37 mm japanese land service
Two explosive projectiles are known, the oldest being the 13 Year Type which is readily identified by its large nose fuze. Although replaced by the later and much more common Type 94 explosive this projectile is known both in the 11 Year Infantry and Type 94 Tank gun cases. The Type 94 explosive uses the standard Type 93 fuze found on 20mm ammunition. A practice version of this projectile uses black powder instead of the picric acid/TNT filling on the full load.
All the other projectiles are armour‑piercing, mostly with base fuzed explosive fillings, which begin with a 12 Year Type AP/HE. The full load for this has a TNT filling and uses the Type 12 base fuze. A practice version substitutes black powder for this explosive.
This was followed by a Type 94 AP/HE which had a picric acid filling and Type 94 base fuze, which is probably the commonest of all the AP projectiles. A practice version of this has the HE cavity filled with sand and closed by a metal plug instead of the fuze An alternative training load used, as far as is known, only in the Type 94 tank gun, was the Type 96 armour‑piercing projectile. This was apparently a Type 12 with the long internal cavity filled with sand and metal base plug.
Finally, there is the Type 1 AP/HE projectile base on a similar German design which is noticeably shorter and more rounded in the olgive than the others. This has a filling of R.D.X. and paraffin wax and utilises the Type 1 base fuze.
In addition to the above, blanks are known for the 11 Year Infantry and Type 94 Tank guns. No details are forthcoming on these but they may have had no projectile and just a card and wad seal.
The HE round is provided with a small, short‑delay nose fuze. The radius of burst of the high­-explosive shell is not large and, consequently, not considered dangerous except at the point of impact or in a small enclosure directly penetrated.
The armour‑piercing projectile can pene­trate 1.32 inches of armour plate in a direct hit at 1,000 Yards, or 0.96 inch if the shot hits at a 30 degree angle. A base fuze is used with the armour-­piercing projectile.
Length:
Total 9 inches
Projectile 43/4 inches
Shell 51/4 inches
Diameter:
Projectile 17/16 inches (37mm)
Shell base 1 13/16 inches
Projectile: hollow steel armour piecing high explosive round.
276 37mm Armour Piercing Tank Round
439 37mm Army Projectiles early marking system.
440 37mm Army Projectiles late marking system.
441 Japanese Army arsenal marks.
586 37mm land service rounds with partially sectionised cases: Type 1 Anti-Tank Gun, Type 94 Anti-Tank Gun, Type 94 Tank Gun & Type 97 Anti-Tank Gun.
