One of the Joker's henchmen uses a 40mm grenade launcher to break a window and to fire a grappling hook on the bank's roof. They are later seen used once more by his men to fire a line between two buildings to take down a helicopter.
Beretta 92SB
A Beretta 92SB equipped with a suppressor is used by one of The Joker's henchmen, "Happy" during the bank heist to kill "Dopey". An officer is also seen pointing his 92SB at The Joker when he takes Detective Stephens (Keith Szarabajka) hostage with a shard of glass, demanding to get his one phone call.
Note: Actually, Happy doesn't appear to be using a 92FS. It has a rounded trigger guard, and seems to have more in common with a 92SB.
I haven't checked on this page in a while, but it is very obviously a Beretta 92SB-C, note the short grip and magazine shape. If I had had these shots when I made the page, I would have known this. - Gunmaster45
"Grumpy", one of The Joker's henchman in the bank heist, uses a Glock 17 to kill "Happy" in the vaults. He also uses it to hold up The Joker, suspecting he will kill him as well, only for Joker to tell him he is going to kill the bus driver. This confuses Grumpy until he is hit by a bus that smashes into the building. Several other Glocks are seen in the hands of henchmen and police throughout the film.
Glock 17 (Converted to full-auto)
The Joker (Heath Ledger) uses a Glock 17 that has been converted to full-auto, as the gun lacks the Glock 18's firing selector switch on the side of the slide. His tutone Glock is fitted with a G18's standard 33 round magazine. He is seen using it as his main weapon several times in the film. A fun fact, to make the gun sound more impressive, the report of a GE M134 Minigun is used to dub the gunfire of his Glock. Despite the extreme cyclic rate difference (roughly 1300rpm to 4000rpm), this sound fits quite nicely. For someone as bizarre as The Joker, the gun fits him well as it is very rare, destructive, stylish although in some ways impractical. The extremly high cyclic rate makes it difficult to control, although in the hands of an experienced shooter, it is all the more deadly. The armorer refered to the gun as a Glock 18, but this is less of a mouthful then "Glock 17 converted to full-auto to resemble a Glock 18". Not to mention, he likely assumed no one would know the difference anyway. The armorer also mentioned how three Glocks were used, including two converted Glock 17s and one flashpaper model for close shooting scenes where blanks are harmful.
Walther P99
Lau (Chin Han) is seen pulling a Walther P99 from his desk when Batman (Christian Bale) cuts the power in his building and fires several shots at him before all of his men are dispatched and he is captured.
Glock 26 (fictional mock up)
During Harvey Dent's (Aaron Eckhart) introduction in a trial of Sal Maroni (Eric Roberts), the crime family leader, the witness (in Maroni's payroll), Al Rossi(Michael Vieau), draws a Glock 26 cosmetically changed to look like a different gun and tries to kill Dent with it, only to discover the gun is out of working order. After dissarming Rossi, Dent identifies the gun as a "Carbon fiber... 28 Caliber, made in China." Though, admittedly, this is just movie-talk, and therefore not actually pertaining to the gun.
Smith & Wesson Model 19 Snub
The Joker takes a Smith & Wesson Model 19 Snub off of one of his men at Harvey Dent's fundraiser after Batman knocks him unconcious and uses it to hold Rachel Dawes (Maggie Gyllenhaal) hostage before shooting out the window behind him and dropping her out of it.
GE M134 Minigun
Bruce Wayne (Christian Bale) is seen using a custom built automated gun built from a GE M134 Minigun to test bullet impacts on slabs of wall to test which type of round matches the bullet he found used by The Joker to kill a police officer.
SIG-Sauer P229
Detective Stephens (Keith Szarabajka) uses a SIG-Sauer P229 as his sidearm in the film most notably during the funeral when The Joker fires at the mayor.
M16A2 rifles are used by National Guardsmen, and by some of the GCPD officers at the funeral.
M4A1 Carbine
M4A1 carbines are used by the GCPD SWAT teams throughout the film, and police snipers during the funeral. The M4A1s are seen mainly fitted with reflex sights, foregrips, and M900 Surefire tactical lights.
Heckler & Koch MP5A2
Heckler & Koch MP5A2s are used by GCPD SWAT teams and SDU teams in Hong Kong throughout the film.
A GCPD SWAT sniper scouts windows for shooters during the funeral armed with a Remington 700PSS.
Blaser 93
Blaser 93 sniper rifles are used by the GCPD SWAT snipers over looking the building The Joker is in from the neighboring rooftop. While the poor light makes them kind of hard to see, the basic shape of the rifle and the obvious straight pull bolt-action makes it easy to identify.
M1 Garand
The Joker (Heath Ledger) and his men use M1 Garand rifles during the assassination attempt on the Mayor while disguised as the officers who carry out the 21 gun salute during the funeral of Commissioner Loeb (Colin McFarlane). Since funeral procession guns are blank converted or fitted with blank adapters (they could lack both but these guns clearly fire in semi-automatic), the guns are either following the movie myth that blanks and live rounds both work in live guns, or they removed the adapters and are firing live rounds into the air for the first two volleys!
Note: Theoretically, (however unlikely) the rifles might be unmodified Garands firing grenade-launching blanks during the first two volleys.
Norinco Type 69 RPG
A Chinese Norinco Type 69 copy of the RPG-7 is used by the Joker during the armored car chase scene. He uses it to destroy a police cruiser, but fails to hit the armored car protecting Harvey Dent (Aaron Eckhart). When Batman (Christian Bale) joins the chase, The Joker fires on the armored car again, only to hit the Tumbler inadvertently (after Batman bridges his Tumbler in front of the van). The Tumbler damaged beyond viability, Batman is forced to switch to his secondary vehicle hidden within the Tumbler, the Batpod. The SWAT officer riding shotgun referred to this rocket propelled grenade launcher as a "bazooka", which meant that this officer probably did not have any prior military experience before joining GCPD.
