Prison guards on the oil drill platform keep Beretta 92FS pistols as their sidearm. When Sean Archer/Castor Troy (Nicolas Cage) escapes from the electroshock room, he takes a guards Beretta and uses it to fire on the guards, carefully placing his shots as not to kill them. During the final firefight Archer/Troy uses a pair of Berettas, wielding them akimbo as per the standard norm of John Woo films. Jamie (Dominique Swain) picks one of these up as Archer/Troy and Troy/Archer (John Travolta) struggle in the church's courtyard, only to be misled into shooting her father in the arm. Troy/Archer then picks the Beretta up and holds it on Jamie before she digs a stilleto knife into his leg, which he ironically gave her as a gift to protect herself.
Beretta 92FS Inox
A Beretta 92FS Inox is wielded by one of the police officers during the shootout at the airport. Castor Troy/Sean Archer (John Travolta) tries to draw one to use on Sean Archer/Castor Troy (Nicolas Cage) while on the speed boat, but Archer/Troy kicks it away before he can use it.
Custom Springfield M1911-A1
Castor Troy's (Nicolas Cage) weapons of choice are two gold plated Springfield Armory M1911-A1s fitted with custom gold inlaid grips, that he keeps in two small-of-the-back holsters. Among the obvious modifications to the guns include skeletonized hammers, beavertail grip safeties, ambidextrous slide stop safeties, target sites, moderately bevelled magazine wells, and Mag-na-Ported slides/barrels. He uses them akimbo during the first major gunfight of the movie, putting a hole in the windshield the helicopter Sean Archer (John Travolta) is in and later gunning down several agents in the airport hangar. Later in the movie, when Archer has assumed Troy's identity and face, he is given these weapons by Dietrich (Nick Cassavettes). He then uses them for the proceeding gunfight as the police raid the building.
SIG-Sauer P226
Sean Archer (John Travolta) uses a SIG-Sauer P226 with a nickel slide as his sidearm in the film, using it during the film first gunfight. When he and Castor Troy (Nicolas Cage) switch faces and identities, Troy/Archer begins using the weapon, killing Dietrich (Nick Cassevettes) and another FBI agent with it before he loses it during the church's "Mexican Standoff".
Stechkin APS
A Stechkin APS machine pistol is used briefly by one of Dietrich's (Nick Cassavetes) friends to fire on police raiding the apartment building. While in the courtyard of the funeral home, Castor Troy/Sean Archer (John Travolta) uses one briefly before having it knocked from his hand. At the conclusion of the fight, Sean Archer/Castor Troy (Nicolas Cage) picks the gun up and fires a long burst at Troy/Archer after he unsuccessfully tries to kill his daughter.
Skorpion SA Vz 61
Used in the shootout at the airport by Castor Troy's brother Pollux.
Ruger Mini-14/AC556
The prison guards on the oil drill platform are armed with Ruger Mini-14s or their full auto counterparts, the Ruger AC556.
During the prison break scene, Ivan Dubov (Chris Bauer), the inmate that helps Archer/Troy (Nicolas Cage) escape from the electro-shock chamber, picks up an AC556 rifle from one of the dead guards and kills several guards before Archer/Troy stops him.
Milkor BXP
During the final firefight Castor Troy/Sean Archer (John Travolta) picks up a BXP as he flees from Sean Archer/Castor Troy (Nicolas Cage) who is firing at him.
Smith & Wesson 5906
During the final firefight stand off Castor Troy's girlfriend, Sasha Hassler (Gina Gershon) is armed with a Smith & Wesson 5906.
The thing is way too short to be a 59 series, so it's probably a 69 series. "Correct Sir that is a Smith and Wesson 6906 with a 12 +1 round capacity not a 5906.
Walther PPK
On the plane the undercover FBI Agent pulls a Walther PPK on Castor Troy.
Colt 9mm Submachine Gun
During the shootout in Dietrich's apartment, some of the FBI SWAT team members can be seen with Colt 9mm SMG rifles with reflex scopes. Used by Dietrich's sister Sasha during the shootout as well.
Unknown Revolver
During the first major gunfight in the movie. Sean Archer briefly uses a backup revolver with his Sig P226 akimbo-style. Possibly a .38 special.
Heckler & Koch MP5 submachine gun
The Heckler & Koch MP5 series of submachine guns were extensively used by FBI on numerous occasions. During the FBI's assault on Dietrich's apartment, the assault team were armed with the MP5A2, the MP5A3 and the MP5SD3 series submachine guns.
Remington 870 shotgun
A sawn-off Remington Model 870 was used by Dietrich to fend off the FBI assault team attacking his apartment.
M60 Machine Gun
During the oil platform prison escape, a helicopter with a mounted M60 machine gun chases down Sean Archer/Castor Troy (Nicolas Cage) just before he jumps off the platform.