RE: 122 mm HEAT and 152 mm AP-T rounds
I report that in accordance with GOKO decree #3187ss, GAU tested a 122 mm HEAT shell with a V-229 fuse developed by NKV on May 5-7th and a 152 mm AP-T shell with a MD-5 fuse on May 9-10th.
Trials of the 122 mm HEAT shell were performed with the mod. 1938 howitzer and showed the following results:
- Stock propellant charge #4 can be used to fire the HEAT shell.
- At a 30 degree angle, the shell penetrates a 100 mm plate (K~=2400) 70% of the time (out of 10 trials) and at a 0 degree angle, the shell penetrates 100% of the time (out of 4 trials).
- Firing at terrain at 1000 meters shows flawless work of the V-229 fuse (7 trials).
- The precision of the shell when fired at a target 1000 meters away is acceptable: mean deviation of 0.32 m vertically and 0.18 m horizontally.
- During trials, the ballistic cap fell off once, which indicates that it is held on insufficiently well.
- The full stock propellant charge less one bundle of cordite can be used, which achieves a muzzle velocity of 600 m/s.
- The shell penetrates 125 mm of composite armour at an angle of 30 degrees at 1000 meters. The robustness of the hull is satisfactory (4 trials).
- The robustness of the bursting charge after firing at 125 mm armour at normal is satisfactory (2 trials).
- When testing the bursting charge against a 125 mm plate at normal (2 trials) and angled at 30 degrees (2 trials), 3 shells exploded after passing through the plate, one failed to explode (the shell penetrated the armour but no explosion was observed, the shell was found intact without explosive filler).