Category Archives: small hatch hull

Post # 68 The Chieftain’s Hatch does the M4A1, we review it.

Post # 68 The Chieftain’s Hatch does the M4A1, we review it: A great Hatch!

The video comes in two parts.

The subject of the video is  Black Magic, a small hatch, late production M4A1 if the turret came on it, though the turret or gun mount could be from other tanks. When it comes to restored Sherman tanks, I think being concerned about matching numbers is not a thing that seems to be worried about, and since it was so well designed and built, parts readily interchange. This sherman started life as a canadian Grizzly, basically totally the same as an M4A1 with an extra small hatch in the hull floor.

This tank has almost all the quick fix upgrades, the extra armor over the hull ammo boxes but lacks the cheek armor on the turret, and the turret may, I can’t tell for sure, have the cast in cheek armor, meaning it almost for sure didn’t come on the hull.  It also lacks the armor plates added in front of the driver and co drivers positions, that the Chieftain calls “sheet metal”.  It also has some late Sherman stuff, either added by the restorers, or by a depot rebuild later in the tanks life. The spot light, and ‘gun crutch’, or travel lock as normal people use were not on most small hatch shermans. Also the all around vision cupola would not be found on these tanks during WWII.

The Tom Jentz tangent. 

The Idea that the Sherman was no more reliable than any other tank, well, I don’t buy it. I like Mr Jentz’s work, and to some degree, his books helped inspire this site, since there was so little info on the web with really detailed info on the Sherman other than the Sherman Minutia site. I don’t think he really knows much about the Sherman if he thinks tanks like Panther and Tiger just needed more spare parts to be as reliable as the Sherman, it is a ridiculous idea. I do not think there was a single part on the Sherman that had a 500 kilometer life span, and that’s double the Panthers final drives.

First: The Chieftain himself has done Hatch posts on reports from the British, about how much more reliable, the M4A4 Sherman was than the Cromwell, even when both had full crews working to keep them running. both tanks were run thousands of miles, something late war German tanks could not do.

Second: In one of his own Hatches talks about the French experience with the mighty panther showed they averaged 150 kilometers per final drive set! Much less if the crew was hard on them.  There was no major automotive component including the oil, that had to be changed every 150 kilometers on any model of Sherman.

Third: This will focus on the Panther, since it was a major part of Germany’s late war armored force, and how terrible it was. This tank didn’t have just one flaw that should have disqualified it for production it had at least five. It was generally poorly reliable across all its automotive components, along with the final drive, 2500 kilometers for the motor and 1500 for the tranny were hugely optimistic and most of these tanks broke down and or were destroyed before they had to refuel. You had to take the whole drivers and co drivers compartment apart and the top of the hull off to change a transmission! Don’t get me started on the weak turret drive system that Rube Goldberg would have loved.  The  ‘wonderful’ dual torsion bar suspension and interleaved road wheels would cause any maintenance nazi to find the nearest US Line and surrender instead of working on it!

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Another thing to note, you can see the holes drilled vertically in the suspension bogies, these are the tops of the holes the bolts that hold the suspension caps on go into. They were covered up with body filler by the factory, but on most restored and old Shermans the filler is gone, and they don’t fill the holes.

Note: the odd groove in the center of the rear Hull casting, this wasn’t done on all M4A1 tanks, and may have been unique to General Steel castings.

On the problems with the R975, I have not heard of complaints about the engine being easy to blow, and would be very surprised if the throttle wasn’t governed to prevent it.  On having to crank the engine before starting, I have it on good authority, that the crew could just start the tank and run it for a few minutes every 45 minutes to an hour to avoid having to hand crank the motor.

Many of units removed the sand shields in ETO to prevent problems with mud.

The Commanders vane site is an early version bolted to a late war vane site pad. The tank has the early style gunner’s periscope.  The gunners periscope is missing the linkage going down to the gun.  The radio looks like a 528.  Note the Armored doors on all the ammo boxes and ready rack. The tank is missing a lot of interior storage, it may have been removed in preparation on shipping the tank out to it’s new owners.

