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The Japanese Ferdinand

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Disclaimer: Yeah naturally Japanese tanks arent a big focus here, so I usually ignore posting things of the matter here. But like the O-I article I posted here oh so long ago, this article comes with the results of some days spent in the archive reading and (continuing to do) translating pages of reports that havent been read in like, decades. So with that said, hope you enjoy. Still a matter I'm unfinished diving into.

 

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Type5 Ho-Ri : The Japanese Ferdinand
 
    As of recently, I've gone through the Japanese National Archive files, looking through to find documents that relate to my studies. While I was there, I stumbled across something that caught my interest. Of said documents, the one of most importance was a file called "Military Secrets No.1". The reports were held by the Ministry of Defense, Army records section, Munitions Mobilization district. Contained in these files were a 3-page production chart of late war tracked vehicles of the Japanese army. Located within the chart I found a number besides the Type 5 Ho-Ri tank destroyer. A vehicle that until recently was only known to have made it to wooden mockup stages. In this lengthy article I will cover my findings on the tank project. Unfortunately visual representations of the tank are still being looked at. So I will use existing found sources for this.
 

 

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National Institute for Defense Studies " Military secret No.1 "

 

 
  In September of 1942, the Japanese Army Staff came to the realization that they had no choice but to design a series of tanks to compete with the arrival of the American Sherman tank. Three concepts were proposed by the Staff, each with their own gun selection; Kou (47mm), Otsu (57mm), and Hei (75mm). As combat data filtered back to Japanese high command, the model Kou concept would later merge with Otsu concept, becoming the basis for the design of the Type4 Chi-To. The Hei proposal would eventually lead to the development of the Type5 Chi-Ri.
 
Additional impetus for new development projects came from a change in the Weapons Administration Headquarters Research Policy in July 1943, a change which was made as a result of analyzing and examining the situation of the tank warfare between the German army and the Soviet Union. Through analysis of this data, the Army's tank doctrine shifted to an emphasis on developing tanks which prioritized the anti-armor mission instead of prioritizing infantry support with limited anti-tank capability. Upon the promulgation of this policy, the Japanese Army decided to develop a series of tank destroyers alongside the medium tanks being designed.
 
As a result, the Type5 Chi-Ri, Japan’s primary medium-tank project, would become the basis for a new anti-armor vehicle. This was a natural choice for IJA command; the Chi-Ri project was more mature. Additionally, it held the most advanced technology Japan produced at the time, technology which would become ubiquitous in the designs that would be made until Japan's defeat in 1945.

 

Chi-Ri.JPG

Testing model of Chi-Ri. Used to trial the series of cannons and turrets designed for the tank. In the photograph it is captured by US forces after the gun had been dismantled for further trials. By Japan's defeat in 1945, three models of Chi-Ri entered production.

 

 

The tank destroyer built upon the chassis of the Chi-Ri would eventually be called the Ho-Ri. Development of this vehicle began shortly after the development of the Chi-Ri, when it had been decided that the tank would use the coil spring suspension system that Japanese manufacturers were already familiar with. After this decision was made, the Army also began work on designing the tank destroyer’s superstructure and casemate. The first design the Army came up with mimicked the Chi-Ri chassis entirely, though the turret was replaced with a reinforced rear-mounted superstructure.
 
The Experimental 10cm Cannon
 
With the development of a new series of tank destroyers taking place, the Army decided to design and produce a new high capacity anti-tank gun to fit the role. On July 22 of 1943, the Army Military Customs Council began designing a 105mm caliber anti-tank gun. Once the design of the cannon had been completed, construction of the cannon took place around a steel shielding that was to be the Ho-Ri's superstructure plating. The trial placement was capable of traversing 10 degrees to the left and the right, elevating by 20 degrees, and depressing by 15. The gun weighed 4.7 tons, with a barrel length of  5.759 m.
 
 During one of the first council meetings that took place on the 30th of June, however, the council gave Major Ota and Lieutenant Colonel Neima  of the Army Weapons Administrative Division, the two chief engineers of the Experimental 10cm project, the task of achieving the requirement that the gun meet 200mm penetration at 600 meters distance and 1000m/s velocity. Naturally, the tank gun was not capable of this, and, instead, the Experimental 10cm had a muzzle velocity of 915m/s with AP (900m/s with HE), and achieved a performance of 150mm penetration at a distance of 1000 meters.
 
