30mm aircraft automatic gun.

[Panzerknacker]

A rarity, close up pictures of the Ho-155 30 mm guns emplaced in a Nakajima Ki-84 Army fighter.

http://img81.imageshack.us/img81/5264/ho155wh7.jpg


http://img81.imageshack.us/img81/5176/ho1552oh8.jpg

[Tony Williams]

That looks like a pretty effective muzzle brake!

[Panzerknacker]

It does, a little more information about this design.

Had WW II continued into 1946, the IJA 30 mm Ho-155 Browning machine cannon (often mis-designated Ho-105) would have become first line anti-bomber armament in IJA fighters and interceptors. It was starting to be used in early 1945, if only on a trial basis, and gun production was well under way. The four images attached, though of varying quality, show the evolution of this gun. They are approximately to scale, and are aligned to one another on the belt feedway.
http://www.j-aircraft.com/research/Evolution.jpg

[genkideskan]

Here are two cartridges for the Ho 155.
Left a TP and an HE at right.

[Panzerknacker]

Nice "salatgurkes" :shock:

The case was 30x...117 mm ??, not sure.

[genkideskan]

Yes it is a 30 x 115 .... but I have heard of 116mm cases, too.

Any idea of gun system -- looks like an browning system.

[tom!]

Hi.

The designation "Ho" indicates that it was a Hochkiss system machine cannon....

Yours

tom! ;)

[Panzerknacker]

According to this was a Browning type so I suppose is operated by short recoil.

http://www.j-aircraft.com/research/30_mm_ho155_browning.htm


The designation "Ho" indicates that it was a Hochkiss system machine cannon....



That is funny I tough it was a japanese word.

[genkideskan]

"HO" is a japanese character and used to ID aircraft guns and ammo. Nothing to do with Hotchkiss. Very similar to the "KI" character used to ID army aircrafts.
These Ho 155 gun is more a Browning copy I guess.

[Major Walter Schmidt]

Ho is ホ in japanese.

[tom!]

Hi.

sometimes it´s necessary to think and look before writing.

"Ho" stands of course not for Hotchkiss but for gun. :oops:

I stumbled on the following article on the Ho 155::

http://www.j-aircraft.com (http://www.j-aircraft.com/research/30_mm_ho155_browning.htm)

Yours

tom! ;)

[Tony Williams]

30x114 is the cartridge designation I'm used to.

There were (at least) two different models of the Ho-155: the Ho-155-I had the squared-off receiver shape, weighed 50 kg and fired at 400 rpm. The Ho-155-II had the more sloping shape, weighed 44 kg and fired at 500 rpm.

[genkideskan]

The army used a 37mm gun too. The Ho 204. It was used f.e. in the Ki 46 III Dinah. I still look to find more fotos.
The gun weights about 130 Kg, muzzle velocity 710m/sec and a rate of fire 400 rds/min. The design was started as an anti tank gun.
The cartridge was a 37 x 145.

[Tony Williams]

The army used a 37mm gun too. The Ho 204. It was used f.e. in the Ki 46 III Dinah. I still look to find more fotos.
The gun weights about 130 Kg, muzzle velocity 710m/sec and a rate of fire 400 rds/min. The design was started as an anti tank gun.
The cartridge was a 37 x 145.

This is another scaled-up Browning.

I doubt that it was ever intended as an anti-tank gun: that may be the Ho-203, a 37mm gun which used the same ammo as an anti-tank gun.

[genkideskan]

Well, we all need documents for our threads. These japanese document is a crude translation and I will ask a japanese friend for a new better translation.
These document mentioned that the gun was developed as an anti tank gun -used in gondolas under the wings. Later it was used elsewhere of course.
The cartridge is a more or less complete new developement.
The Ho 203 used a 37 x 133 R cartridge originally made for a small trench gun.
The tank and anti tank round is a 37 x 166 R.

[Panzerknacker]

Beautiful information and pictures boys, interesting the "japanese Schräge musik", keep up the god job :) !! step by step we are uncovering this little known topic.

