Japanese 7.7 Semi-rimmed cartridges

I have some 7.7 semi rimmed cartridges that I need help identifying. I have been through Ken Elks book and still cannot determine what type of cartridges they are.

  1. Cartridge does not have any color marking around the neck. Primer does have a circle primer seat with a green enameled seal around the primer. Is semi-rimmed and weighs 26 grams. The bullet is pointed not flat and is copper without a steel core.
  2. Cartridge does have a red enamel around the neck. Primer has a circle seal with no color. Is semi-rimmed and weights 26.2 grams. The bullet is pointed not flat and is copper without a steel core.
  3. Cartridge does have a black enamel around the neck.Primer has a circle seal with no color. Is semi-rimmed and weights 23.4 grams. The bullet is pointed and not flat and has a steel core (checked with a magnet).

I would like to know what Type of cartridges these are and what weapons they were fired from.
Dwight Brown


Pictures would help to confirm what have.

Also you can take a look at this web sight which has good pictures and descriptions (use an online translator if need be): http://www.munizioni.eu/munizioni/index.php?option=com_content&view=article&id=213:7-7-x-58-sr-tipo-92-giapponese&catid=14:giapponesi


A very good web site. That is the first time anyone has directed me to the site. I found every thing I needed on the first two cartridges.
I could not find any information on the third cartridge.

I am only allowed one image upload. If you would want more I would have to send it to your email. Remember the bullet is Steel and semi-rimmed. I need to know what type it is and what weapon it was fired from.
Dwight Brown

Type 92 Armour Piercing as used in the Type 92 heavy machinegun. I think you’ll find the bullet jacket is actually brass but the core is steel - hence the magnetic attraction.


You are correct, it is brass with a steel core. I should have stated that.

I also found this information.

In 1932 Type 92 ammunition was developed for the Japanese Army’s new land service machine-gun, using the same semi-rimmed case as the Type 98. This allowed the ammunition to be used in the Type 89, Flexible/ fixed Machine-guns and the Type 92 heavy Machine-gun. This allowed a range of special Loads for both the Type 89 and the Type 92 to be used. These different loads required special markings, adopting a system of colored lacquer case mouth seals. These Armor Piercing cartridges consisted of a steel-cored brass bullet without a lead sleeve around the core. The designation for the ammunition was Type 92 AP for either the Type 89 AMG or the Type 92 HMG. This ammunition was also used later for the Type 92 Light Machine-gun.

Do you believe this to be correct??? I am not sure if the Light machine Gun was a Type 92 or Type 11…


The two type 89 guns (Vickers fixed, and Nambu flexible) and the type 92 Hotchkiss HMG fired the semi-rimmed cartridge. These were all army weapons and were, I believe, the only guns adapted to that cartridge. The type 11 was an army Nambu light machine gun in 6.5 m/m, and the navy type 92 was a version of the Lewis, adapted to the 7.7 m/m rimmed cartridge (that is, the .303 British).

Brian, Great web site. Thanks!!!

Just to confuse things Japanese further, the Army Air Force had a Vickers Aircraft Model (T89)Fixed in 7,7 T89 (Initially) and then could use the T92 Semi Rim Ammo, Whilkst the Navy had the Same Gun, but in T87/92 Rimmed (aka .303 British)

Japan’s Army/Airforce and Navy developed their MGs separately during the 1920s, based on Experiences of their Observers in the Western Front ( Theyt were impressed on the Potency and reliability of Vickers, Lewis, etc and the relevant .303 calibre Ammo, and so ordered guns of these types and millions of rounds of .303 ammo in the early 1920s to develop their own Guns and ammo.
Hence the Navy picked the Lewis and Vickers for their Small ships and Aircraft, whilst the Army stu7ck with the Nambu designs (T89 Flex, and Type 92 Ground) but still copied the Vickers as a Fixed gun in aircraft ( “Cowl” gun, accessible by Pilot for charging, same as in Navy aircraft…)
The situation was further complicated when the Army developed (on the Basis of the ZB26 & 30, captured from China) the T97 7,7 Tank MG ( again, T92 semi Rimmed, just two years before adopting the T99 Rimless ammo for Rifles, LMGs, and later ( 1940-41) a version of the T92 Medium gun, also in 7,7 T99 Rimless.( Not many made)
It was also found that the T99 rimless ammo could, in emergency, function quite well in T92/89 Semi-rimmed guns
but with lessened Ballistic efficiency, due to different Charges and Bullet weights. (Extraction OK due to the Large, strong extractor of the Nambu designed guns.)

So despite the confusion of similar “Calibre” Guns but different cartridges, the Japanese, did “Muddle Through” quite well ( and they even had the T98 Flex aircraft gun (German Design) IN 7,9mm…!!!

Doc AV

I took most of this info (below link) from Ken Elks book and a few other books a few years ago…
If anyone see’s any error, let me know.

Ammo one, just one typo…you mention 6.5x58(sic) instead of 6.5x50 (T38) in the initial chapter…
Otherwise all very corect at our present level of knowledge


The correct metric ID for the 6.5 m/m Arisaka catridge is 6.5x50SR, SR representing ‘semirimmed’. The jacket of the 7.7x58SR tracer round isn’t nickel plated but is rather a homogeneous layer of cupronickel. Jack