Aircraft / Aviation Vehicles & Artillery Infantry Arms Warships & Submarines Military Pay Chart (2023) Military Ranks
Infantry Small Arms / The Warfighter

Type 10, 50mm Grenade Discharger

Light Mortar / Grenade Launcher [ 1921 ]

The lightweight Type 10 operated from a trigger action and suffered from limited range.

Authored By: Martin Foray | Last Edited: 02/17/2017 | Content ©www.MilitaryFactory.com | The following text is exclusive to this site.

The 50mm Type 10 was the first of two primary "light mortars" to serve with the Imperial Japanese Army during World War 2. Introduced as early as 1921, the Type 10 was hardly anything but a light mortar design when compared to its contemporaries. The weapon essentially fired what was nothing more than the highly-adaptable Type 91 hand grenade (fitted with stabilization fins) and thusly became regarded as a "grenade discharger" or grenade launcher than a true light mortar. To add to its inherent limitations, the Type 10 was severely restricted in terms of effective range - essentially ranged out to about 175 yards - making the system an extremely-local, fire-support weapon. The limitations of the Type 10 eventually spurred the development of a better solution, this inevitably becoming the heavier, rifled-barrel Type 89 - though also termed a "grenade discharger". The Type 10 was also fielded in the Second Sino-Japanese War between China and Japan.

The Type 10 design centered around a smooth-bore firing tube attached to a simple baseplate. The weapon was loaded from the muzzle like most any other mortar system and fired by way of a trigger-type mechanism. Range was controlled via an adjustable gas vent. As a smooth-bore weapon, the Type 10 relied on the fins on its projectiles to maintain a flight trajectory. The typical projectile round became the Type 91 High-Explosive (HE) grenade though smoke (Type 11) and illumination rounds (Type 10 Flare/Signal, Type 91 Pyrotechnic) were part of the Type 10's forte. Therefore, the greatest strengths of the Type 10 lay not only in its lightweight design but also in its ammunition variety. The operator need only to set the launcher down to the ground and angle the tube away from him in preparation to fire. A live projectile could then be dropped down the muzzle, the vent gas system adjusted for range and the trigger mechanism activated to complete the firing operation.

With the arrival of the Type 89 in 1929, the Type 10 was relegated to target illumination duty and the like. Nevertheless, the weapon remained in service from 1921 to 1945 alongside the Type 89 and saw heavy use in the Pacific Theater.

An American translation error erroneously referred to the Type 10 and Type 89 grenade launchers as "knee launchers". This came from the Japanese manual which instructed soldiers to carry the launcher with the baseplate clipped at the belt, leaving the firing tube dangling out over the thigh. For a time, American GIs mistook this to mean that the mortar could be fired from the thigh, leading to a few accidents via experimentation as the weapon still packed quite a recoil when fired despite its small size and light weight. Such firing almost assured the operator a broken leg.©MilitaryFactory.com
Note: The above text is EXCLUSIVE to the site www.MilitaryFactory.com. It is the product of many hours of research and work made possible with the help of contributors, veterans, insiders, and topic specialists. If you happen upon this text anywhere else on the internet or in print, please let us know at MilitaryFactory AT gmail DOT com so that we may take appropriate action against the offender / offending site and continue to protect this original work.


Service Year

Imperial Japan national flag graphic
Imperial Japan


Light Mortar / Grenade Launcher

National flag of modern Japan Imperial Japan
(OPERATORS list includes past, present, and future operators when applicable)
Fire Support
Capable of suppressing enemy elements at range through direct or in-direct fire.

Overall Length
525 mm
20.67 in
Barrel Length
240 mm
9.45 in
Empty Wgt
5.73 lb
2.60 kg



Muzzle Loading; Trigger-Actuated

(Material presented above is for historical and entertainment value and should not be construed as usable for hardware restoration, maintenance, or general operation - always consult official manufacturer sources for such information)



Sample Visuals**

Graphical image of an infantry mortar projectile / shell
Rounds / Feed

Cartridge relative size chart
*May not represent an exhuastive list; calibers are model-specific dependent, always consult official manufacturer sources.
**Graphics not to actual size; not all cartridges may be represented visually; graphics intended for general reference only.
Max Eff.Range
213 ft
(65 m | 71 yd)

Type 10 - Base Series Designation

Military lapel ribbon for the American Civil War
Military lapel ribbon for pioneering aircraft
Military lapel ribbon for the Cold War
Military lapel ribbon for the Korean War
Military lapel ribbon representing modern aircraft
Military lapel ribbon for the Ukranian-Russian War
Military lapel ribbon for the Vietnam War
Military lapel ribbon for the World War 1
Military lapel ribbon for the World War 2

Ribbon graphics not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns / operations.

Images Gallery

1 / 1
Image of the Type 10, 50mm Grenade Discharger
Views of the Type 10 50mm grenade discharger and its 50mm grenade


Disclaimer | Privacy Policy | Cookies

2023 Military Pay Chart Military Ranks DoD Dictionary Conversion Calculators Military Alphabet Code Military Map Symbols

The "Military Factory" name and MilitaryFactory.com logo are registered ® U.S. trademarks protected by all applicable domestic and international intellectual property laws. All written content, illustrations, and photography are unique to this website (unless where indicated) and not for reuse/reproduction in any form. Material presented throughout this website is for historical and entertainment value only and should not to be construed as usable for hardware restoration, maintenance, or general operation. We do not sell any of the items showcased on this site. Please direct all other inquiries to militaryfactory AT gmail.com.

Part of a network of sites that includes GlobalFirepower, a data-driven property used in ranking the top military powers of the world, WDMMA.org (World Directory of Modern Military Aircraft), WDMMW.org (World Directory of Modern Military Warships), SR71blackbird.org, detailing the history of the world's most iconic spyplane, and MilitaryRibbons.info, cataloguing military medals and ribbons.

View day-by-day actions of the American Civil War with CivilWarTimeline.net. View day-by-day actions of World War II with SecondWorldWarHistory.com.

©2023 www.MilitaryFactory.com • All Rights Reserved • Content ©2003-2023 (20yrs)