39 replies to this topic

[ApocSurvivor713]

Is there anything historically to explain in game derp guns' low rate of fire?  As in, why can't the Hetzer's 105 fire as quickly as the S35's 57?  The loader is doing essentially the same thing for both guns, right?  Did real-life derp guns have a low RoF, or is this mainly for game balance?

[skorpion777]

ApocSurvivor713, on Apr 07 2012 - 00:29, said:

Is there anything historically to explain in game derp guns' low rate of fire?  As in, why can't the Hetzer's 105 fire as quickly as the S35's 57?  The loader is doing essentially the same thing for both guns, right?  Did real-life derp guns have a low RoF, or is this mainly for game balance?

120mm on an Abrams tank can be reloaded in 4 seconds in the loader gets it right. WW2 M4 Sherman loader can load up a 75mm in 4 if he gets it right, but then again, i'm not an expert. I think its for game balance but don't quote me on it.

[WontEndWell]

Mostly it's for game balance, but there was a historical factor. Some tank compartments didn't allow for quick loading, and shells of different sizes weighed more, so took longer to grab and load, and on top of that some guns used a two part shell system where there was a shell and a propellent charge (Generally for your larger guns and "derp" cannons.).

Just a general educated guess on my part.

[Magormor]

prob balance, and shell weight.  Think about it if its heavier and larger it takes more time to load.

[HBK22578]

game balance but u must also keep in mind the size of the rounds that derps fired, for example the KV (KV-2) derp gun...very large ammo, very heavy ammo

[Hellseer]

Well, I don't see how some shells took minutes to load. Even Arty crews could get the load pretty quickly. So obviously it's for game balance.

I just wish HE was more reliable. I don't know about other people, as I've only used it here and there a few times. But I could shoot the same place twice on the same tank(Same spot, accuracy not withstanding) and get two different results.

[kllp101]

I would say historical accuracy and gameplay. KV derps took much longer because.. well, Im not so sure. But I can guesstimate that the weight of shell, the aiming time, the secure of the gun, would definitely slow down reload times. Think, a 152mm shell is quite heavy. And the bigger the shell, the more tougher the gun needs to be. Im pretty sure they had latches to make sure the shell was fired correctly. Also, the number of loaders significantly affects the loading time. A tank generally has at least 2 loaders if its a heavy tank. A arty crew of 5 or more may use all of their crew for loading, maybe 1 for recon. So arty definetely has a loading speed advantage because to fire, they must be stationary (most are) and if they are stationary, a driver may help out with the loading process . Might do some research on derps in the future but some interesting stuff, good thread  .

[Sabertoothpython]

I have been looking 20 min for the picture, but cant find it...

Theres one out there that shows the IS tank's 122mm round beside 1 of the crew members (outside the tank). Thing is at least 4 feet long. And the weight would be immense. Try lifting a modern standard 120mm round.

All and all, it makes sense. A 37mm for example, you can hold 2 at a time and feed quickly. A 150mm is a fight to load

[Thenoob1234]

Certain shells were larger, or used differing materials, and as such weighed more. In addition, some shells used two-part systems which would require a lot more time to load. Other different types of Shells, such as HE or AT rounds, required a fuse charge and weighed more. Of course, the amount of loaders would significantly reduce or increase the loading time. Two loaders would be twice as fast as a single loader. Lastly, larger caliber guns required to be fired absolutely correctly, as a mistake in firing the shell could cause the tank to explode.

[DanQuayle]

Hellseer, on Apr 07 2012 - 00:45, said:

Well, I don't see how some shells took minutes to load. Even Arty crews could get the load pretty quickly. So obviously it's for game balance. I just wish HE was more reliable. I don't know about other people, as I've only used it here and there a few times. But I could shoot the same place twice on the same tank(Same spot, accuracy not withstanding) and get two different results.

Keep in mind that a field artillery crew is working out in the open and providing long range indirect fire support behind the lines.  A tank crewman has to do his work in a confined space, and crew ergonomics were usually an afterthought in WW2 AFV designs, especially Soviet tanks.  Add to that the smoke, the darkness, the noise and the fact that a tank crew using its gun is right in the thick of things, it's no surprise RPMs would suffer.  IIRC the most common field pieces deployed by the Red army were 76, 122, 152 and, occasionally 203mm field guns/howitzers.  The 122 on the IS-2 & SU/ISU-122 and the 152 on the SU/ISU-152 were just modified howitzers, so the crews had to do essentially the same work as artillerymen, only in a noisy, dark, smoky steel coffin.

Totally agree with you on HE consistency, though.  We can dream, can't we?  

Sabertoothpython, on Apr 07 2012 - 01:02, said:

I have been looking 20 min for the picture, but cant find it...Theres one out there that shows the IS tank's 122mm round beside 1 of the crew members (outside the tank). Thing is at least 4 feet long. And the weight would be immense. Try lifting a modern standard 120mm round. All and all, it makes sense. A 37mm for example, you can hold 2 at a time and feed quickly. A 150mm is a fight to load

I think I've seen the picture you're referring to, unfortunately I can't seem to find it either.  To put things in perspective, I once held one of the 30mm AP rounds they use in the A-10 Thunderbolt's gatling cannon, and that sucker is BIG!  About the size of a man's forearm (not my pic, btw):

http://mybloggityblo...389largeon2.jpg
(Those two puny rounds next to it?  A .50 cal and a .556)

We're talking about rounds with 4-5 times the diameter, and since neither the 122 or 152mm guns were really designed with an AT role in mind, their propellant charges needed to be proportionally much larger to achieve a high enough muzzle velocity to reliably knock out armored vehicles.  Four feet+ is not an overestimation by any means.

