The Imperial Japanese Army Air Service improved the Type 98 flexible machine‑gun and developed the Type 1 flexible machine‑gun. The Imperial Japanese Navy acquired the same licensed MG 15 blueprint and produced its own derivative, designated the Type 100 flexible machine‑gun.
All of them trace back to the German MG 15 and share nearly identical core construction. The army and navy each adjusted ammunition specifications and minor component details, then issued separate official designations for their own service. As a result, these weapons are very often confused with one another.
Army lineage: Type 98 flexible machine‑gun (based on MG 15) → improved into Type 1 flexible machine‑gun (Te‑3).
Navy lineage: built from the original MG‑15 base design, directly designated Type 100 flexible machine‑gun.
Haha, classic inter‑service rivalry between the Japanese Army and Navy.
Early variants fired 7.92 mm Mauser ammunition, while later models were rechambered for domestic Japanese 7.7 mm rounds.
Here is some technical information about the gun from the JACAR archives. I did my best to translate to English and fill in the missing data.
Technical Specification
Type 98 Fixed Machine Gun
Type 98 Flexible Machine Gun
Experimental Type 98 Fixed Machine Gun (Model 2)
Model 3 (Te-3) Single Barrel
Model 3 (Te-3) Twin Barrel
Caliber (mm)
7.92
7.92
7.92
7.92
7.92
Length (mm)
1180
1078
950
944
1086
Velocity (m/sec)
750
750
750
750
750
Rate of Fire (rpm)
1100
1100
1000
1000
2200
Operation Type
GO/SR
GO/SR
GO/SR
GO
GO
Feed Mechanism
DB
DRSD
DB
DRSD
DRSD
Capacity (rounds)
250 / 500
75
250 / 500
75
100
Weight (kg)
10.1
7.2
11.2
9
15
Mag Weight (kg)
3.8 / 7.6
4.25
3.8 / 7.6
4.45
5.9
All variants listed here used 12.8 gram 7.92mm cartridges.
Abbreviations:
GO/SR - Gas-Operated, Short Recoil
GO - Gas Operated
DRSD - Double Row Saddle Drum
DB - Disintegrating Belt
Notes: Type 98 Fixed Machine Gun: First prototype. Finished by end of March. Planned. (Kokura Arsenal) Type 98 Flexible Machine Gun: Mid-March: Second fundamental trial. Endurance trial carried out. Transferred to mass production research (Nagoya Arsenal). Experimental Type 98 Fixed Machine Gun (Model 2): First prototype. Unfinished by end of March. Planned. (Nambu) Model 3 (Te-3) Single Barrel: First prototype. Finished by end of March. Planned. (Kokura Arsenal) Model 3 (Te-3) Twin Barrel: Mid-March: Third trial conducted. Durability confirmed. Afterwards, transferred to mass production research (Nagoya Arsenal).
