The experimental ammunition bins for 76 mm rounds on the floor of the fighting compartment of the T-34 tank:
- Allows for easier access and increases aimed rate of fire to 4 RPM versus 2 RPM with the existing racks.
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Oh I didn’t even notice that part.
They also say at the bottom:
Practical rate of fire on the move from short stops: 3 RPM.
Task 4 and 5 are show short stop results.
The fastest time was 11 seconds. The average time, not counting the situations where they had missfires and trigger faults (so a total of 5 stops counted), is 14.8 seconds from task 4.
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They fired 2 shots on each stop, they corrected for fire at 1.5 kilometers. 12 stops with 24 rounds fired
Practical rate of fire on the move from short stops: 3 RPM.
Is from 9 mins 25s / 24 rds & 5 mins 2s for 16 rounds. It’s a calculation of the total drill time, which is why the time you found (15s) contradicts the conclusion.
The “experimental racks” topic was removing the older ammo storage solution used in T-34.
Initially they came in “suitcases” which took an inordinate time to load into the tank, and were awful to use, since you’d have to rip them open every few rounds.
I had actually missed that part about it being 2 shots, which is my bad. I fully admit my mistake there.
As far as I can tell, you’re getting 5.5 seconds by taking the fourth stop time, which was 11 seconds, and dividing it by 2.
That means that they stop the tank, load a round, fire, then load another round, and fire again, according to your calculation.
You’re making the assumption that the gun was unloaded when the tank stopped. From what I’ve read, this is simply erroneous. Both tank-archives and the report that is linked in that blog state that:
The tank was stopped when the gun was ready to fire.
And from the actual report (translated):
The tank stopped when the artillery system was ready to fire.
In other words, the gun would be already loaded, then the tank would stop, fire, correct the aim, and after the cannon is loaded again, fire once more.
So as far as I can tell, the 11 second value is still just for one round, and with the specific testing procedure it seems that the loader would be capable of lap loading, as he can already have a round at the ready when the gun fires for the first time.
This also mean that the RPM of 3 isn’t inherently errouneous. The time that isn’t spent specifically doing the short stops is spend loading the very first round and accelerating the tank. Keep in mind that my “15 seconds” I calculated were explicitly without taking into account all the short stops where there were missfires. I explicitly say that I only counted the 5 specific situations where nothing “bad” happened.
11 seconds for 2 aimed shots != they reloaded in 5.5s.
From:
Time spent aiming, firing, and waiting for gun to recoil is 4.1s per shot.
Counting bad ammunition into the firing cycle isn’t a concession, it’s unreasonable.
I don’t think you understood my comment.
I’m explicitly stating that 5.5 seconds of fastest reload speed, which is what you stated, can only be achieved if you don’t read the document fully, and that it is not actually the fastest reload speed that was achieved.
Even factoring in the 4.1 seconds you state here (which is from the IS-3 in a completely separate test in different conditions), the 11 seconds of the T-34-76 goes down to 7 seconds, not 5.5.
If the average time to aim and fire a single shell is 4.1s, and we assume he only loads the second round.
Then 8.2s in each drill is spent aiming and cycling the gun.
Yeah, in this test it was -8*C and the target was obscured with snowfall.
The tests are stating the “practical rate of fire”.
If the gun is unreliable, then it is unreliable. Not accounting for it when trying to give your soldiers the actually practical rate of fire that they will on average achieve is way more incorrect then it is correct.
- The firing pin does not guarantee ignition of the primer.
- The lubricant on the trigger mechanism spring guide rod freezes at a temperature of -8 degrees, which delays the movement of the worm gear and delays firing.
- The PT-6 sight is quickly covered in snow which reduces visibility and increases the time to fire.
At this time the red army still conducted testing with WW1 era stocks of HE shells. And this is L11 gun so unrelated to F-34.
Let’s take the average of 15s you gave, -8.2s shows ~6.8s reload, which is comparable to PT-76, which, although it has many more ready rounds, presents the same conditions for the first few shells.
None of this changes the fact that neither the maximum reload rate nor the average reload rate that was achieved in this test was 5.5 or ~8 seconds like you had claimed.
Even assuming that it is a 4.1 second delay for recoil, reaiming the gun and such, you still get a maximum of 7-8 seconds, and an average (without issues) of 11 seconds.
And again, that’s not mentioning the fact that the entire test configuration when firing on the *short stops allows for lap-loading, as the gun is already loaded from the get go.
4.1s per shell, 2 shots fired per stop. 8.2s on average.
So you haven’t proven lap loading but it must happen because it’s impossible for a T-34 76, to have a reload of… A PT-76?
Are you purposefully ignoring the part where both the blog and the actual report state that the gun is already loaded when the tank stops?
You failed to read.
If the gun is loaded when the tank stops the procedure is;
Aim and fire 1 round, 4.1s
Load 2nd round X time
Aim and fire 2nd round, 4.1s
I neglected removal of brass. Obviously, because snowfall obscured sight and target, the time to aim is likely longer than IS-3 trial.
The time is counted from the command “fire” to the last shot. The gun is aimed after every shot.
There is no aim correction for the first shot.
Secondly, not only do the 4.1 seconds come from the IS-3, and not the T-34-76 with a much weaker gun and far easier to traverse turret, part of those 4.1 seconds is specifically waiting for recoil, which is not counted after the second shot is fired.
If the tank moves 350 meters for 12 short stops, how is it supposed to hit a target without correcting aim? And in snowfall, where the sight is obscured?
You are arguing the T-34 76 has a shorter aiming cycle than the IS-3?
and the recoil brake returning the gun to the firing position (1 second). A terrible tragedy to be sure.
What you’re talking about, fire without correcting aim, is a different metric. You’re interpreting the text to get to a fixed conclusion.
Here’s combat experience:
From the 76 mm gun it is 16-17 RPM. In a cohesive crew the radio operator can help hand ammunition into the turret without being distracted from his work.
There is something that makes me doubt. It also states the RPM of the 45mm cannon at 3-4 RPM, something that seems extremely long to me for a cannon of that type.
I’m pointing out that the aim time isn’t added twice in each short stop.
After firing the second shot, the time count stops as explicitly stated by the report, which says that the time is counted from “fire” until the last shot. Afterwards the gun is reloaded and more than likely the gun is adjusted.
The only time the gun is adjusted and it is timed is after the 1st shot.
The practical rate of fire of the 45 mm gun is 3-4 RPM
The most common problems with the 45 mm gun is misfires
Problems with 45mm HE shell, T-70 already has a poor shooting rate to begin with, and clearing misfires makes it unmanageable.
In real life, the 45mm gun fires a 2.15 kg HE shell at 340 m/s velocity, it’s an exceptionally good HE shell for the caliber, leading to the 45’er being used as an informal infantry gun, but it can be finicky
But later it’s pretty obvious what we’re working with.
Usage of the ammunition in the tank depends on the conditions. There were cases where all ammunition was expended in 20-25 minutes.
Which is 100 rounds over 20-25 minutes, while searching for targets.
Now, you might notice that’s 4-5 r/m in combat against infantry or similarly hard to detect targets for 100 rounds. Which is slightly faster than the normal preconception might indicate, is possible.
Yes, as you can imagine they are talking exclusively about the 45mm cannon on the T-70, which only has two crew members. Now I do see the point, since it is the time between ``finding the target-loading-locking-shooting-and starting over´´, since several shots at the same target would make the reload time shorter.
These are the problems of tanks with few crew members, having few eyes made it take longer to locate, aim and reload. That is why tanks ended up carrying three crew members in the turrets.