I‘m no expert, but I think the Chieftain confused a .30 cal ammo bin for the 75mm ammo bin right next to his shoulder for the location of an SCR-506, I just can’t see a WWII radio fitting in the tiny box! You can see how sparsely filled the interior is, as issued the tank would be stuffed full of items to help fight it, live with it, or keep it running.  The Chieftain shows just how easy even a small hatch Sherman was to get out of,  the the Loader was still going to have some issues though.  I wish he would have tried the belly hatch out, but maybe it’s welded shut or something.

He covers the small floor hatch on the Grizzly tanks, and you get a nice shot of the early escape hatch.  They also show the generator mounted on the rear of the transmission in one of the shots, briefly.  You can also see the full turret basket’s mesh screening that separated the turret crew from the hull crew. Part of the quick fix was to cut this all out.  I suspect most of the inconsistencies in the tanks details are due to the restoration crew using the Sherman parts they could get their hands on.  Very few people would  even notice or know it had the wrong commanders hatch, or even whole turret.

A note on the tank, it belonged to a the Military Vehicle Technology Foundation, a fancy name for the collection of a man named Jacques Littlefield. He had a passion for armored vehicles of all types but really liked tanks. He restored many to full functionality, including working main guns and machine guns on some tanks.  Owning a working tank cannon is easier than you would think, and far easier than getting the paperwork approved to own machine guns in California, and Jacques Littlefield did both.  He employed a restoration crew with world class skills and did some amazing restorations, including a Panther A that was impossibly damaged, but still brought back to life.  That Panther was his crowning achievement, and he was a real mover and shaker in the international military vehicle restoration scene, seeing that tank run was one of the last things he achieved, because cancer claimed him shortly after.

The MVTF was supposed to make sure the collection of vehicles, that were a labor of love his whole life, lived on when he passed. Unfortunately the location of the MVTF, Portola California, on a large chunk of very private property, with very limited parking really presented some problem.  The collection was used often while it was there, by TV productions like Myth Busters, and was a staple for the Wargaming Staff for their productions, and occasionally opened up to groups of vets, or other interested people.  There were other difficulties with the location, and ultimately the collection was donated to the Collings Foundation.  They reportedly decided to keep 40 of the most significant vehicles and auction the rest off.  The money from the auction was going to be used to build a facility in Stowe Massachusetts, but due to zoning issues, the permits were not provided, leaving the vehicles they did keep in limbo.

I‘m sure the Collings Foundation, a really amazing Charity, they keep many rare WWII aircraft, and cars, including race cars running, has a plan for the rest of the tanks. Their website only lists the Panther in their collection, I hope that doesn’t mean they sold the rest when the museum fell through.  That’s not a criticism of the CF, they I’m sure know their business far better than I do, and they really are a top notch group of people. Just browse that site to see the airplanes they’ve gotten flying.  The only real B-24 liberator and a working F-4 Phantom are just two of the notable planes!!  If you know anything about aviation, you know just how complicated and expensive keeping an aircraft like a Phantom flying is, especially if you don’t have the resources of the U.S. Navy or Air Force backing you.

I have to say, this is one of the best Chieftain’s hatches they have done. Granted, I’m a tad biased, since it was on the Sherman, well a Grizzly made into a later model small hatch Sherman anyway, and the Chieftain really has gotten pretty good with the Sherman and its sub variants, and even has a book on US WWII TDs on the way.

 

 

 

#23 The US Firefly: No really!

The US Firefly: Yeah I said US Firefly, They Made Some But None Saw Combat, And They Were Unique And Not Like The Brit Ones.

The only known shot of the US Firefly tanks, also in shot, M22 locust airborne tanks
The only known shot of the US Firefly tanks, also in shot, M22 locust airborne tanks

Before the Normandy landings, the British had offered the US up 200 guns a month, if they were interesting in the 17 pounder gun. Their rearmament program was well underway, and would have enough Firefly tanks ready to go by D-Day. The US was not interested for a variety of reasons. The 76mm M1A1 and M3 90mm gun programs were well underway. Vehicles that used the guns were in the pipeline, even if there wasn’t much demand from the field yet. They did not want to complicate the supply situation with another tank ammo type.

