The following guns were used in the film War:
Rogue (Jet Li) uses a 1st Generation Walther P99 with a QPQ-finished slide. However, in one of the more glaring Hollywood firearms inaccuracies in recent memory, Rogue's P99 is neither the 9x19mm nor the .40 S&W version. Instead, it is depicted as being chambered for the 5.7x28mm round - the same round FN's Five-seveN and P90 guns use, and a round that is significantly longer than the two calibers it can be chambered for. Strangely, a Five-SeveN is seen in the film used by Benny (Luis Guzmán) when Benny and Crawford corner the plastic surgeon.
Chinese thugs use Beretta M12s to execute Yakuza at the docks.
Heckler & Koch UMP
An FBI agent was seen with a Heckler & Koch UMP during the raid at warehouse 16 and during the tea house raid. It was seen with a red dot sight attached later on.
Heckler & Koch MP5K
Chinese thugs were seen with Heckler & Koch MP5Ks when assaulting the tea house.
Yakuza and Chinese thugs were seen with Uzis in hand at the beginning of the movie and during the tea house raid.
Heckler & Koch G36K
Heckler & Koch SL8
Heckler & Koch HK33
Jericho 941 R
The Jericho 941 R was used in the movie by many of the Yakuza. One of the most notable scenes the Jericho was used in was during the shoot out at the tea house. This is the gun that Takada (Kenneth Choi) is reaching for when he is stabbed through the hand by John Crawford (Jason Statham). Crawford uses the same pistol later. Rogue (Jet Li) also picks one up from another Yakuza henchman, during the fight scene at the exotic car dealership, toward the end of the film.
COP 357 Derringer
Kira (Devon Aoki) had this as her weapon and showed it once in front of the Yakuza to show she means business.
Crawford used a Remington 870 with a heat shield, a extended magazine-tube, and the pump has a flashlight attached to it, in the beginning of the movie until Rogue shot him and made him dropped it.
A Remington 870 was seen in the hands of an FBI agent briefly with a pistol grip.
Skorpion SA Vz 61
A Chinese thug was using a Yugoslavian made Skorpion right before Crawford shot him.
Beretta 92FS made to resemble a Beretta 93R
A Yakuza member was seen with this in his hand, suppressed. It was seen with the 20 round magazine. You can tell its not a 93R due to it having a slide mounted safety, a more contoured slide as opposed to an more angler slide, and a smaller trigger guard and longer dust-cover, the opposite is true for a 93R.
One of the Chang's men, who lead the tea house raid, used a suppressed M1911 variant.