The 10cm Experimental Anti Tank gun relied on a system similar to the Type5 75mm Anti tank cannon in relying on an autoloading mechanism for the tank.  This mechanism was known as a semi-automatic loading system, different to the ordinary "autoloader" you see in other vehicles. Unlike the typical autoloading system, the loading crew of the gun system placed the individual shells on the chamber, the system automatically ramming the shell into the breech and forwarding to operation. This gave the effect of automating half the loading routine, as the name suggests. The Experimental 10cm was put into service with the Ho-Ri in 1945. The technical name for the model to be used on the prospective production model was known as the Type5 10cm anti tank cannon.
 
The shell rammer used a horizontal chain closing type, and the automatic loading machine was attached to the back of the gun. It was used because loading ammunition of 123 cm total length and 30 kg weight was deemed too strenuous on a small Japanese physique. Various artillery parts had been diverted and referred to in order to shorten the time of development. The autoloading machine adopted the mechanism of the Type3 12 cm AA Gun for inspiration. The automatic loading mechanism was a continual source of problems, but was repeatedly refurbished to eliminate the drawbacks.
 
 
Capture.PNG
Photograph of the Experimental 10cm Anti tank cannon during trials. Note: The shielf and protector are used on Ho-Ri prototype. Gun was first tested separately and then placed in tank prototype. 
 
Ho-Ri Designs
 
Originally, the Ho-Ri was to keep the secondary 37mm that had been mounted on the Chi-Ri design. The reason for this addition was due to the limited gun-traverse on casemate tank destroyers. Additionally, the primary cannon could only do so much for itself. Hence, to combat many anti tank threats which the Americans could have dedicated to the assault on Japan, the 37mm was seen as being an efficient method of providing additional firepower against infantry and combat vehicles. To this end, the 37mm gun offered a range of APHE and smoke shells. The 37mm was capable of an elevation of 20 degrees and depression of -15 degrees. The mount itself also offered a horizontal traverse of 20 degrees. The 37mm gun could also be used as a ranging device for the main cannon, however this most likely would not have been needed due to the high velocity of the main gun.

 

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Outline of the Ho-Ri design I. Technically entered modified construction of one of the 3 Chi-Ri units.

 

 

The development of the Ho-Ri design was split into two concepts. One being a rear mounted superstructure on the Chi-Ri chassis with a central stationed engine, and the other having a centralized superstructure with a rear engine placement. The Ho-Ri engine selection was different from the traditional diesel that the Army had kept with for most of their tank production. Japan used a BMW designed gasoline V12 aircraft engine . The main reason for this change was due to industrial capacity of Japan reaching its peak, aircraft development was still  a heavy priority and many assets were available for useage. The output of the tank was 550hp/1500rpm.
 
The Ho-Ri II’s design also enabled  the option of adding a 20mm AA station on the rear hatch for additional protection. However, the likelihood of it being useful is up for debate. In addition, central placement of the superstructure enabled 60 rounds for the main cannon to be stored instead of the Ho-Ri I’s 40 rounds. 
 
In terms of armour, both vehicles were to keep the Chi-Ri hull, hence the maximum frontal armour of these tanks was only 75mm. On the superstructure, however, armor thickness was increased to 100mm. By the time both designs, which had been developed in parallel, were presented to Army General Staff it was too late; the war was almost over, and the thickness of the armor was no longer sufficient against US armaments. Nevertheless, the design showed promise. Thus, while neither design was chosen for production, the Ho-Ri I was adopted as the main influence for the third revision of the tank. This third vehicle is commonly labeled as Ho-Ri III. Technically, however, none of the Ho-Ri vehicles were numerically designated. 
 
 
Experimental_Type_5_gun_tank_Ho-Ri_mock-
 
Ho-Ri III wooden mockup.
 
Ho-Ri III took the basis of the Ho-Ri I, and revamped it to fit the needs of the military. The frontal plate of the tank was sloped at a 70 degree angle and increased to 120mm thickness. In this configuration, the tank was capable of withstanding most anti tank measures the Unites States could bring to the home islands of Japan. The designers of the tank built a wooden mockup form of the revision 3 design and presented it to the general staff, at an unknown date. The Ho-Ri kept its general composition the same as the prior designs, but this change was what the Army Staff ultimately decided to go with and schedule the Ho-Ri for prototype construction. The tank would have a crew total of 6; driver, gunner, two loaders, radio operator, and commander. The past designs made use of the 37mm that the Chi-Ri hull had present, however, with the chosen slope change on the Ho-Ri III, this was no longer present and a crew member spot was open. The 6th crew member was placed as the second loader to assist with the autoloading mechanism and provide shells for the primary loader.
 
