Bryan Mills (Liam Neeson) takes a custom tutone Beretta 92FS off of a prostitute trafficker and uses it when escaping from the facility at the construction site.
When Bryan later confronts the slaver he "spoke" with on the phone, he kills several of his men and takes one of their factory black Beretta 92FS pistols, which he uses for a good duration of the film.
Taurus Millennium Pro
When Bryan Mills (Liam Neeson) infiltrates a party held by the slavers, one of the men who captures him carries a black Taurus Millennium Pro PT111, which he takes and uses until it runs empty.
Bryan Mills (Liam Neeson) takes a factory tutone SIG-Sauer P226 off of a guard on the boat and uses it until it runs dry.
SIG-Sauer GSR Revolution
One of the Arab guards on the boat carries a stainless SIG-Sauer GSR Revolution, which is taken by Bryan Mills (Liam Neeson) until it runs dry.
Heckler & Koch MP5K
The Arab guards on the boat are armed mainly with Heckler & Koch MP5Ks with the foregrips removed. Bryan Mills (Liam Neeson) disarms a guard of one and briefly uses it until it runs empty. NOTE: While this is an MP5K variant, it is not made by H&K. Turkey has an HK licensed production facility, and produces these guns from the factory with no handguard. They are imported in to the US legally as the AT-94K (made by MKE), but in semi-automatic only form. Since the ship and its crew are from Turkey, and the AT-94K is a Turkish-made firearm, they would likely be easier to obtain for the crew.
IMI Micro Uzi
One of the Arab guards on the boat is seen using an IMI Micro Uzi with a folding stock and a suppressor before being shot through a door window by Bryan Mills (Liam Neeson).
SIG-Sauer P239
Jean-Claude (Olivier Rabourdin) retrieves an older model SIG-Sauer P239 from under the sink in his bathroom when Bryan Mills (Liam Neeson) comes to his house and holds it on him at the dinner table. When he tries to shoot him, he discovers Bryan previously unloaded the gun and throws the ammunition in his face, chastizing him for not recognizing the weight difference between a loaded and unloaded gun after being behind a desk so long.
M1911A1
One of the slavers in Paris uses a nickel plated M1911A1 to fire at Bryan Mills (Liam Neeson) after he steals a girl from the facility.
Glock 17
The bodyguard of Patrice St-Clair who fails to kill Bryan Mills (Liam Neeson) "quietly" is seen using a Glock 17. It is likely a rubber prop, since it is never fired and quickly thrown away.
Smith & Wesson 5906
When Bryan Mills (Liam Neeson) confronts the Albanian slavers in the apartment building, one of them tries to draw a Smith & Wesson 5906 from the small of his back, but is soon killed by Bryan.