Ammunition, Guns and Mountings Definitions for Japan
about Naval Guns
of the World War II era
This document defines abbreviations, designations and terms for Japanese ammunition and guns.
Dan, Dangan or Hôdan - Shell or projectile.
Eiryôdan or Eikôdan - Tracer Shell.
Endan - Smoke shell.
Enshûdan - Exercise (inert training) projectile.
Jigen Enshûdan - Time Exercise (time fuzed) projectile.
Mokuhyôdan - Target Shell.
Seidan (before 1938) or Shômeidan A (after 1938) - Illumination (star) shell without parachute.
Shômeidan B - Illumination (star) shell with parachute.
Ryûsandan - Shrapnel shell.
Shôi ryûsandan (Sankaidan) - Incendiary shrapnel shell (Fragmentation).
Tekkôdan - Armor Piercing (AP) projectile.
Hibô Tekkôdan - Capped Armor Piercing (APC) projectile.
Tsûjôdan - Common projectile.
Hibô tsûjôdan - Capped Common projectile.
Shôi tsûjôdan - Incendiary-common.
Chakushokudan - "Pillar coloring shell." Shell containing a dye for coloring the splash.
Chakuhatsu Shinkan - Percussion fuze.
Dan shinkan - Shell fuze.
Dantei Shinkan - Base fuze.
Dantô Shinkan - Nose fuze.
Fukudô Shinkan - Double action fuze (instantaneous and timed).
Kikai jigen shinkan - Time fuze.
Sakuyaku - Bursting Charge (inside projectile).
Bakuyaku - Explosive.
Sôyaku - Propellant charge.
Jô sôyaku - Full charge.
Jaku sôyaku - Reduced charge.
Gen sôyaku - Light or half charge.
Kyô sôyaku - Heavy or proof charge.
Kayaku - Powder (gunpowder, propellant powder).
Bursters - The following description is adapted from "Japanese Cruisers of the Pacific War" by Eric Lacroix and Linton Wells II:
Shimose, a picric acid burster roughly equivalent to British Lyddite, was adopted prior to the Russo-Japanese War. Like most bursters derived from picric acid, the Japanese found that shells using this had a tendency towards premature detonation.
Following the end of World War I, the Japanese obtained a quantity of German AP shells which used a TNT - beeswax mixture for the burster (Fülpulver C/02) enclosed in a "pulp" mantle as a dampener and a wooden plug at the top of the explosive cavity which acted as a buffer against the impact shock. Based upon this knowledge, the Japanese developed a similar enclosure made of hardended stone plaster pulp and parafin and the burster was changed to a mixture of wax with Shimose. This development was in an advanced stage by 1922 when the Japanese purchased some AP shells from the British armament firm of Hadfields, Ltd., Sheffield, in order to examine the latest British improvements.
Lessons learned from this examination and from live-fire experiments were incorporated into the new shell designs finalized in June 1925 and adopted as the 5 Gô hibo tekkodan (APC Model 1925). These shells still had some degree of premature or low-order detonations and in 1928 they were replaced with the improved Type 88 (APC Model 1928) which had an improved container for the burster among other modifications. A few years later in 1931, the Japanese adopted TNA (tri-nitro-anisol), which was more stable explosive than shimose. This burster was designated as Type 91 bakuyaku (Model 1931 Explosive) and was used for the Type 91 APC and Type 1 APC shells during World War II.
Propellants - Cordite in various forms was used by the Japanese from about 1890 to the end of World War II. Different formulations were used, most containing about 30 percent nitroglycerin and 65 percent nitrocellulose with the remainder being stabilizers. Nominal diameters of the cords were given in units of 0.1 mm (0.004"). For example, DC80 would be cordite with cords of 8 mm (0.315") diameter.
Powder Bags - Powder bags appear to have been made from wool up to 1942 at which time silk ones were introduced.
Hô - Gun.
Kiju - Machine Gun.
Kôkei - Caliber (bore).
Kôsha-Hô - High Angle (AA) Gun.
Shiki - Type (year designation).
Sokusha-hô - Quick Firing Gun (QF).
Many European armament firms built guns for the Japanese Navy during the late 1800s and early 1900s. Some of the more famous ones are listed below.
Antotokuryû hô - Armstrong
HI hô - HI Type Gun (British Vickers), this is also shown as BI hô.
Kanot (?) hô - KA Type gun (French Canet).
Kuryôhaku hô - Koku Type Gun (German Krupp).
Ruizu kiju - RU MG (Lewis MG)
02 July 2008 - Benchmark
27 May 2012 - Updated to latest template
27 September 2015 - Corrected typographical error
30 April 2020 - Updated to HTML 5 format and reorganized datapage