The Browning M1919 is seen with some World War II-era American armored vehicles and with the University Selection Team's Alvis Saracen APC.
MG34
The MG34 is seen with World War II-era German tanks used by Oarai Academy and Kuromorimine Girls Academy in the movie.
Type 91 Light Machine Gun
The Type 91 Light Machine Gun is seen with Duck Team's Type 89 I-Go. It's likely seen with Chi-Ha-Tan Sumida M.2593 or Type 91 armored vehicles sent to pick up CHT/some OA students after their tanks were knocked out during the finals match with UST.
Type 97 Light Machine Gun
Anteater Team's Type 3 Chi-Nu and Chi-Ha-Tan Academy's Type 97 Chi-Ha's and Type 95 Ha-Go's have the Type 97 light machine gun as a secondary weapon. While the Type 3 Chi-Nu only have one machine gun on the hull, the Type 97 and 95 have two, one on the hull and one on the turret rear. It's likely seen with Chi-Ha-Tan Sumida M.2593 or Type 91 armored vehicles sent to pick up CHT/some OA students after their tanks were knocked out during the finals match with UST.
Pravda High School's Soviet tanks, the T-34/76, T-34-85, IS-2, and KV-2, are all equipped with a Degtyaryov DT as a secondary weapon.
Breda Modello 38
The Breda Modello 38 is seen with Anzio High's lone Carro Veloce CV-35.
Maxim Machine Gun
A single shot of the command tent shows a "Motor Scout" parked next to it. This 1889 quadricycle carried a .303 Maxim machine gun and shield, 1000 rounds of ammo and 120 miles of fuel, making it the first armored fighting vehicle. It was designed and built by British manufacturer Frederick Reginald Simms, but never entered service: it was, however, the ancestor of wheeled armored cars.
AK-630
The AK-630 CIWS is seen on Pravda's lone Zubr-class LCAC that's piloted to bring back the Pravda students/tanks/gear from their match with the UST.