Tag Archives: HVSS

#34 Israeli Shermans: The Most Powerful Shermans Ever To See Action.

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Israeli Shermans: These Modifications Kept The Sherman Relevant Into The 70s!

Israeli use of the Sherman tank would be long and glorious, with updated models using extremely upgraded guns, seeing action for decades after WWII. They would use the chassis for more things than the US Army did. They also went with their own strange naming system, making trying to figure out the Israeli Shermans even harder. There is also not a lot of good books in English on the subject, and Hunnicutt only has a little info on them and I think it’s a tad out of date. This section will be updated as I find out more info on the subject and or correct what is here, based on newer better info.

In the dark early days when Israel was struggling to become a nation, they managed to get ahold of a few Shermans. Three or so were acquired from the British, probably M4A4s. They also managed to get de-milled Shermans from Junk vendors in Europe. They had to re arm some with an old German 75mm field gun, they were called Sherman (Krupp). When they managed to get ahold of a Sherman armed with a M3 75mm gun the tank was called a Sherman M-3, when it had a 105mm gun, it was a Sherman M-4. As you can see already, naming convention confusion has commenced.

Sherman M1 from the x littlefield collection33
Sherman M1 that used to belong to the Littlefield collection
Sherman M1 from the x littlefield collection
Sherman M1 that used to belong to the Littlefield collection
Sherman M1 from the x littlefield collection2
Sherman M1 that used to belong to the Littlefield collection

In the later fifties Israel was able to get more up to date Shermans. The tanks were M4A1 and M4A3 models with the 76mm M1A1/A2 gun, probably from France. These Shermans were called Sherman M1s, regardless of what motor or hull they had. If they had HVSS suspension, they were called Super Sherman M1. Some of these tanks had an upgraded engines, probably late in their careers, and with Cummings diesels.

The Story gets more interesting, and slightly less confusing in the naming area, when they started to rearm the tanks.

M-50 based on a large hull Sherman, probably an M4A3.
M-50 based on a large hull Sherman, probably an M4A3.
M-50 Sherman based on an early small hatch hull, probably an M4 from the looks of the wheel spacing
M-50 Sherman based on an early small hatch hull, probably an M4 from the looks of the wheel spacing
Another view of the same small hatch M-50
Another view of the same small hatch M-50
Another view of the same small hatch M-50
Another view of the same small hatch M-50

IDF M50 Super Sherman 75mm [LIMITED to 500px]

The M-50: In 1954 Israel and France went to work on a project to fit the excellent French CN 75-50 75mm gun to the Sherman 75mm turret. This gun could shoot an AP round out 3200 feet a second. To fit the gun they added an extension to the front, and rear of the turret, the front one to fit the gun, and the rear one to add counterbalance weight. The first fifty tanks were based on the M4A4 hull that had been converted to use the R975 radial motor. This motor, though less powerful than the A57, was much more numerous, and easy to repair, and the French specialized in this conversion.

These M4A4 hulls with R975 radials still had their VVSS, with 16 inch tracks. The added weight of the new gun on the already larger and heavier hull made for a very sluggish tank with poor off road ability. These early M-50s also had early split hatches on the commander’s cupola. I think these tanks had a loaders hatch installed.

They solved this by installing HVSS, and in many cases a Cummings diesels motor. Once production got rolling, they were installing improved all around vision cupolas and HVSS on all the converted tanks, but some seem to have retained the R975 radial or in rare cases the maybe the Ford GAA? I’ll have to look into this more. One thing is clear from looking at pictures of the tanks in action, and survivors in museums and private collections, is they were not picky about what hull they used, as long as it had a 75mm turret. I’ve seen M4A4 hulls, and other early small hatch hulls in photos, they could be M4, M4A2 or A3, and pictures of a large hatch hulls, that could have been M4 105 tanks, (the only large hatch hull M4 tanks), or M4A3 75 or 105 tanks or even M4A2 75s. I have seen very little evidence that M4A1 hulls were used, I’ve only seen two clear pictures of the M-50 turret on M4A1 hulls, and one was on a non HVSS M4 and you couldn’t see the front of the hull to tell if it was large or small hatch hull.

M51-Isherman-latrun-1
M51 Sherman at the Latrun tank museum
M51 Sherman at the Latrun tank museum
M51 Sherman at the Latrun tank museum
M51 Sherman
M51 Sherman
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M51 at the Kubinka tank Museum Russia

idf-super-sherman-m51hv-isherman

The M-51: In the early 60s the Israelis went to the French for help shoehorning an even bigger gun into the Sherman. They took a shortened version of the 105mm Model F1 gun; this was a modification of the gun used in the AMX-30. The gun retained a stabilizer, I’m not sure if it was the original Sherman one or a more advanced design.  This gun could fling an AP round at 2969 feet a second and had a HEAT round that could penetrate 14 inches of steel.  They chose to use M4A1 76 W tanks exclusively. These tanks had the larger T23 turret and they was helpful in getting the guns to fit. The French prototype retained its VVSS, and R975, but the Israeli production modifications had HVSS and the Cummings diesel fitted to the M-50 models. This was a 950 cubic inch diesel that put out 460 horsepower. This was enough horsepower along with the HVSS, to keep the tanks reasonably mobile, but they were no hotrods.

