Tuesday 16 April 2019

T-44 Prototype #2 Rate of Fire Trials

"Results of firing

Firing from standstill at an angle of 0 degrees. 

Target
Range
# shots
# direct hits
# of hits within 30 meters
Time spent
Rate of fire
Notes
Panther. Aiming was done using manual traverse.
900
10
8
2
1 min 5 sec
9.2 RPM
All rounds in turret rack
Panther and PzIII in a 30 deg arc. Aiming was done using manual traverse.
800
5
5
-
1 min 25 sec
7 RPM
5 rounds in the turret rack, 5 rounds to the right of the driver
1000
5
5
-
Panther tank, PzIII tank, 3x3 meter target in a 40 deg arc. Aiming was done using manual traverse.
800
3
3
-
1 min 40 sec
5.4 RPM
All rounds stored to the right of the driver
1000
3
3
-
1500
4
4
1
Panther tank, PzIII tank, 3x3 meter target in a 40 deg arc. Aiming was done with electric traverse.
800
5
5
-
2 min 40 sec
3.7 RPM
1500
5
1
2


The maximum aimed rate of fire of the 85 mm ZIS-S-53 gun from standstill firing at one target is 9.2 RPM. The maximum aimed rate of fire at two or three targets is 5-7 RPM. The precision attained during the measurement of rate of fire was good.

The relatively low aimed rate of fire obtained when using the electric traverse is explained by the fact that it is inconvenient to move from the hand to the electric traverse, and that the latter turns the turret at a very high speed.

Determining the maximum rate of fire

The maximum rate of fire was determined in the following conditions:

  • The ammunition is placed in ammunition racks.
  • Time spent on firing was measured from the "Load" command to the last shot fired.
  • The firing was done in groups of 10 without adjusting aim.
  • The T-44 tank was placed at 0, +90, -90, and 180 degrees to the target.
Angle of the tank
Number of shots
Location of ammunition
Time spent
Rate of fire
0
5
Turret bustle
28 sec
10.7 RPM
0
5
Right of driver
31 sec
9.7 RPM
+90
5
Right of driver
60 sec
5 RPM
-90
5
Right of driver
54 sec
5.3 RPM
180
5
Right of driver
72 sec
4.1 RPM
The maximum unaimed rate of fire at an angle of 0 degrees to the target is 10 RPM.
The maximum unaimed rate of fire at angles of +90, -90, and 180 degrees to the target is 4-5 RPM.

Effectiveness of firing on the move

The precision and rate of fire of the 85 mm ZIS-S-53 gun on the T-44 tank in motion was tested in the following way:
  • The ammunition is placed in ammunition racks.
  • Time spent on firing was measured from the "Load" command to the last shot fired.
  • Adjusting for distance was done by moving the sight point in relation to the target.
  • Firing was done at one or two targets in groups of 5.
  • Aiming was performed using manual traverse.
Targets:
  • PzIII tanks at a range of 1000 meters
The angle of the tank to the target was 0 degrees. The speed during firing was 9-12 kph. Aim was adjusted after every shot.

Target
Range to target
Number of shots
Number of direct hits
Number of hits within 30 meters
Number of hits within 100 meters
Time spent
Rate of fire
PzIII tank
600-800 meters
10
2
1
2
2 min 13 sec
4.5 RPM
PzIII tank #1
PzIII tank #2
600-800
800-1000
5
5
1
-
-
1
1
1
2 min 20 sec
4.3 RPM

The aimed rate of fire of the 85 mm ZIS-S-53 gun obtained when firing on the move with the manual traverse when firing at one or two targets, 4.4 RPM, is low, due to effort spent on aiming, inconvenience of using the electric firing mechanism when also using the elevation mechanism.

The precision of the gun, 25% direct hits and hits within 30 meters, is low, due to frequent and severe oscillations of the tank (the suspension was broken, the rear torsion bar was broken and 5 wheels were missing rubber rims). 

Aimed firing using the electric traverse is difficult due to the speed of the turret traverse."

2 comments:

  1. Was the suspension this beat up before they started the trials, or was it damaged during the trials?

    What does the specific use of "suspension" mean, as opposed to torsion bar? Was in of the arms carrying a road wheel broken?

    ReplyDelete
    Replies
    1. The torsion bar was the item that was broken.

      Delete