Another reason was the 17 pounder did not really impress the US officers who witnessed test of it. It had both a large muzzle flash, and breach flashback, that hinted to them of a poor design. The efforts to convince the Americans of the errors of their ways went dormant along with the program. It wasn’t until the Ardennes offensive, when the US faced some heavier German armor, and in larger numbers than thought to be possible, that the program came back to life.

Conversions of 75mm armed US Sherman took place starting in March of 45. The US conversions were different in a few ways. The armored box on the rear of the turret was a little bigger to fit US radios, and the M2 machine gun brackets were welded to the end of the radio box. The tanks chosen for the conversions were all M4s, and M4A3. It’s possible some large hatch final production Shermans with all the improvements were a part of the 160 to 200 that were converted before the program was suspended.

No one has come up with what happened to the tanks, and it seems like none survived. None were ever issued to US units, it’s one of those little mysteries lost to the archives and or time.

Sources: Armored Thunderbolt by Zaloga

#3 The Sherman Variants: The Design Matures

The Sherman Variants: So Many Shermans, so Confusing! Updated 4/13

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M4A4’s in desert training center in California.

First off, Americans referred to the Sherman as the M4, or M4 Medium, or Medium, the Sherman name was not commonly used until post WWII. The British came up with the name for the M4 and referred to it with their own designation system that is covered in more detail later. They also named the Lee, and Stuart, and at some point the US Army just stuck with the naming scheme. The full story behind this is still a minor mystery, with US war time documents confirming the ‘general’ names were at least used on paper by the US Army during the war.

Now let’s cover the factory production versions of the Sherman. Also keep in mind; it is very hard to define just how a Sherman may be configured without really knowing where and when it was produced. In some rare cases, large hatch hull, 75mm armed Shermans got produced with normal ammo racks, when the norm for large hatch hull tanks was wet ammo racks.

Then you have post war rebuilds, where the Army swapped 76 turrets onto 75mm M4A3 HVSS hulls during depot level rebuilds.  It would not be impossible for a field repair depot to swap a turret from one knocked out tank, onto the hull of another, making an oddball. You also have to take into account post war monuments are sometimes Frankenstein tanks, in one case with a T23 on a small hatch hull.  You can also run into a Frankenstein tank in museums, or post war civilian restorations. In many cases museum tanks are old range relics that need restoration, in some cases the tank was in decent shape and a cosmetic restoration can easily be done. For the civilian tanker, who wants a running Sherman, also has to get them from a gunnery range, then, the long process of rebuilding the tank can start. I link to a few places that cover a restoration, and these guys do amazing work, taking tanks that you could never imaging running or looking like a tank again, and bringing them back to life.

The nice thing about a tank, as far as a WWII collectable vehicle goes, say compared to an Airplane, like a P-51 or even SNJ, is tanks won’t breakdown, and kill you by falling out of the sky. If you make a big error in a tank, at worst, you’re going to take out a building, flop it on its side, or sink it in deep mud or something, all not really life threatening.  Once you have the tank, running it is going to be a lot cheaper than a vintage aircraft as well.  The other nice thing is if you’re handy, you can work on it yourself, without having to get a certified aircraft mechanic to sign off on all your work.  You do need a hell of a lot of heavy equipment to really work on a tank though, but you don’t have annuals, and hanger rental costs! This may be why the hobby of owning a tank is becoming more popular in the United States!

M4DV
M4 DV early Sherman tank. Because the M4 started production after the M4A1 and M4A2, and M4A4 it started production with cast differential cover, and heavy duty suspension, but still had DV ports.

M4 Sherman: First in Name, 4th Into Production. 

These tanks used the same R975 motor as the M3, and M3A1. The vast majority of the bugs in this automotive system were worked out before the M4 even started production. This really helped give the Sherman its reputation for reliability and ease of repair. The M4 had a welded hull with a cast turret mounting the M3, 75mm gun. Early variants had three hull machine guns, and two, turret mounted machine guns. The hull guns were all M1919A4 .30 caliber machine guns, two fixed, and one mounted in a ball mount for the co-drivers use. The fixed guns were deleted from production very rapidly. The turret armament remained unchanged for the whole production run: Using the M3 75mm gun with the M1919A4 coaxial machine gun and M2 .50 caliber mounted on the roof. The turret would be the same turret used on all early Shermans and would be interchangeable on all production Shermans. This version was not produced with the later improved T23 turret but did get some large hatch hulls in special variants.

