"Brief report on the results of experimental, scientific research, and test production at VNII-100 in June of 1950
Topic #1: heavy ISU-130 SPG on the chassis of the new heavy tank
The development of the ISU-130 (Object 263) technical project was completed in June of 1950.
Two sets of overall blueprints and detailed blueprints of specific components as well as an explanatory memo were sent to the Ministry of Transport Machinery with letter #1035ss on June 28th, 1950.
To resolve issues connected with the development of the technical project by the Institute as of July 1st, 1950, the following experimental work was performed.
- An electric drive for the KPV AA machine gun mount was investigated and tested with the goal of determining the minimum stable aiming speed, range of adjustment for the drive, as well as speed characteristics in conditions when the aiming rate does not depend on the load.As a result of the trials, an electrical diagram was designed that allows stable aiming of the AA KVP mount at a speed as low as 0.05 degrees per second, a range of adjustment of over 1200, and speed characteristics that are independent of the load.
- A synchronization system between the gun and sight when the electric gun elevation drive is used. This topic included the following subtopics:
- Development, production, and trials of a sight servo motor that could aim at a minimal speed of 0.04 degrees per second.
- Development, production, and trials of a servo for the synchronized drive and calculation of its stable zeros.
- Composition of an overall diagram of a synchronized tracking drive at the laboratory on a stand and preliminary adjustments of the system.
- Installation of the system on the Object 263 vehicle, adjustments, and firing trials of the synchronized gun sight.Trials of the synchronization system showed that the system that was developed is functional and compensates for the difference without oscillation. Trials against a target at 25 meters gave the same results as with a rigidly connected sight.Trials with the coaxial KPV machine gun at 1300 meters showed the following results:
- Electrically synchronized sight: 25 hits out of 50 shots, 36 hits out of 50 shots.
- Rigidly linked sight: 32 hits out of 50 shots, 49 hits out of 50 shots.
- Development, production, and laboratory testing of the tilting apparatus.Trials showed that the tilting apparatus is activated at a tilt of 8-9 degrees and deactivated at a tilt of 5-6 degrees.Damping in the tilting apparatus allows the electric drive to be enabled or disabled within 1.5 seconds, which is enough to ensure that tilting of the hull will not affect the tilting apparatus.Presently the tilting apparatus with a stepping multiplier is installed on the Object 260 vehicle for mobility trials.VNII-100 has produced a 1:10 scale model of the vehicle in order to defend the technical project. Production of a 1:1 scale model at the Leningrad Kirov factory has been expedited. "