Shuka Karino is briefly seen handling a Norinco Type 54, presumably taken from a slain opponent, in "First Game". Several more are seen in the hands of various players in "Ignition" and "Fireworks", and in those of Eighth Clan members in "Hardness" and "Eighth" (which is, in spite of the name, the seventh episode).
The actual firearm that Kaname Sudo is given in "First Game" is a Beretta 92FS; he later uses it (or rather, several others attained via his Sigil ability) against Shuka; he creates and uses more of them during "Ignition" and "Fireworks", primarily using them to shoot out security� cameras.
Two Gyro Heads (and a third player of unspecified affiliation) are seen with Ingram MAC-10s in "Ignition"; several Eighth Clan members also use them in "Hardness". Their size is depicted rather inconsistently, ranging from being more or less accurate to the size of a small assault rifle between shots.
Rein Kashiwagi's main weapon is a Remington 700PSS. She carries it around in a large case on her back, first drawing and firing it in "Fireworks". Another Remington is wielded by an unnamed sniper in "Aquarium", though it is ultimately never fired.
Ryuuji Maesaka's primary weapon is an RPD, with both Maesaka and his gun initially appearing in "Ignition". Sudo uses his Sigil to create two others during "Fireworks", using them against Ichirou Hiiragi (and later a third during "Aquarium"); he also notably uses his Sigil to create overpressure ammunition for the weapon, to aid in dealing with Hiiragi's armor.
Both Rein and Sudo use M67 Hand Grenades throughout "Fireworks" (hence the episode's name); like the M84s, they're a purchasable item in the in-game shop, and are depicted as being somewhat underpowered (releasing no apparent shrapnel), though they're also somewhat oddly painted black. Several more are used by the Eighth Clan, starting in "Hardness", and yet more are used by Hiiragi in "Eighth".
Rein and Sudo use M84 Stun Grenades in "Ignition" and "Fireworks", while Shuka uses one in "Eighth"; they're apparently a rather popular buyable item in the in-game shop. They're depicted more as simple light-producing devices than as actual stun grenades; in one noteworthy scene, sets one off in his hand, somehow not mangling or burning it in the process.