M4105W
M4 105, this tank does not have the factory installed front sprockets

There were two variants of the M4 to be built with the large hatch hull. The first, the M4 (105) was a large hatch hull mated to the 105mm howitzer, on the M52 mount, in the standard 75mm turret. These hulls did not have wet ammo racks or gyro stabilizers, and the 105mm turrets had an extra armored ventilator, the only turrets to have them. The M4 (105) gun tanks had a special mantlet, with four large screws in the face, unique to 105 tanks. Production started in February of 44, and continued well into 45, with late production M4 (105) tanks getting HVSS suspension. These tanks were used as replacements for the M7 Priest in tank units, and spent most of their time being used as indirect fire support, like the M7 they replaced. These tank also had exhaust deflecting vents installed in the back to help reduce dust from being stirred up.

 

 

M4Composite
M4 composite hull, small hatch hull, late 75mm turret with loaders hatch

One other variant of the M4 to get the large hatch hull(100 or so small hatch casting were made as well) was the M4 ‘hybrid’, this hull was welded, but used a large casting very similar to the front of the M4A1 on the front of the hull. It was found that most of the welding hours building the welded hull tanks were spent on the glacis plate. They figured out by using one large casting, incorporating the hatches and bow gun would save on welding time and labor costs.

These M4 hybrids were used by the British to make Ic Fireflies. They liked the 75mm turret these tanks came with since many already had a loaders hatch, this saved them time on the conversion since they didn’t have to cut one. Most of the M4 composite tanks were shipped to Europe or the Pacific, making survivors rare.

The M4 along with the M4A1 were the preferred US Army version of the Sherman until the introduction of the M4A3. This tank was made in five factories from July of 42 to March of 45, 7584 produced. As far as the US Army was concerned, the M4, and M4A1 were interchangeable.

M4A1 Sherman: First Into Production, And When It Did Go, It Was The Most Advanced Tank In The World.

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Early M4A1 Sherman from the 9th Queen’s Royal Lancers,  gathered up just before the start of Operation Lightfoot, the second battle of El Alamein. The photo was taken in late October 1942  and at this time the Sherman M4A1 was a cutting edge tank
M4_Sherman
M4A1 76 w, much like the type that would be used in Operation Cobra, beautifully restored.

This was virtually the same tank as the M4, with the same motor and automotive systems and armament. The key difference was the cast upper hull. This huge upper hull casting was one piece. This was a very hard thing to do with casting technology at the time, and something the Germans could not have reproduced, they lacked the advanced technology, and facilities needed to do so. Everything from hatches to wheels, and turrets, and guns were interchangeable with the M4 and other Sherman models. This version saw production longer than any other hull type. It also saw all the upgrades like the improved large hatch hull with wet ammo racks, the T23 turret with 76mm gun, and HVSS suspension system. It was 30 of these M4A1 76 HVSS tanks that were the last Shermans ever produced. The M4A1 was also the first to see combat use with the improved M1 gun and T23 turret during operation Cobra. These tanks would also be the basis for the Israeli M51 Sherman. Three factories produced 9527 M4A1s with all turret types from Feb 42 to July of 45.

The US Marines used one battalion of these tanks on the Cape Gloucester campaign, all small hatch M4A1 75 tanks. This was the only use of this type by the U.S. Marines.

M4A2 Sherman: The Second Sherman Into Production!

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Mid-production small hatch M4A2, courtesy of the Sherman Minutia site.
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A late production M4A2 76w, probably produced by Fisher, in Soviet use.

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This version of the Sherman used a welded hull nearly identical to the M4, but with a pair of vented armored grates on the rear hull deck. The M4A2 tanks used the GM 6046 twin diesel. This version was produced with all the improvements the other types got, like the large hatch hull with wet ammo racks, the T23 turret with improved M1 gun, and HVSS suspension. This version would see very limited combat in US hands, most being shipped to Russia with a few early hulls going to the Brits and USMC. This was the preferred version for Soviet lend lease deliveries, since the USSR was using all diesel tanks. It was produced in six factories with 10,968 of all turret types produced from April of 42 to July 45.

