The Type 38 (75mm) Field Gun was a Japanese Field Artillery piece designed in the early 20th century. The original design, of German origin, was built by the Osaka Arsenal for the Japanese Artillery, serving as an infantry support gun in the field.
The Type 38 Field Gun was a direct copy of a German design manufactured by Krupp. This design was the fairly basic design of Field Guns at the time, including a basis hydrospring recoil system, solid box tail and gun shield, with seats for the crew. This basic design meant that larger numbers of the Type 38 could be constructed in a shorter space of time.
The Type 38 had a conventional interrupted screw breech block mechanism, which would later be used on the Type 41 Cavalry Gun. However, when the Type 38 was developed in the 1920's (to bring the design into line with other Field Artillery pieces) this breech system was changed for a horizontal sliding wedge design, intended to speed up the loading process. The entire gun, including the barrel, carriage and breech mechanism, weighed around 2,090lb and was made entirely in steel.
The Type 38 was mounted on a wheeled gun carriage, with a solid box trail fitted, giving an overall elevation adjustment of between -8˚ (to the horizontal) to +16˚. The "Improved" Type 38 saw the carriage modified to give a significantly greater change in elevation, from -8˚ to +43˚, giving the possibility for the Type 38 to be used in an anti-aircraft role should the need have arised.
The Type 38 Field Gun fired a 2.95in (75mm) diameter 13.3lb (6.0kg) shell. The type of shell that the Type 38 would fire included firing High-explosive shells, shrapnel, armour-piercing warhead as well as gas shells and tactical shells (ie smoke and illumination shells).
There is little recorded use of the Type 38 Field Gun before the Second World War, by which time the Type 38 was considered obsolete. Nonetheless several examples were used in the Pacific Theatre of the Second World War, although, like its Horse Artillery counterpart the Type 41 Cavalry Gun, the Type 38's actual use in combat is unknown.
That being said the Type 38 was shown to have been used during the Second Sino-Japanese War (1937 - 45) as well as in the series of boarder conflicts with the Soviet Union throughout the 1930's and 1940's. Yet the Type 38 was still considered obsolete even in these relatively early (compared to the beginning of fighting in the Pacific Theatre of World War Two) engagements, having been largely superceeded by the Type 90 Field Gun.
The designation, "Type 38", comes from the fact that the Type 38 Field Gun was adopted by the Japanese Military in the 38th year of Emporer Miji's reign, as it was common practice to name a military arm with the year it was adopted in the Emperor's reign in Japan.