 denotes the type, the E* the suspension.

UK, Sherman I to V, denotes the type, the letter denotes any special weapon, A=76mm, B-105mm and C- 17 pdr. Additionally a Y could mean the E* suspension.

Let's go through this a bit.
M4-radial engine- Sherman
M4A1-radial engine-Sherman ll
M4A2-GM twin diesel engine-Sherman lll
M4A3-Ford engine-Sherman lV
M4A5-Chrysler multibank-Sherman V
M4A6-Guiberson |Diesel engine-Sherman Vl

So, a Sherman VC is a Chrysler multibank engined Firefly.
Or a Sherman lllAY is a M4A2 gm twin diesel with the 76mm and the late war easy eight suspension.

They would have made every attempt to keep the Firefly in a unit equipped with the same engines. Only desperation or shortages would have altered the habit.

Long winded, but I hope it helps.

There are a few figures available for 1945 holdings in 21AG re Ic and Vc issues;

From late Jan45 to late Feb45 11th Armd Div reported around 24 Ic to approx 60 Vc.

From mid-Jan45 to early Feb45, 33 Armd Bde had 60 Ic to 20 Vc. When they converted back to tanks after being on LVTs for a spell all their 17-prs are shown as Ic.

For Apr45 4th Armd Bde was around 48 Ic to 24 Vc.

For Jan-Feb45 7th Armd Div was 50+ Ic to around a dozen Vc. Their 17-pr stocks then fall off a smallish cliff for March and April 45, finishing at 29 Ic and 7 Vc.

8th Armd Bde figures change a lot, in the region of 55-65 Ic and 20-30 Vc, the latter dropping to 15 then 12 by Apr45.

Gds Armd Div show approx 30 Ic from Jan to end Mar45 versus about 24 Vc, then in Apr45 Ic drops to around 18 and Vc stays around 30.

It looks like Ic gained prominence as the campaign unfolded, I don't think there are any listed in the Jun44 RAC holdings. The Dec44 figures used to be online, not sure if they still are (I couldn't get hold of a copy of the original when I was searching way back).

Gary

It looks like Ic gained prominence as the campaign unfolded, I don't think there are any listed in the Jun44 RAC holdings.

‘Sherman Firefly' by Mark Hayward gives figures for 1st Polish Armoured Division having two ICs as of 30 June 1944. No other unit has ICs at that time. The book also confirms that by war's end the IC was more common in NWE than the VC.

Troopwo;

Your M4A5 should read M4A4. If I remember correctly the M4A5 was a designation allocated by the US for, but not used by, the Canadian produced Ram. This tank carried the Sherman VI designation by the British. The M4A6 was the Sherman VII.

Yeah, vision problems.
Last two should be M4A4 multibank and M4A5 Guiberson

Now I'm curious, why would the IC (older model) become more prominent later in the war? Had they run out of Vs to convert to 17pdrs? And started to converting the older stock?

I would drop all references to the M4A5. Last line just change Sherman VI to VII. Interestingly enough the M4A6/Sherman VII's radial diesel engine was built by Caterpillar.

As to IC being more prominent the problem was suitable tanks available. The US had begun phasing out 75mm armed Shermans. The M4A4 (Sherman V), for example, was phased out in the 3rd quarter of 43. The British turned to available 75 mm armed Sherman I and Sherman I Hybrids to make up for the lack of Sherman Vs.

Maybe some explanation of the terminology might help.
US, M4 et cetera, the A1 or A2 denotes the type, the E* the suspension.

I'm afraid it is not quite that simple.

The A1 or A2 does indeed denote the type. Meaning it denotes the major production series.

In US designations:
M4: Welded hull, Continental radial engine.
M4A1: Cast hull, Continental radial engine.
M4A2: Welded hull, GM diesel engine.
M4A3: Welded hull, Ford V8 engine.
M4A4: Lengthened welded hull, Chrysler multi-bank engine.
M4A5: None. This designation was not used.
M4A6: Lengthened composite hull, Caterpillar multi-fuel radial engine.