The construction of the prototype was completed in 1944. The tank achieved a speed of 40kmh during the trials. The tests were seen as a success, resulting in the Army ordering 5 units of the tank. The tank was put in service as the Type5 Ho-Ri, as the production model started in 1945. However, by the time of the war's end, the series of tanks only made it to 50% completion. Only one operable prototype had been completed fully. Reports of the trial are still being processed at this time [11/15/16].
 
My research continues. I have been spending days now trying to go through everything and get the details of the tank out to the light. Once all the documents are collected together and  organized, translated, and put back together I will write a follow up article to this.
 
 
You can view full post with all images on my blog post:
 

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So the Ho-Ri was actually designed after the Ferdinand based on its(god awful) debut at Kursk and not a case of convergent design evolution? I sorta assumed the later

 

Not quite. The tank never used the German designs as influence. The title is simply out of the resemblance of the two vehicles. 

 

 

As far as using the same doctrine as the Germand and Soviets goes, it was purely a purpose motive. Not a design approach. 

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So it's a 120 mm thick steel plate sloped at 70°? That is overkill for WW2 and even for the next twenty years after that. Or is it only 120 mm at the line-of-sight? Did the superstructure armor remained unchanged?

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So it's a 120 mm thick steel plate sloped at 70°? That is overkill for WW2 and even for the next twenty years after that. Or is it only 120 mm at the line-of-sight? Did the superstructure armor remained unchanged?

Yes. The files say maximum armour thickness at the front is a 120mm plate. How successful they were at it is up for wild guesses.

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What other TDs does Japan have?

Japanese tank destroyers are split between assault guns and gun tanks. Ones of popular mention are the Na-To series (30 produced). The others are mainly assault guns using the chi ha chassis and the alike.

There is also the Ka-To. Which like the Ho-Ri is the project based off the new doctrine. Instead of Chi-Ri it uses Chi-To chassis as the base. Only one prototype, never made it to production numbers.

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      Sources:
       
       
      https://www.docdroid.net/gDMQra3/raiden-aeroplane-february-2016.pdf#page=2
      F6F-5 vs. J2M3 Comparison
      http://www.combinedfleet.com/ijna/j2m.htm
      http://www.wwiiaircraftperformance.org/japan/Jack-11-105A.pdf
      https://babel.hathitrust.org/cgi/pt?id=mdp.39015080324281;view=1up;seq=80
      https://archive.org/stream/corporationrepor34unit#page/n15/mode/2up
      http://users.telenet.be/Emmanuel.Gustin/fgun/fgun-pe.html
      http://ww2data.blogspot.com/2016/04/imperial-japanese-navy-explosives-bombs.html
      https://www.pacificwrecks.com/aircraft/j2m/3008.html
      https://www.pacificwrecks.com/aircraft/j2m/3013.html
      https://www.pacificwrecks.com/aircraft/j2m/3014.html
       
       
      Further reading:
       
      An additional two dozen Raiden photos: https://www.worldwarphotos.info/gallery/japan/aircrafts/j2m-raiden/
       
       
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      In other cases though, the paper tiger is created post-facto, through the repetition of sloppy research without consulting the primary documents.  One of the best examples of a paper tiger is the Tiger tank, a design which you would think was nearly invincible in combat from reading the modern hype of it, but in fact could be fairly easily seen off by 75mm armed Shermans, and occasionally killed by scout vehicles.  Add to this chronic, never-solved reliability problems, outrageous production costs, and absurd maintenance demands (ten hours to change a single road wheel?), and you have a tank that really just wasn't very good.
       
      And so it is time to set the record straight on another historical design whose legend has outgrown its actual merit, the British EM-2:
       

       
      EM-2ology is a sadly under-developed field of study for gun nerds.  There is no authoritative book on the history and design of this rifle.  Yes, I am aware of the Collector's Grade book on the subject.  I've actually read it and it isn't very good.  It isn't very long, and it is quite poorly edited, among other sins devoting several pages to reproducing J.B.S. Haldane's essay On Being the Right Size in full.  Why?!!?!!
       