An AKMSU is used by one of Scarecrow's men during the meeting with the Russians.
IMI Mini Uzi
One of the Batman copycats is seen using an IMI Mini Uzi to shoot at the Russians.
Ruger Mini-14
A Ruger Mini-14 is used by one of the Batman copycats who attacks the meeting between Scarecrow and the Russians. Batman twists the barrel on the rifle with his super-strength gadget before knocking him out.
During the bank robbery, the Bank Manager (William Fichtner) uses a sawed-off Remington 870 shotgun to kill "Chuckles" and fires at Joker and Grumpy, firing five shots in total. Grumpy asks Joker if he is out and when he jumps up to fire, an unexpected sixth round grazes him before Joker shoots him. After he kills his remaining men, Joker takes the shotgun for himself. He is later seen using it to gun down a traffic cop who walks up to his semi-truck and to fire at the SWAT van transporting Harvey Dent before switching to his RPG. Multiple times in the film he is seen firing the gun with one hand, which in reality would produce more recoil than shown. Since blanks produce little to no recoil, this factor doesn't present a problem in movie guns.
Remington 870
Remington 870 shotguns are seen as the standard long arms of the Gotham City Police Department. One of the Batman copycats is also seen firing one during the meeting between the Chechan and Scarecrow.
Double Barrel Shotgun
A Double Barrel Shotgun is seen wielded by one of The Joker's henchmen at the fundraiser. Bruce Wayne (Christian Bale) disarms the henchman of the shotgun and then disassembles the gun. This gun was likely selected because it is arguably one of the simplest guns to disassemble of many.
Mossberg 500
Mossberg 500s can be seen in the hands of the correctional officers on the carrier guarding both the civilian boat and the convict boat. GCPD SWAT are also seen with tactially outfitted Mossberg 500s.
-The GCPD SWAT officer riding shotgun in the armored transport isn't outfitted with a Mossberg 500. It's a Benelli M3 Super 90, just like the one Gordon uses to apprehend The Joker because he takes it from the GCPD SWAT officer who's riding shotgun.
Mossberg 590
Mossberg 590s are also seen used by the correctional officers on the carriers. 590s are also used by GCPD officers.
Benelli M3 Super 90
Comm. Gordon (Gary Oldman) uses a Benelli M3 Super 90 with a Surefire dedicated forend (which he took from the SWAT officer who rides in the front seat with him in the armor transport carrying Dent) to apprehend The Joker only seconds before he kills Batman.
Smith & Wesson M76
The Joker (Heath Ledger) uses a Smith & Wesson M76 stored in his semi-truck to fire several shots at Batman's Batpod and several civilian cars before Batman crashes and Joker ditches the gun in favor of his knife. One of Scarecrow's men is also seen armed with one during the meeting with the Russians. Like the modified Glock 17 listed above, the report of a GE M134 Minigun is dubbed over for the sound of the gun.
MAC-11
"Chuckles", one of Joker's henchmen, uses a MAC-11 during the bank robbery before being gunned down by the Bank Manager.
MAC-10
Many of Joker's men use MAC-10s through out the film. Several of the hostages towards the end of the film disguised as clowns are seen with MAC-10s taped in their hands.
Beretta PM12S
Several of The Joker's men are seen using Beretta PM12S submachine guns throughout the film.
Smith & Wesson Model 10
Several officers in Hong Kong following the SDU teams are seen using Smith & Wesson Model 10 revolvers with heavy barrels and rubber grips.
The Joker's Grenades
The Joker, a "man of simple tastes", favors his explosives. Mainly grenades. During the bank robbery, he brings a duffle bag filled with grenades including Mk 2 hand grenades, M26 hand grenades, and M67 hand grenades, which he primes in the bank goers' hands so they are forced to hold the primer handles on. Later when facing the major mob bosses during their meeting, he manages to stop Gambol from attacking by revealing many of these grenades attached to the inside of his jacket, all stringed to the ring attached to his finger.
SIG-Sauer P226
The Chechen (Ritchie Coster) and his men are seen using SIG-Sauer P226 pistols during the meeting with Scarecrow.
Colt Police Positive
After The Joker announces on the news that if Coleman Reese (Joshua Harto) isn't killed within the hour, he will blow up a hospital in Gotham, one citizen tries to shoot Reese with his old nickel plated Colt Police Positive before he is tackled by the police.
Browning M2HB
The National Guard jeeps are seen with Browning M2HBs mounted on top of them.
Unknown Revolver #1
"Chuckles" is seen holding an unknown revolver in his left hand when he is shot by the Bank Manager.
Unknown Revolver #2
One of Scarecrow's men at the meeting with the Russians is seen in the background with a revolver too far aware for clear identification.
Batpod
The Batpod is an autonomous vehicle salvaged from the Tumbler. It is equipped with mini-rocket launchers, machine guns and even two grappling hooks, notably used to bring down (or, actually up) The Joker's semi.
The mini-rocket launchers are used to clear automobiles immediately after the Batpod breaks off the Tumbler and to remove minor obstacles such as the alley garbage container. The grappling hook guns are first fired at the engine compartment of the semi and then trailing cables are secured around two street posts and then shot again to become anchored to the street. Note that this feat is next to impossible unless the initial hooks actually grab onto the semi's chassis. If they only hook onto the radiator, it would have come off instead of lifting the entire vehicle.
Bomb Gun
Pump-action gun that Batman uses to fire timed "sticky bombs"; another gadget he packs away in his utility belt.