There’s little to no information on this prototype becouse how secret the program was kept, but here is the information i found.
The Komatsu 105GSR was a prototype Designed by Komatsu company in the year 1981 to replace the aging Type 60 SPG. The 105 GSR was a prototype SPG that was armed with an 105mm JSW GSR recoilless gun, also known as the 前進砲. The gun sat in an unmanned turret using the chassi of the Komatsu B78 witch was a IFV prototype that the Komatsu was working on simultaneously with the Komatsu 105GSR program.
Witch was the Komatsu 105GSR competitor prototype, however only one was built and both of the programs was later on cancelled. And the JGSDF choose the Mitsubishi IFV prootype as there new IFV that was later on called Type 89 IFV.
The Komatsu 105GSR had the ability like the Type 74s to tilt its body back and forth, plus the sides thanks to an hydro‐pneumatic suspension system. The same system used in the Type 74s but adapted for a smaller chassi.
There was many reasons for cancelling the program/prototype, but one of the main ones was that the Japanese self defence force considered tank destroyers to be obsolete/relic of the past and was no longer needed by the GSDF. Add the lack of founds to keep the program going left no reason for the program to continue. There were other prototype programs on going at the same time that was more importent for the GSDF like the new MBT they were working on.
The Komatsu 105GSR is using the Cummins VTA-903T engine that has 650 HP, while weighing only 20 Tons and with HP/w ratio of ~23.6. This gave Komatsu 105GSR a top speed of 70 km/h.
- Length: 6.16 meters
- Width: 3.14 meters
- Height (top of the turret): 2.15 meters
- Height (chassis only): 1.155 meters
- Weight: 20 tons
- 105mm JSW GSR recoilless gun
- 7.62 coaxial machine gun
- Stabilizer? Yes
- Top speed: 67 kph
- Engine: Cummins VTA903T
- Engine power: 600 hp
- Power-to-weight ratio: 30 hp/ton
This vehicle can be a fun and a needed addition to the Japanese tech tree, giving players more tanks to fill up there line ups with.