305 mm Hungarian ammunitions

[guardianangel]

The 305 mm Hungarian ammunitions are very rare because there wasn't produced so lot and mostly was used in the Sovierunion. Nowadays in Hungary I don't know piece which was produced in between the two world war period. In the museums and collections I only find the Austro-Hungarian pieces. For a long time I believed these mortars from the WW I also used ammunitions from the WW I or buyed from someone else and Hungary never produced in this time (1935-1945). But the last two years I find a case in a collection from 1938 and a shell fragment which came from this time.

Historic background:
After the end of the WW I the Trianon peace-treaty also seriously plagued the new founded (in 1922) Hungarian Rolyal Army. The artillery was hardly limited; the heavy artillery was prohibited. In spite of this in the country area remained many artillery pieces which was disagreed from the treaty. Betwen them was 5 piece 305 mm M1911 and M 1911/16 mortar. They were used in the Austro-Hungarian Monarchy joint-army but after the collapse its remained in Hungary. The audits which was by the Antant these mortars survived in disattached and hidden condition. After the 1930 period this 5 mortar was the base of the heavy artillery. Unfortunatelly the deterioration in its condition was as serious, that in 1932 the Hungarian Office of Technology stated: 4 piece from the 5 need change the inside barrel due to the abrasion. The heavy artillery became more and more inportant as the area-revision of the lost parts of Hungary placed bigger and bigger, in the political mentality from time to time. In 1939 all of the mortars was modernized, and decided to fit them with ammunitions. In accordance with this the biggest ammunition factory in Hungary the Weiss Manfred Ltd. produced 4179 piece demolition shell in Csepel. These shells were the 300 kg M34. In 1938 get up the new artillery units the 101 (placed at Székesfehérvár), 102 (placed at Hajmáskér) and 103 (placed at Hajmáskér) battery in the Army with these mortars and 3-3 21 cm M1940 howitzers. At the end of 1943 all of these mortars were losted. Only one came back in usable condition from the River-Don, Szovietunion. Another one was seriously demolised.

[guardianangel]

This page from a manual from 1939. It is show the three types of the shells:

M11/33
Weight:385 kg
Maximal muzzle velocity: 329 m/s at 12,46 kg powder charge
Maximal shooting range: 9300 m

M15/33
Weight: 287 kg
Maximal muzzle velocity: 409 m/s at 14,49 kg powder charge
Maximal shooting range: 12500 m

M34
Weight: 300 kg
Maximal muzzle velocity: 367 m/s at 12,46 kg powder charge
Maximal shooting range: 12500 m

They was painted with normal olive green and a band in the centre of gravity. If this band was
blue = carbon steel without hardening;
white = hardened carbon steel;
red = alloy steel

If they wasn't fit delay powder the sure-lethal fragmentation radius was: 25 m (385 kg) or 20 m (300 kg); the effective radius was: 75 m (385 kg) or 60 m (300 kg); dangerous radius: 1000 m

if they was fit with delay powder, they can penetrate 2,5 m reinforced concrete. In normal soil it can explode-out 3-6 m diameter and 1-4 m deep hole.

[guardianangel]

Here is a fragment from a shell. You can see the weight: 386 kg it is a little bit difference from the manual. Maybe a new type(?). It was fitted with delay powder: K-vel. I can recognise the date by the driving band chanel. The knurling in the Austro-Hungarian shell is long lines paralell with the shell base. This fragment is knurled by small pyramids. It is the footprint the normal 1930-1943 Hungarian knurling technology. This shell was double plated. The second plate was only covered the main base with the fuze. The driving bands were different thickness. The lower was the thicker.

[guardianangel]

Fuze was 33M or 34M base fuze. Both of them is the same mechanism the difference is the complicated or simple design. Both of them is graze hitting mechanism with detonator safety device (work by centrifugal force). Possible the delay powder but it should fit in the factory. It couldn’t set at the units. If it was fitted with this on the shell was stemped: K-vel. Other case: K-nélk.

[guardianangel]

You can see the big brass ring wich move down when the shell is fired. Pressed the spring and join the inside ring which held the balls in position. When the acceleration is ended the spring move foreward the brass ring with the ball-holder ring. Balls go away by the centrifugal force. On impact the primer holder brass weight run foreward. Pressed the safety spring and hit the primer to the pin. The fire go to the delay powder (if it is placed) and after reach the safety element wich armed by the centrifugal force. Then explode the booster. The house of the booster is as big and strong that the effect is like a deffensive handgrenade.

The 33M fuze has aluminium body ad it is schrewed in a bigger detonator house. More complicated than M34 but the same mechanism and safety device.

[guardianangel]

Here is the case compared with a Russian 76,2 mm cored ammunition.

[guardianangel]

Manufacturer code: Á and H is one sign. Means: Állami Hadianyaggyár it was the other name of the ammunition giant Weiss manfred Ltd.
The ctown is the acceptance with No1.

[guardianangel]

Manuacturing year: 1938
Lot number: 1 (in this calibre one lot was 250 piece)
Name of the gun: 10 cm 14D 16M The 10 cm 14D means the 305 mm mortar. It is interesting, because in the hidding-time all guns which was bigger calibre than 100 mm was code name and all code started with 10 cm. Dhe difference between them was the letter a, b, c, d. Why used code in this case? Everybody see it is not 10 cm. In a 10,5 cm case this code is acceptable but in 15 and 305 mm? In a 15 cm ammunition manual from 1938 we can see ammunition drawings with 149,8 mm diameter. But the text say: ammunitions for 10 cm 14b M guns. Strange...

[guardianangel]

Here is a page from a manual. Showed the case, the charges, the transporting box and the shell transporting frame.
:lol:

[PzGr40]

Hi Guardianangel, that's a great article abaout a shell I've never heard of. Very interesting! My printer is allready busy printing it all out for my archives. The cutaway of the fuze is absolutely perfect; did you make it yourself? Thanks a lot , with regards Pzgr40 :D

[guardianangel]

Hi PzGr40!

The cutaway is not mine and I get this pictures from somebody else who get it from the cutaway maker. The picture original name was 100 mm_hu 1 and 2 so that person know where it came from but don't know the type name. Nice piseces and I would like one also! :D

[mauser]

The caliber is a little to big for me, but I am impressed. A wonderful article. :P

Thank you

Mauser

[guardianangel]

Here is this year most important found for me. It was found by the Hungarian EOD unit during a former neutralization area clearing. It is at the border of Budapest; there will start the construction of the new North River-Danube bridge.
This shell recognition is still in progress...

[guardianangel]

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[PzGr40]

very Nice. Is it a very rare find , or do you find them more often?
Do you have a cutaway drawing of this shell?
Are you going to blow it up?
Regards and thanks for the nice pictures, DJH

Ps. It seems to have two drivingbands instead of the one in your drawings on page one. Modified design?

[guardianangel]

@PzGr40: It is very rare actually this is the first piece between the word wars time. Drawing is just what I publicated here. Detailed drawing will made out from this shell. It is reserved because inside inert filling - my former colleauges sad -.