During the raid on the Ark, Kanuka Clancy can be seen armed with an AMC Auto Mag as her main weapon, using it to destroy numerous BEL-1999 Caldia guard robots en-route to the Ark's main control room.
Assault Rifles
Howa Type 89
Japanese Ground Self-Defense Force soldiers at the beginning of the anime can also be seen armed with Howa Type 89 rifles.
Shotguns
Remington 870
Officers of the Special Vehicle Unit (SVU) can be seen armed with Remington 870 shotguns with high-capacity magazine tubes for use when not aboard their labors. At the climax of the anime, Noa Izume uses her Remington 870 to shoot out the onboard computer of the rampaging Type Zero labor with Kanuka trapped in the cockpit.
Machine Guns
Yakushev-Borzov Yak-B
Among the JGSDF units deployed to stop the rogue experimental labor at the beginning of the anime are several AH-88 "Hellhound" attack helicopters, each one armed with a chin-mounted four-barrel gatling; this appears to be a scaled-up Yakushev-Borzov Yak-B, increased in size to at least 20mm.
Rocket Launchers
Howa 84RR
At the beginning of the anime, JGSDF soldiers can be seen engaging a rogue experimental labor (the manned robots the anime takes its name from) using, among other weapons, Howa 84RRs.
The Type 98 "Ingram" labors used by the SVU are armed with massive 37mm revolver cannons as their sidearms, their design drawing heavily from the four inch-barreled Colt Python revolver, though on a much larger scale. The weapon has the Colt logo on the grip replaced with the Chrysanthemum seal, which is the de-facto seal of the Japanese government and royal family, and is stored in a compartment in the labor's lower right leg when not in use. One drawback of the weapon is that the pilot has to exit the labor in order to manually reload it, spare rounds also being stored in the same leg compartment.
Riot Cannon
In addition to the revolver cannons mentioned above, the Type 98 labors can also use 90mm pump-action riot cannons which resemble massively scaled-up Remington 870 folding stock shotguns with high-capacity magazine tubes. These weapons are typically employed in situations where additional firepower is required, most notably during the Ark raid. Its folding stock design resembles the ones used by the Franchi SPAS-12.
Unknown Flare gun
Noa starts the Ark's emergency floor purging system with a device referred to as a "percussion revolver;" this is obviously incorrect, since the device does not seem to be a revolver at all; it looks to be a muzzle-loaded weapon closer to a flare gun.