But the E* does NOT denote the suspension. It denotes an experimental model, in sequence, whatever the issue of experimentation was. It might be suspension, it might be armor, it might be the armament, it might be Friday night lights.

It does not denote anything in a production Sherman, because the E* was dropped when the tank with the E* went in to production. At least officially. But the US Army's official designation scheme was so obtuse the troops might have called it almost anything, including using the E* designator.

An M4A3E2, was an up-armored M4A3 (75), meaning it was the 2nd experimental extension of the M4A3 (the major production variant with the Ford GAA engine and a welded hull). It was accepted for production, and the troops typically called it a "Jumbo".

An M4A3E4 was an experimental mounting of a 76mm M1 gun in a standard M4A3. Ordnance had completed and approved this variant, and recommended production by the end of 1942. The Armored Board rejected it.

An M4A3E8 was an experimental mounting of the HVSS suspension system on an M4A3(76)W (late production M4A3 with wet ammo storage and 47degree glacis, with 76mm gun in a T23 turret). It was accepted for production as the M4A3(76)W HVSS. The troops typically called it an E8 or "Easy 8".

An M4A3E9 was a late-war re-manufacture to add applique armor.

Now I'm curious, why would the IC (older model) become more prominent later in the war? Had they run out of Vs to convert to 17pdrs? And started to converting the older stock?

Sherman I was not an "older model" than Sherman V. One should not read the sequencing to indicate newer or older.

M4 and M4A4 were produced concurrently. The US Army continued to order (and so production continued on) M4 models through the fall of 1944. This was because it was the only version with a radial engine to be adapted for a 105mm howitzer assault gun. The US Army wanted 105mm Shermans in every formation. Those with radial-engined Shermans (M4 or M4A1) got M4(105)VVS.

That's not to say that the British didn't replace deliveries of one with the other. I don't know how the British purchasing worked. It could well be, since any M4 (Sherman I) volume was in competition with US Army requirements. But by 1943 the US Army standard was M4A3, with M4 or M4A1 serving as "alternate standard". This means they bought M4A3s first, but to fill in from limited capacity they also bought M4s and M4A1s to make up the difference (in particular because until full units could transition to M4A3 they got M4 or M4A1 replacements as the Army wanted to equip whole units with the same engine). Could well have been much the same for M4A4 (Sherman V) vs. M4 (Sherman I) for the Brits.

-Mark
(aka: Mk 1)

Indeed it is never simple. For example the M4 being listed as a welded hull. The majority were but in August of 43 Chrysler began production of the M4 with a cast front end somewhat similar to the M4A6. For some reason, known only to bureaucrats, the Army chose NOT to give this model a designation to distinguish it from the welded hull versions.

A popular, but never official, term used by the US was to call this the M4 Composite. The British dubbed it the Sherman I hybrid.

link

Could well have been much the same for M4A4 (Sherman V) vs. M4 (Sherman I) for the Brits.

That would tend to imply that supplies of the M4A4 were proving inadequate as having more or less standardised on it I'm sure the British would have preferred to stick with just one model. Were they tailing off M4A4 production by late ‘44?

The last of the new M4A4s rolled off the production line in the 3rd quarter of 1943.

Gunfreak, not neessarily older models.
Many were built at the same time at different plants.
the reason for all the variety was due to the inability to produce enough engines for all of them.

They realized the Chrysler multibank was not the best solution, so production ended a bit earlier. Most were given to the British whee tinkering with an engine is an artform and they made them work. Many were lept in the US for training until the US built enough of the models they preferred. Once they had enough, they put older modeles through a refurbishment program and overseas they went.

Additionally, the UK was notorious for converting tanks to special purpose or funnies. It was actually a point of contention with the US.

At one point, the US built and dedicated its' first computer to keeping track of where all the Shermans went and who has them and hat the priority should be.

Seriously, there is no rhyme or reason.

the reason for all the variety was due to the inability to produce enough engines for all of them.

As usual, there's more to this than that.

