Largest Guns on a WW2 Tank

Discussion on the tanks and other armoured fighting vehicles, which participated in World War 2.
smithd12
Recruit
Posts: 2
Joined: Mon Apr 09, 2012 7:32 am

Largest Guns on a WW2 Tank

Postby smithd12 » Mon Apr 09, 2012 7:57 am

Hi guys, just wondering if you can help me out!

I have for quite a while thought that the Largest Gun fitted to any Tank in WW2 was the 128CM gun fitted to the JagdTiger. Closely followed by the JS2 at a huge 122CM.

However watching a programme on the KV series of tanks I was reminded the the KV2 was armed with a huge, sorry......HUGE 152CM gun!

I have read quite a few publications that have stated the the gun on the JagdTiger was the biggest fitted to any tank. But this can't be the case, can it?

Am I getting something wrong here?

User avatar
Christian Ankerstjerne
Administrator
Administrator
Posts: 2506
Joined: Thu Jan 24, 2008 8:42 pm
Location: Denmark
Contact:

Re: Largest Guns on a WW2 Tank

Postby Christian Ankerstjerne » Mon Apr 09, 2012 1:23 pm

It depends on whether you define a tank strictly, or if you include other vehicles, too. The Jagdtiger was a tank destroyer, though the German Maus (armed with the same basic gun) was a proper tank (albeit one that never saw action). The Russian ISU-152 self-propelled gun was armed with a 152 mm howitzer, and was much more successful than the KV-2.

The largest-caliber self-propelled gun of World War II would be the German Karl-Gerät, with a 600 mm mortar, larger than even the heaviest railroad artillery piece. It certainly wasn't a combat vehicle, though, and would best be described as a mobile siege mortar. The 380 mm rocket launcher on the German Sturmtiger would be the largest-caliber weapon on an actual combat vehicle. The Japanese Ha-To, armed with a 300 mm mortar, is to my knowledge the largest-caliber conventional gun on a World War II vehicle. The largest artillery piece would be the 240 mm howitzer on the T92 HMC (though this vehicle never saw any action).

tom!
Rikugun Taii
Rikugun Taii
Posts: 215
Joined: Fri Feb 01, 2008 2:36 pm

Re: Largest Guns on a WW2 Tank

Postby tom! » Mon Apr 09, 2012 1:49 pm

Hi.

The Type 4 Self-Propelled Heavy Mortar Carrier Ha-To used an experimental muzzle loaded short-range siege mortar. The project was dropped in favour of the 20 cm and 40 cm rocket systems.

The largest japanese gun on an officially introduced AFV was the Type Meiji 38 15 cm howitzer from 1905 used on the Type 4 Gun Tank Ho-Ro.

The IJN Special Naval Landing Forces used 12 cm short howitzers introduced as close defence weapons for non-military transport vessels on some of their Type 97 Medium Tank Chi-Ha Kai as CS-tanks. The Shinhoto-turrets had to be modified and a short muzzle break was added.

Image

In Summer 1945 IJN tested the use of single mount Type 89 12,7 cm DP Guns instead of the turret on a Type 97 Medium Tank. I had a pic of such a vehicle on one of my crashed HD drives :x

Yours

tom! ;)

User avatar
Christian Ankerstjerne
Administrator
Administrator
Posts: 2506
Joined: Thu Jan 24, 2008 8:42 pm
Location: Denmark
Contact:

Re: Largest Guns on a WW2 Tank

Postby Christian Ankerstjerne » Wed Apr 11, 2012 2:36 pm

Do you have some information on the rocket systems that replaced the Ha-To?

tom!
Rikugun Taii
Rikugun Taii
Posts: 215
Joined: Fri Feb 01, 2008 2:36 pm

Re: Largest Guns on a WW2 Tank

Postby tom! » Thu Apr 12, 2012 11:44 am

Hi.