[Killertomato]

The KV's 152mm shells weigh almost 90 pounds, and since it's two-piece, you'd have to load the powder charge in separately. Combine that with the miniscule amount of space in a KV-2's fridge turret, and it's easy to see why loading shells takes so long.

[_Freddy_]

Compare the rounds in this image, notice the two 88mm rounds, one for the Tiger I and one for the Tiger II.
The two German 50mm rounds, one for the 50mm L42 and the other for the 50mm L60.
The UK 6pdr (57mm) compared to the US 75mm from the Sherman.

http://www.quarry.ni...tankgervsuk.jpg

Quote

GERMAN & BRITISH WW2 TANK GUN AMMUNITION

37x249R (3,7 cm Pak / Kwk AP), 50x289R (5 cm L/42 Kwk Pzgr 40), 50x420R (5cm L/60 Pak 38, Kwk), 75x243R (7,5 cm L/24), 75x495R (7,5 cm L/43 and L/48: later Pz IV), 75x640R (7,5cm Kwk 42 L/70: Panther tank), 88x571R (8,8 cm L/56: Tiger 1), 88x822R (8,8cm L/71: Tiger 2).

47x376R (3 pdr Hotchkiss, similar to but slightly longer than 47x351R interwar tank), 40x304R (2 pdr AP), 57x441 (6 pdr APDS), 75x350R (US/British 75mm HE), 76x583R (17 pdr APDS), 76x420R (77mm mm in Comet tank), 76x134R (3" Howitzer for close-support tanks), 95x206R (95mm Howitzer for close-support tanks).

[Gohibniu]

Also some guns would require complicated procedures before refiring. For example, the Char B had a compressed...air blowdown to expel propellant gases between shots on its howitzer.

[TheHighRoller]

the KV 152mm was just a Howitzer, that just needed the shell to be loaded into the gun. It could fire fast, but it was risky cuz it could break something if it shot too much fast, or it wouldnt have accuracy. Plus KV couldnt carry much shells of those, and the crew's were not complete, most of them were just a commander a gunner a loader and sometimes a driver.

[_Freddy_]

TheHighRoller, on Apr 08 2012 - 20:36, said:

the KV 152mm was just a Howitzer, that just needed the shell to be loaded into the gun. It could fire fast, but it was risky cuz it could break something if it shot too much fast, or it wouldnt have accuracy. Plus KV couldnt carry much shells of those, and the crew's were not complete, most of them were just a commander a gunner a loader and sometimes a driver.

The round for the KV 2's 152mm gun used separate ammunition (projectile and propellant), the projectile weighed 40kg alone so manhandling that was a task even without the restrictions of the turret.

You can see the size of the projectile in this picture
  

[sirdano]

Something else everyone forgets is the tube is going to get hotter the faster you fire. So you can not quick fire or you will damage the barrel or cook a round off in the tube.

[CommissarRykov]

KV-2s also suffered for the fact ammo was scarce as they were having to use HE shells from the Red Navy Battleships. As the war heightened it became near impossible to requisition shells from the Red Navy thus why the KV-2 was discontinued. Imagine lugging around shells in cramped quarters like that where in a navy vessel it would be fed through the ships magazine.

[_Freddy_]

CommissarRykov, on Apr 12 2012 - 16:47, said:

KV-2s also suffered for the fact ammo was scarce as they were having to use HE shells from the Red Navy Battleships. As the war heightened it became near impossible to requisition shells from the Red Navy thus why the KV-2 was discontinued. Imagine lugging around shells in cramped quarters like that where in a navy vessel it would be fed through the ships magazine.

The KV2 used a modified 152-mm howitzer M1938 (M-10) the M10T not a naval gun (howitzers fire a heavy shell in a high arc so have a fairly limited range).

The KV2 was discontinued (some were converted back to KV1) because it was designed for a specific purpose, breaking through fortified defences in Finland.

The KV2 had problems in that the KV was a slow a tank as it was, with the huge heavy turret on it it became slower and put more strain on the engine and transmission. The turret could not be rotated if the vehicle was not on almost level ground. With the huge turret it was a bigger target, harder to conceal and of limited use in a mobile battle.

I have never heard that they were getting their munitions from naval sources?, the Soviets did have supply problems of spares, fuel and munitions especially early on due to loss of transport and depots but that applied to all equipment.

[CommissarRykov]

_Freddy_, on Apr 12 2012 - 17:32, said:

The KV2 used a modified 152-mm howitzer M1938 (M-10) the M10T not a naval gun (howitzers fire a heavy shell in a high arc so have a fairly limited range).

The KV2 was discontinued (some were converted back to KV1) because it was designed for a specific purpose, breaking through fortified defences in Finland.

The KV2 had problems in that the KV was a slow a tank as it was, with the huge heavy turret on it it became slower and put more strain on the engine and transmission. The turret could not be rotated if the vehicle was not on almost level ground. With the huge turret it was a bigger target, harder to conceal and of limited use in a mobile battle.

I have never heard that they were getting their munitions from naval sources?, the Soviets did have supply problems of spares, fuel and munitions especially early on due to loss of transport and depots but that applied to all equipment.

Sorry I got that backwards the KV-2 was authorized to use 152mm AP but it was naval issue and thus unable to be used by the Red Army thus leading to sole use of artillery munitions.

KV-2

[RobSmith]

One thing to consider is that many of those guns needed to be in a specific position just so you could open the breach. So when you consider the time it takes to fire, lower the gun, open the breach, get rid of the old shell case, insert a new projectile, ram it, insert a new primed case and power charge, close the breach, elevate the gun, aim and fire again .... A minute or more is not so unrealistic.