I find a little picture of the Ho-204 37 mm, "horsecollar" feed autocannon. it remember me the loading system in the Airacobra gun.


http://i28.tinypic.com/2aiikvk.gif

[Tony Williams]

Well, we all need documents for our threads. These japanese document is a crude translation and I will ask a japanese friend for a new better translation.
These document mentioned that the gun was developed as an anti tank gun -used in gondolas under the wings. Later it was used elsewhere of course.
The cartridge is a more or less complete new developement.
Oh, an airborne anti-tank gun - that's possible, I suppose, but I think it is unlikely because the performance of the cartridge was quite low, and armour penetration would have been limited.

The Ho 203 used a 37 x 133 R cartridge originally made for a small trench gun.
The tank and anti tank round is a 37 x 166 R.
Not quite - the 37x134R cartridge was actually developed for the Type 94 tank gun. The Type 94 anti-tank gun, and the Type 98 tank gun, both used the 37x165R cartridge. So did the Type 94 manually-loaded aircraft gun fitted to some Ki-45 planes (I used to think this used the 37x134R, but I was wrong).

Edit to add: the Ho-203 used yet another round, the low-velocity 37x112R.

[Tony Williams]

I find a little picture of the Ho-204 37 mm, "horsecollar" feed autocannon. it remember me the loading system in the Airacobra gun.

No, that's the Ho-203.

[Panzerknacker]

No, that's the Ho-203.

You are correct this jap guns topic is beginning to lost me. :rolleyes:

So many cartrigdes cases for the same caliber...

[genkideskan]

The list of japanese trial aircraft guns fills two pages :mrgreen:

[Panzerknacker]

Hehe, someone might think that the germans had a lot of them , seems the japs were not behind in expermiental bussines..

Some pictures of experimental Mgs and MKs from "The machine gun Volume 3" J.M Chinn.

http://img521.imageshack.us/img521/8225/87743148ui1.jpg


http://img520.imageshack.us/img520/4355/25319102yp0.jpg

[genkideskan]

The Ho 203 was with a length of 1,50m and a weight of 89 kg a very compact weapon.Tony is right it fires the 37 x 111 R cartridge.The cage is fixed to the gun and holds an 15 shot belt. Rate of fire was 120 rd/ min.
Ho 203 is written to the cartridge case and the projectile is shorter and lighter than the original load for the Type 11 (1922) army infantry gun.
It was used in the nose of the Kawasaki Nick fighter and trials where made in Dinah rec. planes in the night fighter role.

[genkideskan]

The Ho 401 was very similar to the Ho 203 gun. There are 17 cartridges in the cage. The gun weight was about 160 Kg, the length was app. 2m.

http://img167.imageshack.us/img167/1011/ho401gunrr2.jpg (http://imageshack.us)


http://img98.imageshack.us/img98/4066/ho40157mmgundg4.jpg (http://imageshack.us)


The gun was used in the Ki 102 Randy, mounted in the nose. Mounts in the bomb bays are known too.

Here a Ho 401 in a ventral position- note the pneumatic.
http://img177.imageshack.us/img177/4205/ho401bellylr3.jpg (http://imageshack.us)

The powerful gun in the nose section. Rate of fire 80 rd/ min.
http://img177.imageshack.us/img177/7627/ki102qf7.jpg (http://imageshack.us)


http://img98.imageshack.us/img98/4776/ho40157mmki102randyjf6.jpg (http://imageshack.us)

The 57 x 121 R ammunition was very similar to the cartridge used in the 57mm tank gun.
The projectile was shorter and use an smaller fuze made for 20mm ammo . It was fired at 560m/sec.

http://img169.imageshack.us/img169/6893/ho40157x121rti9.jpg (http://imageshack.us)

.

[Tony Williams]

Yep, the Ho-401 was just a scaled-up version of the Ho-203. It suffered from the same problems of a low rate of fire and a low muzzle velocity, which together made it difficult to hit targets unless you got very close.