M4A2, M10, M36B2 clutch lockout unit

A little trivia about this version, the Sherman used in the movie Fury, was actually a late production M4A2 76 HVSS tank. The only way you can tell a late A2 from a late A3 is by the size of the armored grills on the back deck. They did a great job of hiding this area in the movie.

The Marines operated a lot of small hatch and a fairly large number of large hatch M4A2 tanks, until the supply of 75mm armed versions dried up in late 1944. Then they switched over to large hatch M4A3 75w tanks, but there were some A2 holdouts amongst the six battalions.

m4a2 early side M4A2 early early bogies small gun shield M4A2 early production, early bogies

 

M4A3 Sherman: The Best Version Of The Sherman, Both in 75mm and 76mm

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Large hatch M4A3 75w
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M4A3 76w HVSS tank, near Bastogne during the battle of the bulge. The Tank is with the 35th Tank Battalion, 4th AD. The photo was taken January 8th 1945

This would be the base for what would be the final Sherman in US Army use, seeing action all the way out to the Korean War in US Army hands. This tank had a welded hull just like the M4, A2, and A4, but used a new motor. The Ford GAA V8, this motor took some time for its bugs to be worked out, so unlike say, the Nazi Germans, the US Army didn’t use it until it was ready for serious production. When it was, it became the preferred US Army version of the tank in both the 75mm and 76mm armed tanks. It would see all the improvements, and be the first hull type to take the HVSS suspension system into combat for the US Army. The M4A3E8 or M4A3 tank with T23 turret and HVSS suspension bolted on would be the final and ultimate US Army Sherman. It would be produced in three factories with all turret types, 12,596 built in total between June 42 and June of 45.

M4A3 instrament panel, late
M4A3 76w Instrament Panel

After WWII when the Army wanted to standardize on one Sherman type, any M4A3 large hatch hull they could find would have a T23 turret and HVSS suspension installed on it. The Army was so thorough in these conversions no M4A3 large hatch 75mm gun tanks are known to have survived with the original turrets installed.  Any M4A1 HVSS 76 and M4A2 HVSS 76 tanks in Army inventory would have been robbed of their suspensions and turrets so they could be installed on M4A3 large hatch hulls.

M4AE2-SHERMAN-JUMBO
M4A3E2 Jumbo

M4A3E2_36

M4A3E2 Jumbo

The M4A3E2 Jumbo: Fishers Fat and Special Baby!

FTA was the sole producer of one very special variant of the Sherman, the M4A3E2 Jumbo. This version of the Sherman was the assault Sherman, though not expressly designed for it, was manufactured to be able to lead a column up a road and take a few hits from German AT guns or tanks so they could be spotted without having to sacrifice the tank. It had a lot of extra armor, and could take a lot of hits before being knocked out, but was still not impervious to German AT gun fire. Only 254 of these tanks were produced, and all but four were shipped to Europe for use by the US Army. They were all armed with the M3 75mm gun. There was a surplus of M1A1 76mm guns in Europe due to an aborted program re arm 75mm Sherman tanks with the guns. Many of the Jumbo’s ended up with these guns, but none were ever factory installed.

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The tank was no different in automotive components from the M4A3 tanks, with the sole difference being the slightly lower final drive gear ratio, going from a 2.84:1 ratio in the base Shermans, to 3.36:1 on the Jumbos. This reduced the top speed slightly but helped the tank get all the extra armor moving. The Jumbos were well liked by their crews and in great demand; no more were built though, the only batch being produced from May to July of 1944.   Had the invasion of Japan been needed, a special Jumbo with larger turret that included a flame thrower was considered, but we all know how that story ended.

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The M4A3 (75)w and later 105 was issued to the Marines when the M4A2 75mm tanks went out of production. These would all have been large hatch M4A3 75w tanks, and they may have gotten some with HVSS.