The M4 & M4A1 used the same engine, but not all factories could produce a casting large enough for the M4A1 hull (the version the Army wanted & the version the prototype was), so the welded hull was designed to get hulls into production using what industrial resources existed. Fate would ahve it that the welded hull version would be produced first so got the M4 designator. The superior ballistic qualities of the cast hull were still desirable, so the Composite was developed to take advantage of the ballistic properties of cast armor where it mattered most…in the front hull.

The other variants were designed again to maximise industrial capacity, not necessarily because enough engines could be produced, but rather to take advantage of existing industrial resources to get as many hulls into service as quickly as possible.

Damon.

Garand:

I had always heard / read / understood that it was a bit different from what you have described regarding the M4 vs. M4A1.

The intention, from the start, was to use welding and casting for production of the Sherman. The cast hull was a method of reducing production costs and time -- it was much faster to build a cast hull, once you had the casting. But there was limited foundry capacity for such large and heavy castings, so while a cast hull was faster and cheaper to make, there was no immediate way to make enough of them.

Because of this, development proceeded on both in parallel.

As it was, the cast hulls were available sooner, both for prototyping and for production. In the US Army and the British Army, the M4A1 (Sherman II) was available in useful numbers before the M4 (Sherman I). Both were produced in parallel, it's just that it was faster to make M4A1s (and until the cluster of several second-tier producers scaled up, there was not much capacity devoted to M4s).

It was all about production -- to my understanding there was no significant thought that the cast hull gave better ballistic protection. In fact, there was a deliberate effort to make match the protection levels between the cast and welded hulls, but it didn't work because the cast armor turned out to be notably weaker than the rolled homogenous armor used on the welded hulls.

The composite hulls were a Chrysler idea to reduce the cost and production man-hours for welded hull Shermans (both M4 and M4A4). Original Sherman welded hulls could already be considered to be composite (to a limited extent) on the front -- the driver and co-driver positions (the protruding bulges with the "narrow" hatches) were castings that were welded into the flat main front slope plate. Chrysler engineers just said hey, rather than welding two castings into a rolled plate and then welding that assembly onto the sides of the hull to form the front, it will be less work to make a single larger cast piece and weld it onto the sides of the hull to form the front.

Again, it was all about production.

The whole composite Sherman production program was pretty short-lived. Seems to have been started in early/mid-1943, with production ending by the end of 1943 (maybe a few in January of 1944). But then, the whole Sherman program was pretty quick, given the enormous number of tanks produced.

Sherman production really only scaled up for about 3/4ths of year (1942/43), peaked for about 3/4ths of a year (1943), and then scaled down for about another 3/4ths of a year (through Q3 of 1944). When you put together such a massive industrial undertaking that you can build 2,000 tanks per month, you don't need more than about two and a half years to build a WHOLE LOT of tanks!

Or so I understand. Could be wrong. Be interested to learn if I am.

-Mark
(aka: Mk 1)

Oh and BTW, before someone else points it out, I thought I might correct the guy who said this, too:

An M4A3E9 was a late-war re-manufacture to add applique armor.

Nope. No no no. The E9 was indeed an alternative for suspension. It was a VVS system that was spaced outwards from the hull, to allow duck-bill extenders to be fitted not only to the outside, but also the inside of the tracks. It was seen as a way to improve flotation. Evidently some units did go in to production, although once HVSS Shermans (the E8 which PRECEDED it) were in production it was no longer useful or needed.

How could you get that one wrong anyway? Some guys'll just post any random non-sense ….

-Mark
(aka: Mk 1)

The above discussion confirms my understanding that the various marks of Sherman were production variants and not development variants. Are there, though, any material difference in the defensive capability of the various types? I would guess not, as production overlapped?

It's said that not a month passed by or some upgrade was done at the factory or the introduced a new "upgrade kit" to be installed by units in the field because sending tanks back to the factory was not an option.

These upgrades could be anything from a new more reliable fuse box or standardized infantry telephones mounted on the back to a new hatch for the loader which required maintenance to cut a hole in the roof, drop in the hatch, weld it in place and gain the eternal admiration of the loader who could now get a breath of fresh air, had an extra way to dispose of empty shells and didn't have to crawl under the 76mm gun to get out when the tank happened to be on fire.