IJA differed between artillery guns, high-trajectory infantry guns (mortars) and mortars (short range heavy and siege mortars). Mortars were used by trench mortar units only. These were used to fire large warheads on short ranges. Weapons of these units were among others:
- Type 94 90 mm Mortar
- Type 2 120 mm Mortar
- Type 93 150 mm Mortar
- Type 96 150 mm Mortar
- Type 98 32 cm Spigot Mortar
- Type 4 20 cm Rocket Launcher
- Type 4 40 cm Rocket Launcher

Type 4 20 cm Rocket Launcher:

Image

The development ot the Type 4 20 cm rocket system started in Juli 1943 at 7th Army Research Institute as support weapon for amphibious landings. It should be fired from transport vessels, landing craft and supporting military vessels but also from terrain unsuitable for artillery and infantry weapons. The design included a mortar-like launching barrel including a bipod for shipbourne and land use and additionaly simple wooden rails for land use only. Innital tests were made at Osaka Army Arsenal in January 1944. The launcher could be assembled in 1 min 40 sec. It had 2 vents in the rear minimising the recoil. Behind the vents and below the muzzle firesafe mats had to be layed on board. The projectile was inserted in the launching barrel by a gas-tight hatch on the rear part of the barrel.
On land the projectile could be fired from wooden rails or even from the ground.

Image

The projectile had a diameter of 203mm. It was stabilised by spin generated by a special module below the propellant chamber. This module had 7 slightly spiralised holes generating the spin. The propellant consisted of three charges of Type 1 solid fuel (no idea what this is). The weight of the single propellant charges could be 8,2 kg, 8,9 kg or 9,6 kg depending on the needed basic range. The burning time was 2 seconds which lead to a maximum speed of 175 m//sec. The firing range was also effected by the angle of fire. The projectile could reach between 1400 m with smallest propellant charge and 65° angle of fire and 2400 m with maximum propellant charge and 45° angle of fire. A safety distance for the crew of 5 m around the launcher was necessary. The warhead consisted of a 16,5 kg Shimose charge and a standard Type 100 Mark 2 artillery impact fuze. The impact crater on sand had a depth of 1,5 m and a diameter of 6 m. Maximum weight of the projectile was 83,7 kg.

Image Image
The right picture was modified to show where the projectile is but it was made much too large.

The final tests were finished in February 1944 at Army Artillery school and the weapon system was officially introduced as Type 4 Rocket Mortar but the army officials disliked this designation as it was found unsuitable for such a different weapon. So it was changed to "Rocket Launcher" in May 1944. It was a cheap and easy to produce weapon. Total production numbers are unknown but a total of 70 Type 4 20 cm launchers were used on Iwo Jima and Okinawa. On both islands the launchers suffered from a lack of ammunition but the psycological effects of the quite loud rockets were nevertheless quite large. Several dozend launchers and most of the produced ammunition were stockpiled on the home islands for the expected invasion.

The projectiles were also used by IJN units with their 20 cm rocket guns. These guns were developed for short-ranged self defence (up to 2500m) but the avaliable datas on these weapons are very rare as most documents on these were destroyed before surrender. At least one of these guns was captured on Okinawa. In the rare western literature and on the net both weapon systems are very often mixed together but they were different developments.

Image
same gun with lafette for land use as captured on Okinawa

Data:
standard launcher:
Caliber : 203 mm
Barrel Length : 1.92 m
EL Angle of Fire : +40 to +65 Degrees
AZ Angle of Fire : 300 Degrees
Weight : 227.6 Kg

Projectile:
length: 1,019 m
Weight : 83.7 Kg
propellant weight 3 X 8,2 kg or 8,9 kg or 9,6 kg
maximum Speed : 175 m/sec
charge weight: 16,5 kg
maximum range : 2,400 m

Sources:
http://ja.wikipedia.org/wiki/%E5%9B%9B%E5%BC%8F%E4%BA%8C%E3%80%87%E7%B3%8E%E5%99%B4%E9%80%B2%E7%A0%B2
http://www3.plala.or.jp/takihome/

edit: removed 1 pic due to new informations

Yours

tom! ;)
Last edited by tom! on Thu Apr 19, 2012 10:03 am, edited 6 times in total.

User avatar
Christian Ankerstjerne
Administrator
Administrator
Posts: 2506
Joined: Thu Jan 24, 2008 8:42 pm
Location: Denmark
Contact:

Re: Largest Guns on a WW2 Tank

Postby Christian Ankerstjerne » Thu Apr 12, 2012 12:42 pm

As always, your posts are a pleasure to read, Tom.