M4A3-Sherman-105mm-Dozer-latrun-1

M4A4 Sherman: The Sherman No One Wanted At First, But In The End Was A Very Important Model,  At Least To The British

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M4A4 being used by the French

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M4A4OTHERSIDE M4A4 SIDE M4A4 rear M4A4 DV M4A4 OFSET m4a4 FRONT SIDE

This tank is the oddball of Sherman tanks. It had a welded hull and used the A-57 multibank motor. A tank motor made from combining five car motors on one crank case. As complicated as this sounds, it was produced in large numbers and was reliable enough to see combat use, though not in American hands in most cases. In US use they tried to limit it to stateside training duty. The Brits found it more reliable than their native power plants and liked it just fine. The A4 version never got the improved large hatch hull or T23 turret with M1 gun. Most were shipped to the Brits via lend lease and many were turned into Vc Fireflies, making it the most common Firefly type. The US Marines operating these tanks in the states as training tanks, 22 of them for two months before they were replaced by M4A2s. This tank had a longer hull, like its Lee cousin to accommodate the big A-57 motor. It was the first Sherman version to go out of production. It was produced in one factory (CDA) from July of 42, to November of 43 with 7499 built.

chrysler-a57-multibank-installation
The massive A57 motor being installed at CDA

The A4 has the honor of being the heaviest and largest standard Sherman. The larger hull to accommodate the A57 motor, and the motor itself added weight. The British used these tanks extensively in combat. These tanks show up in British test reports as well, often pitted against tanks like the Cromwell, in reliability or other tests, and usually coming out ahead. Anyone who has ever changed the spark plugs on their car should really be able to appreciate how hard a motor made by tying five six cylinder automobile engines together, on one crank would be. It is easy to identify an A4 from the side, there’s a bulge on the engine deck just behind the turret, and a bulge in the belly in the same place, both to house a huge cooling fan. The bogie assemblies are spaced further apart, this is very obvious compared to the rest of the Sherman models, and also required a longer set of tracks. These longer tracks spread the added weight out, so it had no effect on flotation.

M4A4 small hatch storage
M4A4 early ammo layout. This would be the same ammo layout on all early tanks before the armor was added to the hull sponson ammo racks and the ready ammo around the turret basket base was removed

It turns out this version of the Sherman served with more nations than any other version! These include Britain, Canada, South Africa, New Zealand, Czechoslovakia, India, China and the USA, all used this tank in combat at some point. I find it very interesting the most complicated Sherman saw such widespread use, and still earned a reputation for reliability second to none. The majority of the British Shermans on D-Day were this model as well.

For a tank the US Army didn’t want, it had an excellent combat record, with the nations that got stuck with it.  The M4A4 is one of the rarest Shermans to find running with its original motor. The A57 would be very troublesome to keep running for a civilian hobbyist, and I have my doubts about how easy it is to get Chrysler inline six parts in Europe. Few M4A4’s remained in the United States, since the ones used in training were refurbished by Chrysler and then shipped off to the UK for conversion to Fireflies.

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All Sherman variants share a lot of details and most spare parts interchange. Only the motors really call for different parts. All early Sherman tanks had 51mm of armor at 56 degrees on the front hull, and 76mm on the front of the turret. The 56 degree hulls are called small hatch hulls because the driver and co-driver had small hatches that forced them to twist sideways to get in and out. They also started out with direct vision ports along with periscopes for crew vision. Even the cast tanks matched these specs and the hatches from a cast tank could be used on a welded tank.  These early hulls had some of the ammo racks in the sponsons above the tracks. Not a great place for ammo, but not an uncommon one for it either. As they improved the hull, they added plates over the direct vision ports and eventually removed them from the castings. Large plates were eventually welded over the ammo racks on the sides, and this extra armor was eventually just added into the casting on the cast hulls. It’s safe to say no small hatch tanks were factory produced with a 76mm gun or improved T23 turret.

The major hull change came when they upgraded the drivers and co drives hatches making them bigger. They also thickened the front armor to 64mm but reduced the slope to 47 degrees to fit the new driver’s hatches.  The M4 (hybrid and 105 only), M4A1, A2, and A3 were produced with these improved large hatch hulls. Many of these improved large hull tanks had the original 75mm gun and turret. Even the M4A3 with HVSS suspension was produced with the 75mm gun and turret. Most of the large hatch production was with the new and improved T23 turret.  These larger hatch hulls would still accept the majority of the spares the older hulls used and the lower hull remained largely unchanged and would accept all the suspension types. Any large hatch M4A3 hull was likely converted to an M4A3 76 HVSS post WWII.