      On top of that, there's quite a bit of misinformation that gets repeated as gospel.  Hopefully, this thread can serve as a collection point for proper scholarship on this interesting, but bad design.
       
      Question One:  Why do you say that the EM-2 was bad?  Is it because you're an American, and you love trashing everything that comes out of Airstrip One?  Why won't America love us?  We gave you your language!  PLEASE LOVE ME!  I AM SO LONELY NOW THAT I TOLD THE ENTIRE REST OF EUROPE TO FUCK OFF.
       
       
      Answer:  I'm saying the EM-2 was a bad design because it was a bad design.  Same as British tanks, really.  You lot design decent airplanes, but please leave the tanks, rifles and dentistry to the global superpower across the pond that owns you body and soul.  Oh, and leave cars to the Japanese.  To be honest, Americans can't do those right either.
       
      No, I'm not going to launch into some stupid tirade about how all bullpup assault rifle designs are inherently a poor idea.  I would agree with the statement that all such designs have so far been poorly executed, but frankly, very few assault rifles that aren't the AR-15 or AK are worth a damn, so that's hardly surprising.  In fact, the length savings that a bullpup design provides are very attractive provided that the designer takes the ergonomic challenges into consideration (and this the EM-2 designers did, with some unique solutions).
       
      Actually, there were two problems with the EM-2, and neither had anything to do with being a bullpup.  The first problem is that it didn't fucking work, and the second problem is that there was absolutely no way the EM-2 could have been mass-produced without completely re-thinking the design.
       
      See this test record for exhaustive documentation of the fact that the EM-2 did not work.  Points of note:
       
      -In less than ten thousand rounds the headspace of two of the EM-2s increased by .009 and .012 inches.  That is an order of magnitude larger than what is usually considered safe tolerances for headspace.
       
      -The EM-2 was less reliable than an M1 Garand.  Note that, contrary to popular assertion, the EM-2 was not particularly reliable in dust.  It was just less unreliable in dust than the other two designs, and that all three were less reliable than an M1 Garand.
       
      -The EM-2 was shockingly inaccurate with the ammunition provided and shot 14 MOA at 100 yards.  Seriously, look it up, that's what the test says.  There are clapped-out AKs buried for years in the Laotian jungle that shoot better than that.
       
      -The EM-2 had more parts breakages than any other rifle tested.
       
      -The EM-2 had more parts than any other rifle tested.
       
      -The fact that the EM-2 had a high bolt carrier velocity and problems with light primer strikes in full auto suggests it was suffering from bolt carrier bounce.
       
       
      As for the gun being completely un-suited to mass production, watch this video:
       
       
       
      Question Two:  But the EM-2 could have been developed into a good weapon system if the meanie-head Yanks hadn't insisted on the 7.62x51mm cartridge, which was too large and powerful for the EM-2 to handle!
       
      Anyone who repeats this one is ignorant of how bolt thrust works, and has done zero research on the EM-2.  In other words, anyone who says this is stupid and should feel bad for being stupid.  The maximum force exerted on the bolt of a firearm is the peak pressure multiplied by the interior area of the cartridge case.  You know, like you'd expect given the dimensional identities of force, area and pressure, if you were the sort of person who could do basic dimensional analysis, i.e. not a stupid one.
       
      Later version of the British 7mm cartridge had the same case head diameter as the 7.62x51mm NATO, so converting the design to fire the larger ammunition was not only possible but was actually done.  In fact, most the EM-2s made were in 7.62x51mm.  It was even possible to chamber the EM-2 in .30-06.
       
      I'm not going to say that this was because the basic action was strong enough to handle the 7x43mm, and therefore also strong enough to handle the 7.62x51mm NATO, because the headspace problems encountered in the 1950 test show that it really wasn't up to snuff with the weaker ammunition.  But I think it's fair to say that the EM-2 was roughly equally as capable of bashing itself to pieces in 7mm, 7.62 NATO or .30-06 flavor.
       
       
      Question Three:  You're being mean and intentionally provocative.  Didn't you say that there were some good things about the design?
       
      I did imply that there were some good aspects of the design, but I was lying.  Actually, there's only one good idea in the entire design.  But it's a really good idea, and I'm actually surprised that nobody has copied it.
       
      If you look at the patent, you can see that the magazine catch is extremely complicated.  However, per the US Army test report the magazine and magazine catch design were robust and reliable.
       