Both these tanks saw extensive combat use with Israel all the way into the 70s, and then a lot of them were sold off to collectors and museums or used as range targets.

Coming soon! Other stuff the Israelis used the Sherman chassis for!!! 

 

#13 The Suspensions And Tracks: A Smooth And Comfortable Ride Was The Goal, And It Was Achieved, Somewhat

Suspensions and Tracks: It Suspends, and gets laid! 

UPDATE! See the new Suspension and Track pages found here this post will no longer be updated, all the latest info I have will be put on these pages to make it easier to find. 

M4 tanks came with three types of suspension the early VVSS, VVSS and HVSS. The early VVSS suspension system used 16 inch wide tracks. In the link above about Sherman details you can see all the changes the basic VVSS system went through. The VVSS suspension went from the basic two road wheel one return roller with no support module as seen on the Lee, to the later production VVSS bogies that had a bolt on return rollers, that could be bolted to either side of the suspension unit, and sheet steel track supports and much beefier structures that were still usable on either side of the hull. The suspension was one of the parts of the tank that went through so many minor changes, keeping track of them is out of the scope of what this document is meant to do. The Sherman Minutia site does a great job of covering these changes. These changes had little effect on the performance of the tank; think of them more of fine tuning of the basic design for strength, longevity, and ease of manufacture.

What would be the final VVSS, with the return roller that could be swapped to either side, was developed for the M3A4, with the A57 multibank motor. The combo of heavier hull and engine was putting the basic VVSS suspension with the built in return roller under to much stress and causing premature failures. The heavy duty unit was developed to solve this problem was later standardized as the M4 suspension type, though, the bolt on roller and skids would still receive improvements, a beefier skid, and a spacer to lift the return roller, and later a new assembly that raised the return roller higher, the core remained the same. The M3A4 would be the only version of the Lee to receive the heavy duty VVSS suspension units from the factory.

Early VVSS: Using 16 Wide Tracks

vvss early dia

Mid VVSS: Still Using 16 inch Wide Tracks

suspension unit late

vvss suspension broken down
vvss brakedown key
HVSS: The Improved 23 inch wide Track and Suspension System

sherman_bogie_hvss2

 

late VVSS diagram
Late VVSS diagram the whole suspension

The VVSS was later replaced by the HVSS system that had twenty three inch wide tracks, but the suspension was still a bolt on module. It was very well received and used on many late production Sherman models and a few of the variants. It solved the floatation problem of the narrow tracks with few drawbacks.  Thousands of 75mm Shermans received this suspension coupled to large hatch wet hulls. This would become the preferred suspension type for US Army Shermans, and many 75mm hulls either lost the suspension or had its 75mm turret removed and replaced with a T23 turret and 76mm M1A2 gun after the war

Sherman Idler diagram
Sherman Idler wheel parts

This type of system, that could be unbolted, was much easier to work on or fix when damaged than an internal torsion bar suspension or Christie suspensions found on other tanks. Changing the one bogey setup, or even two and putting the track back together was a lot easier than trying to get the stub of a broken torsion bar out of the hull so a new one could go in.

An experimental Sherman with torsion bar suspension was produced and found to be little better than the basic VVSS tanks, and no better than the HVSS tanks and production was never considered. The HVSS suspension made it onto a lot of things built on the Sherman chassis.  HVSS was also retrofitted onto hulls used in Israel’s M51 Super Sherman program.

Tracks:  They are a weapon too you know

 

Click any of the track images for a much larger version.

The Sherman VVSS had at least 14 different types of track, and there was another 4 types for the HVSS. I will cover them in more detail later. Most of the track types were ways to minimize the amount of rubber used in the tracks or to produce an all steel track, as good as the basic rubber and steel T41 track.

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The narrow VVSS tracks limited the Shermans mobility in soft mud, sand, boggy terrain. The Tiger and Panther tanks were better off road than the VVSS Shermans. It’s a good thing they were so rare, and there was a limit to how much mud they could deal with. The mud also accelerated the maintenance problems both these tanks faced and eventually mud got so deep in late 44 no take could go off road much until the ground froze.

 

end connector wear tracktool tracktooluseThe Army came up with a field expedient solution called a “duck bill” end connector. The was an end connector with a sheet steel foot welded to it, when bolted in place on the track it added several inches to the tracks width in soft terrain. The only drawback was they broke off fairly easy, but were easy enough to replace.  This was a very popular and widespread modification, and many little local factories in France were contracted to produce them. They were also factory produced and installed on production Shermans.

Factory Duckbills
Factory Duckbills (image from the Sherman Minutia site.)

 

Sources: TM9-1750K Tracks-Suspension-Turret and Hull Mods M4 series,TM9-731B M4A2, TM9-731G M10A1, TM9-745 GMC M36B2, TM9-748 GMC M36B1, TM9-750M3, TM9-752 M4A3, TM9-754 M4A4, Sherman by Hunnicutt, The Sherman Minutia Site, Son of a Sherman by Stansell and Laughlin