Through the whole production run minor details were changed. The suspension saw many different version before the final HVSS type was produced. The track types also changed and there were many variants made from rubber and steel, or steel. There were even at least six different types of road wheel! There are so many minor detail changes, the scope is to big to cover in this post, needless to say, the only other tank I know of with so many minor changes over the production run was the Tiger, and in the Tigers case it’s just sad, with so few produced, it means almost no two tigers were the same. This was not the case for the Shermans and the changes did not slow production down at all and in many cases were just different because a particular part, like an antenna mount, or driver’s hood, could have been sourced from a different sub-contractor, and the parts may look different, but would function exactly the same. Tiger parts are not good at interchanging without modification, and a crew a craftsmen to custom fit them. The changes made to the Sherman were either to incorporate better parts, or to use a locally made substitute part for one in short supply, so making their own version allowed them to continue production without a slowdown.

To really get a handle on these differences there are two really great sources.

This is the easy, way: Sherman Minutia site  a great site that really covers the minor detail changes on the Sherman tank very well.  You can spend hours reading it and looking over the pictures. It explains little of the combat history of the Sherman but covers the minor changes on the vehicles themselves very well. You can spend hours on this site learning about minor Sherman details. It is also a primary source for this post.

Another great way is to get a copy of: Son of a Sherman volume one, The Sherman design and Development by Patrick Stansell and Kurt Laughlin. This book is a must have for the Sherman plastic modeler or true enthusiast. It is filled with the tiny detail changes that took place on the Sherman production lines from start to finish. They cover everything from lifting eyes to ventilators, casting numbers, to most minor change to the turrets. Get it now before it goes out of print and the price skyrockets. I liked it so much I bought two!

The turret saw continual change as well, but remained basically the same. The 75mm gun never changed but its mount and sighting system did. The turret lost the pistol port, and then gained it back. It gained a rotor shield over time and an extra hatch. All these detail changes are covered on the site above and in the Son of a Sherman book. The important thing to note was the tank saw continual improvement to an already reliable, and easy to produce design. The Sherman was easy to produce for an industrial nation like the USA, but beyond Nazi Germany’s technical capabilities for several reasons, like large casting and the gun stabilization system, or even multiple reliable motors to power the tens of thousands of tanks made.

In the basics section I’m only going to cover one more thing. The Sherman tank was not as blind as the tanks it faced. The M4 series, from the first production tank, to the final Sherman that rolled off any of the production lines, were covered in periscopes or view ports for the crew. The gunner had a wide angle periscope that had incorporated the site for the main gun, and they very quickly added a telescopic site to go with it. The commander had a large rotating periscope in his rotating copula. The loader had a rotating periscope and the driver and co-driver had two, one in their hatch, and another mounted in the hull right in front of them once the DV ports were deleted (non-rotating). Later version added a direct vision cupola and a periscope for the loader in his new hatch. All these periscopes could be lowered and the port closed, and if damage easily and quickly replaced from inside the tank. All this gave the Sherman an advantage in spotting things outside the tank; they were still blind, just not as blind as most of the tanks they would face. Finding an AT gun in a bush could be very challenging for any tank, and infantry if not scared off by the presence of a tank in the first place can sneak up on one pretty easy.

This was a big advantage when it saw combat and throughout the tanks career it was always one of the best if not the best tank of the war. It was reliable, the crew had a good chance of spotting enemies before other tank crews, the gun was stabilized, fast firing, and accurate. It was as good or better than most of the tanks it faced, even the larger German tanks. These tanks were largely failures, with only long debunked Nazi propaganda propping up their war record. The Sherman has the opposite problem.

Smiling_British_Soldiers_in_M4_Sherman_Tank_1943

Sources: Armored Thunderbolt by Zaloga, Sherman by Hunnicutt, Combat Lessons, Son of a Sherman by Stansell and Laughlin,  M4 Sherman tank at war by Green, Tanks are a Might Fine Thing by Stout, TM9-752, TM9-754, TM9-759, TM9-731B