Alice (Milla Jovovich) uses two Para-Ordnance Nite-Tac pistols as her sidearms throughout the movie. They are not normal Para Ordinance LDAs, as previously thought, as they lack the black serrations on the front of the slide, the biggest indicator of standard LDAs.
SA80/L85A1
Chase (Linden Ashby) uses an SA80/L85A1 while perched up on the "Eiffel Tower" in Las Vegas. It is fitted with a Aimpoint CompM2 red dot scope instead of the typical SUSAT scope.
PM-98 Glauberyt
Carlos (Oded Fehr) uses a PM-98 during the upgraded zombie fight in Las Vegas before running out of ammo and discarding it. It had an attachment under the barrel to set your hand on (which can also be equipped with tactical flashlight or lasersight) and a retractable buttstock. The PM-98 is a modified version of PM-84P GLAUBERYT made by Polish Fabryka Broni Łucznik Radom.
Taurus PT92AF
Mikey (Christopher Egan) carries a Taurus PT92AF as his main sidearm. He fires it at the attacking birds and in the Vegas zombie fight.
Glock 17
Claire (Ali Larter) uses a Glock 17 during the Vegas zombie fight. An Umbrella soldier also has one in his ankle holster, which he tries to shoot Alice with. Unsurprisingly, the soldier's pantleg is not large enough to cover the weapon, and during the fast cut of his draw, the cuff is shown tucked between the pistol and his leg.
Magnum Research Inc. Mark XIX Desert Eagle
As in Resident Evil: Apocalypse, L.J. (Mike Epps) carries a gold plated Desert Eagle in .44 Magnum. Strangely, he carried two in Apocalypse, yet only uses one in Extinction, possibly because he lost it in combat.
A Mini Uzi is used by a survivor in the battle with the test subject zombies in Las Vegas.
Mossberg 590 "Compact Cruiser"
As in Resident Evil: Apocalypse, Alice carries a Mossberg Compact Cruiser in her arsenal. She uses when fighting off the super zombies in Las Vegas. As in Apocalypse, she fires it one-handed. The weapon first appears about 8 and a half minutes into this film strapped to Alice's back in a cut-off commercial camo case as she pulls up to the TV station KLKB. Possible images of prop of weapon shown [here][1].
Mossberg Model 464
Claire Redfield (Ali Larter) uses a Mossberg Model 464 to try and kill a zombie on top of Mikey. The sound effect doesn't follow every time Claire cocks the weapon. It seems like for every 2 shots, we see her cock once, but when she first it off screen, we don't hear her cock again for the next shot before we see her cock again. The Mossberg Model 464 is a reproduction copy of the Winchester Model 1894 produced by Mossberg, and boasts an already drilled & tapped scope mount.
Heckler & Koch USP-9
Carlos has 2 Heckler & Koch USP-9s , with stainless steel slides. He loses one of them under the bus. In the next shot when we see him crawling under the bus, his remaining USP apparently was switched with a Taurus PT92AF.
Seen held by one of the Umbrella guards is a Beretta CX4 Storm before Alice shoots him down.
Winchester Model 1300
Carlos tells a survivor to lock and load his Winchester Model 1300 shotgun when they leave the crow infested motel. (It appears to be a Winchester due to the large burnt sienna cocking pump.) K-Mart (Spencer Locke) pulls the Winchester to blow a hole in a super zombie's head.
IMI Uzi
While she doesn't use them in the film, Alice is seen holding two IMI Uzis in the theatrical movie poster.
Smith & Wesson Model 64
One of the physcopathic survivors at the abandoned radio station can be seen with a Smith & Wesson Model 64 holding on Alice.