      What makes the EM-2 special is how the bolt behaves during a reload.  Like many rifles, the EM-2 has a tab on the magazine follower that pushes up the bolt catch in the receiver.  This locks the bolt open after the last shot, which helps to inform the soldier that the rifle is empty.  This part is nothing special; AR-15s, SKSs, FALs and many other rifles do this.
       
      What is special is what happens when a fresh magazine is inserted.  There is an additional lever in each magazine that is pushed by the magazine follower when the follower is in the top position of the magazine.  This lever will trip the bolt catch of the rifle provided that the follower is not in the top position; i.e. if the magazine has any ammunition in it.
       
      This means that the reload drill for an EM-2 is to fire the rifle until it is empty and the bolt locks back, then pull out the empty magazine, and put in a fresh one.  That's it; no fussing with the charging handle, no hitting a bolt release.  When the first magazine runs empty the bolt gets locked open, and as soon as a loaded one is inserted the bolt closes itself again.  This is a very good solution to the problem of fast reloads in a bullpup (or any other firearm).  It's so clever that I'm actually surprised that nobody has copied it.
       
      Question Four:  But what about the intermediate cartridge the EM-2 fired?  Doesn't that represent a lost opportunity vis a vis the too powerful 7.62 NATO?
       
      Sort of, but not really.  The 7mm ammunition the EM-2 fired went through several iterations, becoming increasingly powerful.  The earliest versions of the 7mm ammunition had similar ballistics to Soviet 7.62x39mm, while the last versions were only a hair less powerful than 7.62x51mm NATO.
       
      As for the 7mm ammunition having some optimum balance between weight, recoil and trajectory, I'm skeptical.  The bullets the 7mm cartridges used were not particularly aerodynamic, so while they enjoyed good sectional density and (in the earlier stages) moderate recoil, it's not like they were getting everything they could have out of the design.
       

      note the flat base
       
      In addition, the .280 ammunition was miserably inaccurate.  Check the US rifle tests; the .280 chambered proto-FAL couldn't hit anything either.
    • By Jagdika
      All photos were taken by myself in year 2016 during my visit to Beijing. Tanks are from the Military Museum of the Chinese People's Revolution and the Tank Museum(currently closed). Enjoy.
       
      No.1: Type 94 Light armored car (Tankette) in the Tank Museum
       





       
      This is the early version of the Type 94 Tankette. It was found in a river in 1970s. It is the best preserved Type 94 Tankette in the world.
       
      No.2: Type 97 Medium Tank in the Tank Museum
       




       







      This is a late version Type 97 medium tank. It carries the old small 57mm gun turret but has the revised engine ventilation port. This tank was donated by the Soviet 7th mechanized division  before they withdrew from China in 1955.
       
      No.3: Type 97 Medium Tank Kai in the Military Museum of the Chinese People's Revolution
       

       


       
       
       
        This Type 97 Medium Tank Kai's combat serial number is 102. It belonged to the former China North-East tank regiment. It took part in the attack of Jinzhou against KMT army on 1948-9-14, and did great contribution for knocking out their bunkers and MG nests by shooting and ramming. Thus after the battle this tank was awarded with an honored name:"The Hero(功臣号)“ About the tank itself, it was assembled by the Chinese army themselves by using destroyed or damaged Chi-Ha parts after the surrender of Japan. This particular tank was built up with a normal Type 97's chassis(57mm gun version) early model, and a Type 97 Kai's Shinhoto(New turret for the 47mm gun). However there are other saying claim that this tank was modified by the Japanese. It was the first tank that roared over the Tiananmen Square during the Founding Ceremony of China on 1949-10-1.
       
       

      The same tank on 1949-10-1. China's tank army origins from old IJA tanks.
       
      No.4: Type 97 Medium Tank in the Military Museum of the Chinese People's Revolution
       

      Sorry, only one photo was taken. This Type 97 Medium Tank has a chassis from Type 97 Medium Tank Kai and a turret from a normal Type 97 Medium Tank. It was merged together by the Chinese army.
       
      No.5: Type 95 Armored Track(Train track) Vehicle in the Military Museum of the Chinese People's Revolution
       



       
      Only two samples survived. One is in China here and one is in Kubinka, Russia (Maybe now it is transfered to the Patriot Park? I don't know).
       
       
      Hope you enjoy the photos I took! No repost to other places without my permission.
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