At the beginning of the second world war, the standard Japanese medium tank, the Type 97 Chi-ha had become completely obsolete because lower than its contemporary adversaries on the Allies side, even the light tank M3 Stuart. The weak swiftness of its short gun of 57 mm could not penetrate the shielding of the enemy tanks whereas the vulnerability of its own shielding to the enemy guns was extremely large. In order to replace the type 97, a whole series of medium tanks were developed by the Japanese: the first of the list being Type 1 Chi-He.
Chi-He made its appearance in 1941 but its production did not begin before 1943 because of the little interest caused by the tanks near Japanese Imperial army. A total of 170 specimens were built by Mitsubishi J and Sagami RZ in 1943-1944. These tanks remained in Japan to defend the archipelago and thus were never seen into the combat before the intervention of the atomic bomb. However some Type 1 were used by the 2nd Division during the battle of Leyte in Philippines during the last moments of the war in the Pacific.
Type 1 was slightly larger than the Type 97 and was equipped with a thicker frontal shielding,assembled by weldings and either by rivets. It was propelled by a diesel engine Mitsubishi Type 100 developing 240 hp in order to compensate the increase in the shielding and thus in the weight. Type 1 was armed with a gun of 47 mm Type 1 with high velocity, equipped of a barrel of 2.25 m and an initial muzzle velocity of 810 m/s. This swiftness got for Type 1 a capacity of penetration of shielding of 55 mm to more than 100 m and of 30 mm to more than 1000 m, which represented more of the double of the performances of the short gun of the Type 97 Chi-ha. In spite of these improvements, Type 1 of 47 mm was always ineffective against the Alliés shieldings in 1941.
The gun took place in a triplace turret lately conceived which provided space for the integration of a loader. Let us note that this turret also equipped the Type 97 Shinhoto (new turret) Chi-ha and the Type 3 Ka-Chi Amphibian.
Although higher than the Type 97 Chi-ha and also than the Type 97 Shinhoto Chi-ha, Type 1 Chi-He remained well in low of the capacities of protection and destruction of the standard American medium tank, M4 Sherman.
An anti-aircraft version, Type 1 Ta-Ha, equipped with a gun of 37 mm anti-aircraft in the place of the gun of 47 mm was designed but never started production.

接下来是Type-3坦克
Type 3 Chi-Nu Medium Tank


The medium tank Type 3 Chi-Nu was especially designed to thwart M4 Sherman American. The Technical Office worked already on another medium tank, the Type 4 Chi-To with a same aim but the delays and the problems in the development required the development of a simpler solution and more rapid to be realized. The development of Chi-Nu started in May 1943 and was finalized in October of the same year. The little interest of Japanese staffs for the tanks delayed the setting in production until in 1944. Moreover American bombardments caused great shortages on equipment and materials supply.
The Chi-Nu was produced at 166 specimens in 1944-1945. The Chi-Nu one was the last tank brought into service by the Japanese army. The Chi-Nu used the same hull that Chi-He but was equipped with a new three-seater turret accomodating the gun of 75 mm Type 3 L/38.4 (2.88 m long barrel). This gun had an initial muzzle velocity of 680 m/s and a capacity of penetration of 90 mm to more than 100 m and of 65 m to more than 1000 m. This gun was developed starting from the gun of 75 mm Type 90 based on the French mountain gun of 75 mm Schneider 1919.
Type 3 remained in Japanese archipelago to push back American invasion projected in 1945. They were versed in 6 regiments (the 3rd and 4th armored division) on Kyushu and Honshu. Japan capitulated before American terrestrial invasion and thus, the Type 3 Chi-Nu was never used into the combat.

1式坦克图表


表格里写到产量是587，但是本人对照简氏和鱼鹰社都写着1943年生产15台，44年155台共170台，这里不知计算口径究竟如何差异这么大，目测掺了些97改进去。

Type-3 Chi-Nu


同样的，鱼鹰社和简氏给出的1944-45年产量合计55+89=144台。与一式最大区别是换装了威力更强的75mm 3式L/38火炮。顺带一提为了装上这门炮，没有塞进同轴机枪，所以武器装备一栏里7.7mm机枪仅一挺。

以下是75mm级以下口径日本火炮的穿深

同口径穿深水准次于其它主要交战国家。以3式战车的75mm Type3L/38的1000m/65mm的水平，不及德国的Kwk40L/43(废话)
个人认为只看尺寸、火力，1式、3式中型战车比较接近德国3~4年前的III号早、中、后期的系列型号，3式的火力也许胜出一些。而III号在速度和防护方面是要高出。