Seems to me that the rockets were more sophisticated than the launchers.

tom!
Rikugun Taii
Rikugun Taii
Posts: 215
Joined: Fri Feb 01, 2008 2:36 pm

Re: Largest Guns on a WW2 Tank

Postby tom! » Thu Apr 12, 2012 1:49 pm

Hi.

Well, that´s the main points why these weapons were developed: simplification and raw material preservation. The easier and cheaper a weapon can be produced and handled the better for a county which is about to loose a war.

IJA even developed plans for extremely simple weapons made by local agricultural communities without many ressources or craftsmen. These included handgrenades made of pipes and concrete, bamboo spears, bamboo grenade dischargers using bamboo grenades, bamboo Panzerfaust and slow match fused blackpower rifles.

Yours

tom! ;)

User avatar
Christian Ankerstjerne
Administrator
Administrator
Posts: 2506
Joined: Thu Jan 24, 2008 8:42 pm
Location: Denmark
Contact:

Re: Largest Guns on a WW2 Tank

Postby Christian Ankerstjerne » Thu Apr 12, 2012 2:51 pm

Seems like the Germans took quite the opposite approach. Then again, I guess that's the difference between a country traditionally run by isolationanist buddhists, and a country traditionally run by authoritarian technocrats.

tom!
Rikugun Taii
Rikugun Taii
Posts: 215
Joined: Fri Feb 01, 2008 2:36 pm

Re: Largest Guns on a WW2 Tank

Postby tom! » Fri Apr 13, 2012 4:00 pm

Hi.

Type 4 40 cm Rocket Launcher:

Image

The development of a heavy rocket mortar was started in 1942 to replace the Type 98 32 cm Spigot Mortar. Goal was to get a weapon with a similar warhead, increased accuracy and shorter assemby/dissassembly time. In the early design phase a steel launcher tube was used. The ammunition was loaded by a small steel crane. The propellant module was inserted at the lower end of the tube through a hatch with the thruster nozzle below the tube. Then the explosive charge module was added to the top.

Image
first design using a steel tube and rocket with a standard 75 mm HE grenade placed in front for comparison

The first test results were quite good but the use of steel for the launcher was criticised. So a new launcher was designed. It consisted of an strengthened triangular frame with two hardened wooden rails screwed on parallel in the center. A wooden monopod was added to adjust the launcher to the necessary starting angle of 45°. On the lower edges sandbags were placed for stabilisation. Early tests showed some instabilities and so additional horizontal laths were added to the framework. For assembly of the 200 kg launcher and loading of the 507 kg rocket a simple guyed wooden bipod crane was avaliable.

The rocket consisted of a spin module, a propellant module and a warhead. The spin module had a hole with variable diameter (20 mm - 60 mm) in the center. A nozzle focusing the blast was placed below the hole. 6 44 mm holes angled to 25° were placed around the central hole to create a right-hand spin for stabilisation. The propellant module housed 37 propellant sticks made of 73 % smokeless powder and 27 % Nitroglycerin. Each had a length of 650 mm, a diameter of 47 mm and a weight of 1,78 kg = 66 kg total. The propellant was ignited by a Type 96 Electric Fuze using 300 mA DC or a Type 96 Friction Fuze. The warhead housed 98,28 kg explosives which was the same weight as in a 250 kg bomb. It was detonated by a Type 100 Mark 2 Fuze which fired on impact or timed.

The firing range depended only on the adjusted diameter of the central hole of the spin module. Minimum range was 2000 m with a 20 mm diameter, maximum range was 4000 m with 60 mm diameter.

The final tests were made in mid 1943 and serial production started in late summer 1943. In late 1943 several Rocket Battalions were formed and equipped with the first serial production launchers. These Battalions were under direct command of Area Armies and were used on Luzon, Iwo Jima, Okinawa and in China. At this time the battalions used both 20 cm and 40 cm launchers with 12 launchers and 84 rockets per battery, 3 batteries per battalion. Standard tactic was salvo fire by the whole battalion to minimise the thread of being detected and destoyed by counterbattery fire. Additional ammunition was carrried by the ammunition train. On Luzon 3rd Rocket Battalion had a total of 1000 rockets avaliable which were all fired. An unknown number of launchers and rockets were stockpiled in Japan for the expected invasion.

