Max (Mel Gibson) carries a sawed-off shotgun, an older model with exposed hammers (unlike the shotguns he carried in the first two movies). It's used only once in the beginning of the movie against a Bartertown guard. Max turns in his weapons as a condition of entering Bartertown, but forfeits them when he is banished for "busting a deal."
Stevens Single Barrel Shotgun
Jebediah, the Pilot's son, attempts to rob Max and the others with a Stevens Single Barrel Shotgun with some kind of expanded barrel and an M1 Carbine.
Mossberg 500AT
A sawn-off Mossberg 500AT Shotgun is seen welded by Blackfinger at the end, He racks it but doesn't shoot it.
Handguns
Mauser C96
A Mauser C96 pistol is among the many handguns that were in Max's (Mel Gibson) possession before they were confiscated from him by the Bartertown authorities. Could be the same gun that was used by Bubba from the first Mad Max.
Smith & Wesson Model 29
A Smith & Wesson 29 is amongst the many weapons surrendered by Max's on his entry into Bartertown. Note that this pistol is not Lord Humungus' piece from Road Warrior, which - besides sporting a scope - has a substantially longer barrel (8 inches on the 29 in Road Warrior; 6 inches at most in Thunderdome).
Rifles
Ruger Mini-14
A Ruger Mini-14 with a rare underfolding stock, 30-round magazine, and barrel vent is seen wielded by Ironbar (Angry Anderson) in Bartertown.
Lee-Enfield No.1 MkIII*
A Lee-Enfield is seen holstered on a Motorbike Sidecar during the train chase scene but is not used, one is also seen in the hands of a Bartertown citizen.
M1 Carbine
An M1 Carbine is seen wielded by the Pilot's son, who is also armed with a shotgun at the end of the railway line but are not fired. An M1 Carbine is also part of the tribal spear carried by Slate, the eldest of the male "waiting ones." When Savanna threatens to leave the camp, Max "borrows" it from Slate and removes the spear point affixed to the underside of the barrel. A closeup of the chamber is visible when Max chambers a round and while the manufacturer is unknown, the numbers 30 are clearly visible. Also the round chambered is very short, typical of that of the .30 Carbine round. A closeup of the muzzle is shown, as well as the rear peep sight is clear when Max shoulders the rifle.
Mauser Karabiner 98k
Carried by a man entering Bartertown at the beginning of the film.
Unknown Rifle
When Aunty is addressing the Citizens of Bartertown, there is a guard standing behind her, with an unidentifiable rifle.
Machine Guns=
M60
An modified M60 machine gun, indentified by its flash hider, is seen in the hands of one of Aunty's guards. Its possible it may be a prop.
Other
Crossbows
As with the Road Warrior, a majority of all the wasteland survivors, use crossbows as their main line of defense.
Mounted Spear Gun
During the train pursuit, one of the vehicles is seen with a mounted spear gun on it. Ironbar mans and uses one during the chase.
Multiple Guns
Some scenes have too many guns on scene, which in turn are also hard to identify.