[Panzerknacker]

Excellent again Lothar

do you know what was the heavy gun used by the Rikugun Ki-93 ??

http://ww2photo.mimerswell.com/air/jap/rikugu/04413.jpg

[genkideskan]

Two sets where planned. Anti ship role armed with a Type 88 75mm gun in a venstral bay, like
the Ki 109.

http://img76.imageshack.us/img76/4307/type8875mmfy8.jpg (http://imageshack.us)

Here is a 75 x 493 Type 88 HE shell with T 99 impact/time fuze. This shell was made for the AA gun. Nothing is known about the aircraft ammo. Probably a shorter shell with Type 88 impact fuze. See ammo pictured with the gun, that shell resembles the hollow charge shell.

http://img178.imageshack.us/img178/3171/type88ammofn5.jpg (http://imageshack.us)


Bomber defence role a Ho 401 in ventral position and 2 x Ho 5 20mm guns.

For rear defence a 12,7 mm gun.

[genkideskan]

The gun was manually loaded by the co pilot or the radio man. It was planned to carry 12 rounds, but when 22 planes where delivered to the unit 40 rounds where carried in bins installed in reach of the loader. The pilot aim an fire the gun.
A trained crew could fire 20 rd/min. The projectile reached 720m/sec.

[genkideskan]

I just have found 2 fotos of Ki 44 Tojo fighter armed with wing mounted
37mm Ho 203 guns. Normally the cage would need bulbed covers. May be the feed system was converted to magazine or belt feed.

http://i277.photobucket.com/albums/kk45/genkideskan/Japan/Ho%20203/37mmHo203.jpg

http://i277.photobucket.com/albums/kk45/genkideskan/Japan/Ho%20203/tojo437mm.jpg

[Tony Williams]

No, the Ki-44 never carried Ho-203 - that was a mis-identification. I have participated in long debates about this with Japanese aircraft gun researchers in the West and in Japan.

Japanese records indicate that the only gun bigger than the 12.7mm Ho-103 fitted to the Ki-44 was the 40mm Ho-301, which is what is shown in your pics. The reason that the barrels look different is that the bolt and front-mounted yoke have been drawn back because the bolt is cocked, so the front of the barrel is exposed (which it isn't in most photos of the gun).

There never was a different ammo feed for the Ho-203 and, as you say, the continuous-belt "squirrel cage" magazine was far too bulky for wing mounting.

[genkideskan]

Possible, but the guns on this fotos protrude a lot more than the 40mm Ho 301 in known fotos, at the wing front.
You are right the barrel diameter changes -depending on a cocked or uncocked Ho 301 gun, but not the length.

I wonder if they convert the Ho 203 to belt feed and use the 37 x 110 rimless round for that. So there is no bulk nessessary. That would declare the rimless round. The rim was anoying the push through in a what ever link.
The cage couldt be removed easily and the inside belt works without cage, mount the gun turned at 90°, ready.

May be we will look for more fotos and informations and hopefully something showes up.
What is a fact today might be totally different tomorrow.

[Panzerknacker]

Thanks for the info about the Ki-93.

In regard to the 37 mm gun...shouldnt be more logical to use a Ho-204 instead the 203 model in wings emplacements ?

Honestly I dont think the bulky Ho-203 even modified could fit there.

[genkideskan]

Logical ? .... in war ? :mrgreen:

yeah - needs more research, we will see.

[Panzerknacker]

Well....logic what is said logic there was none, kiene logic with the japanese specially in regard of cartrigdes cases and gun estandarization, so many models , so many calibres, so many designs, so many...errors.

[genkideskan]

Now it might be fact that the Ho 203 never was wing mounted in Ki 44.

The cage is part of the feed system and cant be removed without major modifications. So we can forget this theory :mrgreen:

Problem solved

The Ho 155 never was officially adopted, so at wars end it has still an experimental status.

[Panzerknacker]

So we can forget this theory


Step by step we are closer to the truth.