Bureau of National Security Agent Alex Scott (Owen Wilson) carries a Smith & Wesson 5906 as his sidearm throughout the film. Towards the end of the film, Rachel (Famke Janssen) is seen using one as well, likely the same gun.
Glock 17L
BNS Agent Alex Scott (Owen Wilson) is seen using a Glock 17L while carrying the pilot during the opening scene.
Zastava M70
Russian soldiers at the beginning of the film are seen using Zastava M70 assault rifles, both full stock M70B1s and folding stock M70AB2s, noted by their folding grenade launcher sights. In reality, Russians have been using 5.45x39mm AK-74s since the 1980s.
M60E3 machine gun
The door gunner on the escape helicopter at the start of the film covers Alex (Owen Wilson) with an aircooled M60E3 Machine Gun.
Smith & Wesson 3913 "Ladysmith"
A BNS gadget maker tests out a super-spy bullet proof vest by firing a Smith & Wesson 3913 "Ladysmith" at it at point blank range. The bullet then deflects off the vest and hits him back.
Beretta 92FS
Beretta 92FS pistols appear several times in the film, typically in the hands of nameless thugs. Kelly Robinson (Eddie Murphy) notably uses one (loaded with blanks) to shoot at Rachel (Famke Janssen) before he informed it is a test.
This is a Taurus of some kind, I think a PT99 (it seems to have the tall rear sight). -MT2008
Carlos (Gary Cole) wields two specially modified Beretta 92FS pistols with compensators, barrel weights, laser pointers, and 20 round magazines, which he uses to fire bursts on Gundars' men on the bridge.
Heckler & Koch MP5A3
Many of Gundars' (Malcolm McDowell) men carry Heckler & Koch MP5A3s (with both SEF and Navy trigger groups) while making the exchange for the "Switchblade" stealth plane. When Kelly Robinson (Eddie Murphy) comes to save Alex Scott (Owen Wilson), he takes an MP5A3 off of one of the men Alex had knocked out earlier and uses it to fire on the men. A continuity error present is that the gun used is seen with both an SEF and a Navy trigger group.
GOOF - On the poster for this movie Eddie Murphy is seen posing with a MP5A3.
The one he´s holding has the Navy trigger group, but if you look closely at the bottom of the grip you can see that this has a plate in it and is not hollow as the real firearms grip - this is clearly an airsoft gun used for promotional photos. (The most common airsoft version has a small electrical motor that feeds the gun hidden in the pistol grip, therefor a small plate is used at the end of the grip to keep the engine in place).
Heckler & Koch MP5K
Heckler & Koch MP5Ks are seen in the hands of Gundars' (Malcolm McDowell) men during the shootout on the bridge and Alex Scott (Owen Wilson) commandeers one to shoot back. A Heckler & Koch MP5KA1 without front or back sights is used by one of Gundars' men to shoot at Alex and Kelly, fitted with a sound suppressor.
AMD-65
Some of Gundars' (Malcolm McDowell) men pursuing Alex and Kelly fire AMD-65s from their cars at them. The guns are given the sound report implying they are silenced but they are not fitted with sound suppressors.
IMI Uzi
Some of the BNS agents posing as kidnappers carry IMI Uzis.
IMI Mini Uzi
Several thugs in the film use IMI Mini Uzis. Alex (Owen Wilson) takes one off a thug in the steam room and carries it with him to the top of the bridge, but is disarmed of the weapon before he can use it.
IMI Micro Uzi
An IMI Micro Uzi is used by one of the thugs in the steam room. Kelly (Eddie Murphy) throws it in the air and Alex (Owen Wilson) shoots it to cause a spark (which wouldn't happen unless he is firing FMJs) and ignite a gas main, causing a large explosion.
One of the thugs in the steam room uses an AR-15 pistol with an M4A1-style upper receiver with a removable carry handle, and features a collapsing CAR-15/M4 stock, but has a short pistol length barrel like an OA-93 or Patriot Arms pistol. The gun is fitted with a Beta-C drum magazine.
I think its a XM177E2 with the new M4 stock and beta c drums...
Calico M955A
One of the thugs in the steam room is using a Calico M955A automatic Carbine - 9mm. The 955A is an intermediate barreled automatic carbine with a telescoping stock.
Kimel AP-9
On of the thugs during the "Switchblade" plane exchange is seen using a Kimel AP-9.
Makarov PM
Rachel (Famke Janssen) tries to pick up a Makarov PM while on the top of the bridge but is ordered to drop it by Carlos (Gary Cole).
Tank Mounted Flamethrower
A Russian Tank is seen using a mounted flamethrower to attempt to burn Alex (Owen Wilson) as he carries the pilot to safety.
Spy Gadget Flamethrower
A gadget maker tests out a spy style Flamethrower as Alex (Owen Wilson) walks through the place.