The main protagonist of the film, FBI ASAC (Assistant Special Agent in Charge) Anthony 'Hub' Hubbard (Denzel Washington) and several of his fellow FBI agents carry SIG-Sauer P226 pistols as their standard sidearms.
One weapon used by the Army during their occupation is the Beretta 92FS pistol (standing in for the military M9). One soldier can be seen holding one on Hubbard's decoy, and another is presumably the weapon General Deveraux uses to kill Tariq Husseini (Amro Salama). Also, it's difficult to tell (because of the light), but it appears that the terrorist in the safehouse who collects the pizza box (with bomb) also has a Beretta lying on the table.
Both the FBI agents and many N.Y.P.D. officers are seen carrying Remington 870 shotguns fitted with top-folding stocks. One of these shotguns is wielded by Agent Frank Haddad (Tony Shalhoub) during the hostage situation at the school.
Another weapon wielded by many of the FBI Agents is the Ithaca 37 riot model. Agent Frank Haddad (Tony Shalhoub) carries one of these shotguns during the raid on the CIA safehouse.
During the opening scene in which a team of American black ops soldiers capture the Sheik, they use Colt 9mm submachine guns (RO635) which appear to be fitted with C-More sights. For some reason, the Colt SMGs sound suppressed when they are fired, even though they clearly do not have sound suppressors attached.
During both bus incidents, officers of the NYPD's Emergency Services Unit can be seen carrying Heckler & Koch MP5A3 submachine guns fitted with Surefire forearms and flashlights, as per norm with SWAT-issue MP5s. FBI HRT members can also be seen carrying MP5A3s fitted with laser pointers and red dot sights during the raid on the terrorist safehouse.
Curiously, the FBI's MP5A3s have the "Navy"-style lower receivers and Surefire forearms when they are advancing up the stairs, but when they enter the terrorists' apartment and begin firing at them, the MP5s suddenly have the older-style SEF lower receivers and lack the Surefire forearms. It is likely that the MP5s used prior to entry are airsoft replicas.
Heckler & Koch MP5A3 (9x19mm) with Navy trigger group and Surefire dedicated forend weaponlightError creating thumbnail: File missingAn NYPD officer with a Heckler & Koch MP5A3 during the incident on MTA Bus #4399.Error creating thumbnail: File missingFBI HRT advance up the stairs to the terrorist safehouse with their MP5A3s at the ready. The officer on point has a Remington 870 shotgun.Error creating thumbnail: File missingHeckler & Koch 9x19mmError creating thumbnail: File missingAn HRT officer opens fire upon the terrorists. Notice that with the one on the left, his MP5 is now missing the Surefire grip, and it also has an SEF rather than a Navy lower receiver. It seems he changed weapons at some point...or, it's just a continuity error.Error creating thumbnail: File missingThe HRT officers at ease after clearing the apartment
Heckler & Koch HK94A3 (mocked-up as MP5A3)
At least one of the MP5A3 submachine guns used by an FBI HRT member during the safehouse raid is actually a Heckler & Koch HK94A3 carbine mocked up as an MP5A3 (judging by the all-metal lower receiver).
Error creating thumbnail: File missingA Heckler & Koch HK94A3 converted to a resemble an MP5A3, with a chopped barrel and converted to auto, with a third firing position added to the lower receiver. This may be one of the actual screen-used guns from Air Force One (unconfirmed).Error creating thumbnail: File missingFBI HRT officers fire upon the terrorists. The operator on the right has what appears to be an HK94A3 with a chopped barrel (judging by the lower receiver, if you enlarge this picture to its full resolution).
IMI Uzi
During the hostage situation at the schoolhouse, the terrorist holding hostages can be seen wielding an Uzi as he paces about. Despite having the responding police and FBI personnel out-gunned, he's still easily taken down when Hubbard catches him off guard. One of the terrorists in the safehouse raid is also seen using an Uzi. This is a slight cultural irony, as the Uzi is primarily produced in Israel, and is being used by Arab terrorists.
During the Bus 87 incident, there is a short clip of the NYPD's ESU snipers getting into position with Savage 10FP sniper rifles fitted with Harris bipods.
When the HRT team raids the terrorist safehouse, one of the terrorists engages the FBI in a shootout using an AKM assault rifle, though is inevitably taken down, shooting blindly and so rapidly that he hits one of his own comrades who gets in the line of fire. As with most of the AKMs used in Hollywood, this is most likely to be a full-auto conversion of an Egyptian-made Maadi ARM.
The M16A2 assault rifle features prominently in the movie; almost every soldier involved in the occupation of Brooklyn is seen carrying one. A notable point in the film is that when Maj. General William Deveraux (Bruce Willis) is describing what the occupation will entail, he distinctly mentions the "M16A1 assault rifle", though the U.S. military had switched to the M16A2 years prior to the events in the film, and indeed the M16A2s are by far the most common rifles in the movie. It is also possible that many of the prop weapons used in the movie are semi-automatic AR-15 A2s, standing in for the M16A2 (since they're never fired).
It appears that some MGC M16 replica assault rifles are used by the U.S. Army soldiers in the movie. Some may be modified to look like M16A2s by adding A2-style handguards and A1-style birdcage flash hiders, but it's hard to tell.
Throughout the film, it is possible to see many soldiers carrying XM177 look-a-like carbines. They all have long, bulky flash hiders, which tends to characterize the civilian copies of the XM177, like the one seen below. So these are probably some semi-automatic copy standing in for the military-spec XM177E2.
Error creating thumbnail: File missingCommercial CAR-15 semiautomatic rifle - 5.56mm. This is strictly a semiautomatic civilian copy of the XM177 style of rifles. The flash hider is a smaller diameter copy of the XM177 and has no sound suppression qualities and is permanently welded onto the barrel to make it legal length for over the counter gun store sales.Error creating thumbnail: File missingU.S. soldiers entering Brooklyn; the soldier in the woodland camo BDUs is carrying a semi-automatic copy of an XM177 (note the long flash hider, similar to the rifle in the picture above).Error creating thumbnail: File missingA suspect is questioned; behind him, it is possible to see the flash hider of a mock-up XM177 being aimed at him from a soldier who is out of frame. The soldier in the background also has an XM177-type rifle.
Heavy Weapons
M203 Grenade Launcher
Throughout the movie, it is possible to spot an XM177-type carbine fitted with an M203 grenade launcher in the hands of soldiers. It appears to be the exact same prop weapon being reused multiple times in different scenes.
In several scenes, Humvees and Cadillac-Gage Commando APCs can be seen with M60 machine guns mounted on them, most notably when General Deveraux is giving his press conference about the declaration of martial law and when the Army crashes the FBI's raid on the Redhook chop-shop.
When the Army crashes the FBI's raid on the Redhook chop-shop, one of the Commando APCs can be briefly seen with a Browning M3 heavy machine gun on the roof.
During the raid on the Redhook chop-shop, one of the terrorists inside uses the distraction created by the arrival of the Army to pull an M26 hand grenade, the detonation of which provokes the soldiers outside to open up on the shop with everything they have, and Hubbard and Husseini barely escape the onslaught.