The Type 4 40 cm Rocket Launcher is often mixed up with the different IJN Experimental 45 cm Rocket Launcher:
Image

Data:
standard launcher:
Caliber : 400 mm
Length : 3,268 m
width: 2,720 m
EL Angle of Fire : 45 Degrees
AZ Angle of Fire : limited
Weight : 200,00 Kg

Projectile:
length: 1,8735 m
Weight : 507,6 Kg
propellant weight 37 X 1,78 kg = 66 kg total
maximum Speed : 220 m/sec
minimum speed: 155 m/sec
charge weight: 98,28 kg
maximum range : 4000 m

Sources:
http://ja.wikipedia.org/wiki/%E5%9B%9B%E5%BC%8F%E5%9B%9B%E5%8D%81%E7%B3%8E%E5%99%B4%E9%80%B2%E7%A0%B2
http://www3.plala.or.jp/takihome/
Ground Power Special Issue January 2005 "Less Known Army Ordnance Of The Rising Sun Part 1", Galileo Publishing Co. Ltd, Tokyo

Yours

tom! ;)

The Toastinator
Technican 5th Class
Technican 5th Class
Posts: 79
Joined: Sat Dec 10, 2011 4:18 pm

Re: Largest Guns on a WW2 Tank

Postby The Toastinator » Thu May 10, 2012 9:29 am

smithd12 wrote:However watching a programme on the KV series of tanks I was reminded the the KV2 was armed with a huge, sorry......HUGE 152CM gun!


This would be incorrect. It was 152mm, not cm. Even the biggest Battleships didn't mount cannon bigger than about 1/3rd that size.

User avatar
Hivner
Recruit
Posts: 1
Joined: Wed May 06, 2015 5:48 am
Location: 16 street
Contact:

Re: Largest Guns on a WW2 Tank

Postby Hivner » Mon May 11, 2015 6:28 am

Err..Gustav Gun; " its huge shells, each weighing 15 pounds (7.1 kg), was enough to destroy an ammunitions dump protected by 100 feet (30 m) of rock." I think you'll find the shells weighed more than 15,000 pounds.

Ricky
Quartermaster
Quartermaster
Posts: 8458
Joined: Sun Jan 27, 2008 3:42 pm
Location: Luton, UK

Re: Largest Guns on a WW2 Tank

Postby Ricky » Mon May 11, 2015 7:28 am

It might be the largest gun, but it certainly wasn't mounted on a tank!

Considering that specally adapted Pz IV tanks could only carry 4 shells for the Karl-Gerät... ;)
"Study the past, if you would divine the future"
-Confucius

"I am pedantic, I'm just being overshadowed by Ricky so it isn't as noticable as it would else have been"
-Skua

User avatar
jeaguer
Second Lieutenant
Second Lieutenant
Posts: 343
Joined: Sat Feb 02, 2008 11:32 pm
Location: Sydney

Re: Largest Guns on a WW2 Tank

Postby jeaguer » Wed May 13, 2015 12:37 am

.
no mention of the Brummbar , Sturmpanzer 43 using the much abused PZKW IV chassis and mounting a short barrelled 150mm

or the Hummel , with the same chassis and a real 150mm howitzer
admittedly one was an assault gun and the other a self propelled artillery
the biggest tank gun (breech loaded , turret fitted ) must have been the 122mm of the IS-2

Roel
Former Administrator
Former Administrator
Posts: 165
Joined: Tue Jan 29, 2008 3:07 pm
Location: London, UK

Re: Largest Guns on a WW2 Tank

Postby Roel » Sun May 17, 2015 11:34 pm

What was the calibre of the spigot mortar on the Churchill AVRE? Since it still had a rotating turret, that one might win the prize...
"The Athenians were born neither to have peace, nor to let others have it"
- Thucydides

Hoosier
Major General
Major General
Posts: 1042
Joined: Wed Jan 30, 2008 1:21 pm

Re: Largest Guns on a WW2 Tank

Postby Hoosier » Mon May 18, 2015 2:28 am

Petard 290mm spigot mortar.


Return to “Tanks in World War 2”



Who is online

Users browsing this forum: No registered users and 1 guest