All these upgrades made life for Sherman crews much easier, but are largely ignored by the monomaniacal crowd who only respond to big guns and thick armour.

The last of the new M4A4s rolled off the production line in the 3rd quarter of 1943.

That would explain why the British moved to Sherman I's for Firefly conversions then! I presume the same thing applied to 75mm armed tanks and that the Sherman V gave way to Sherman I's.

Most were given to the British whee tinkering with an engine is an artform and they made them work.

Tinkering is a bit of an understatement. Keeping the engines in synch was a major problem and even simple maintenance required the engine to be pulled.

Would it be appropriate to give sherman I /IC two turret hatches? I know they came standard with just commander hatch. But I've heard/read that they cut a gunners hatch into turrets that only had commander hatch.

@ gunfreak

Good option to distinguish one unit from another I'd have said.

Production figures for all types of Shermans by quarter:

42-01 12
42-02 296
42-03 2,670
42-04 5,039
43-01 5,708
43-02 6,053
43-03 5,771
43-04 3,731
44-01 1,894
44-02 3,356
44-03 3,654
44-04 4,275
45-01 4,076
45-02 2,687
45-03 30

Numbers courtesy of "Son of Sherman Volume 1: The Sherman Design and Development" Patrick Stansell and Kurt Laughlin, Ampersand Group 2013

As you can see after a scaling down of production starting in 4th Quarter of 43 and even more so in 1st Quarter of 44 and then production once again began to rise.

Excellent informative post gentlemen.

One question I have always thought about is the difference in combustibility between the diesel, gas and ave-gas models. Would a crew feel more safe in a diesel? Is there any merit in the difference or is it just a matter of other combustibles in the tank causing fire?

Though diesel fuel has a higher flash point than gasoline, fuel types played little role in the vulnerability of a tank. Much more important was design of the tank. Especially how well fuel tanks and ammunition storage was protected.

Case in point is the Sherman. Earlier, so called "dry stowage" Shermans had a propensity to brew up when penetrated. The switch to "wet stowage" brought a remarkable turn around. After the war it was found the water filled stowage racks (hence the nickname "wet stowage") had little to do with the survivability of the tank. Rather it was the fact ammunition stowage in wet stowage tanks were moved out of the vulnerable sponsons to a position lower in the hull where the suspension provided much better protection.

And one last thing. For some odd reason many think one reason German tanks were less likely to burn is because they used diesel fuel. Of course they didnt. The vast majority of German tanks used gasoline engines.

Thanks Marc!

Gunfreak, the breech on the gun of the 17pdr is enourmously long. When they did the gun conversions, one definite feature was to add the hatch just for the loader. Normally a rectangular job. If the model already had a separate hatch for the loader, I can't see why they'ld have changed it. It would have stayed.

Wrgmr, for the Shermans, the combustabilitlity issue tended to be more a point of ammo fire and detonation rather than fuel. All the marks that went through refurb in '43-44 had extra plates of armour welded on to the front of the turret and the sides of the hulls.
It was only the later marks that started getting the 'wet' stowage that really dropped the problem dramatically.

As an example, all the Churchills were gasoline engined. No problem in bursting into flame there. It was all due to better ammo stowage in lower places away from the flying slag.

troopwo – I recall German gunners used the welded plate on the side sponson as an aiming point, knowing full well that was where ammo was stored.

It was a question because Bob Crisp wrote about it in Brazen Chariots, that Honey's had an aircraft engine and used high octane fuel. That is was highly combustible.

Actually the story about using the welded plates as aim points is apocryphal. Unless close up it would be hard to make out the plates. Further the plates were extra armor. Makes more sense to aim between them actually.

Well, high octane is a relative term. High octane for the US meant 115/145 or 100/130. High octane for the Germans meant 80/87 (it's why they had to go to Methanol/Water mixes and Nitrous Oxide).

But the big R-985 radial in the Honey and Sherman runs just fine on 87.

Further the plates were extra armor. Makes more sense to aim between them actually.

Apparently it wouldn't have made any difference. To quote the Twenty-First Army Group Operational Research Reports 1944-45 "in no recorded case has the extra outside applique armour resisted any hit".