In the third-tier 'dream world', the Wiseman (Scott Glenn) presents Baby Doll with her weapons, one of which is a nickel plated engraved M1911A1 pistol with spare magazines (and small jewelry attachments). In the real world, a blued M1911A1 is used by Baby Doll (Emily Browning). Blue (Oscar Isaac) uses an M1911A1 with a bright nickel finish and pearl grips in the brothel. Baby Doll's handgun has a 1911-style MSH (main spring housing) as opposed to the standard 1911A1 MSH. The handgun also appears to have an ambidextrous thumb safety and the mag release catch on the opposite side (as Emily Browning uses the weapon left handed). Blue's pistol appears to be a Springfield Armory or an Auto Ordnance 1911 judging from the slide serrations angle. Also, black M1911A1 with what seems to pearl handles can also be seen in the extended version of the film in the hand of gangster.
Behind the Scenes
Flintlock Pistol
During the trench battle with the World War One German Zombie Soldiers, Rocket (Jena Malone) uses a combination of bayonet and single shot Flintlock Pistol. She uses the pistol as a club in hand to hand combat, which is probably the most practical use for the antiquated weapon in that battle.
Behind the Scenes
Walther PPK
Blondie carries what appears to be a Walther PPK in a thigh holster, but she never draws or uses it.
Rast-Gasser 1898
An Austrian Rast-Gasser 1898 revolver is seen in the hands of the German courier who tries to flee with the map.
Glock 19
Amber (Jamie Chung) carries what appears to be Glock 19 as her sidearm. As she seems to always be the pilot in the group, she most likely wouldn't need anything more than this. In the film she is only seen firing it from the cockpit of the bomber to dislodge an Orc. In some promotional material, Amber is seen holding the handgun as well.
Behind the Scenes
Unknovn Revolver
Unknovn revolver is seen in a policeman's holster.
Submachine Guns
Heckler & Koch MP5K
When she's finished using the K3 Machine Gun, Blondie (Vanessa Hudgens) switches to a Heckler & Koch MP5K with an SEF trigger group, a small red dot sight and a flashlight.
Heckler & Koch MP7A1
Baby Doll (Emily Browning) uses a suppressed Heckler & Koch MP7A1 with a tiny red dot sight, a flashlight, and two magazines taped together during the assault on the dragon's lair.
Heckler & Koch UMP45
In all of the missions in the dream, Rocket (Jena Malone) carries Heckler & Koch UMP45 with a SureShot reflex sight, a foregrip, and a flashlight. It is suppressed during the mission into the Dragon's lair, however an enormous muzzle flash can be seen when she fires it.
Behind the Scenes
Rifles
Colt M4A1
An M4A1 with rails, a SureShot reflex sight, and a flashlight is used by Sweet Pea (Abbie Cornish). The M4A1 is fitted with a suppressor during the hunt for the dragon's baby.
Springfield M1903A4
The Wiseman (Scott Glenn) uses an M1903A4 Springfield sniper rifle in the trenches of World War I, when he explains how the Germans are reanimating their dead with clockwork mechanisms and steam power.
Mauser Gewehr 1898
Undead World War I German soldiers armed with Mauser Gewehr 1898 rifles. These appear to be rubber prop versions based off the rifle.
Karabiner 98k
An undead World War I German soldier attacks Blondie (Vanessa Hudgens) in the trench with a Karabiner 98k rifle with its bayonet mounted. These rifles are most likely rubber prop versions.
Short Magazine Lee-Enfield (SMLE)
As the girls walk past the British Soldiers during World War I, the British Soldiers are carrying SMLE No1. Mk III rifles.
Shotguns
Remington 870
In the battle with armed automatons, Sweet Pea (Abbie Cornish) uses a tactical Remington 870 Shotgun with ghost-ring sights, Surefire dedicated forend weaponlight, door breaching muzzle brake, and Knoxx Specops stock. Production stills clearly show "KNOXX" written on it.
Behind the Scenes
Machine Guns
Daewoo K3 (mocked up as FN Minimi SPW)
During the dream set during World War One, Blondie (Vanessa Hudgens) carries a Daewoo K3 light machine gun fitted with a rail forearm and vertical grip (the machine gun is most likely supposed to be the FN Minimi SPW). In the extended cut of the film, she is seen emptying the machine gun at the charging zombie soldiers before she abandons it for her MP5K as soon as they reach the trench.
Maxim MG08
Undead German soldiers manning a Maxim MG08 Machine Gun are taken out by the Wiseman.
During the trench battle, Baby Doll uses a Lewis Gun to shoot down the escaping zeppelin.
Oversized M134 Minigun
One of the Demon Samurai giants is seen opening fire on Baby Doll with an oversized Minigun that's based on the handheld version of the M134 Minigun. An oversized Minigun is seen also mounted on the right arm of the "Bunny Rabbit Mech".
Other
SMAW
The same giant Samurai uses a rocket launcher that appears to be based off a SMAW. The launcher has a dragon's head in the front and is just as oversized as his Minigun.
Model 24 Stielhandgranate
During the World War I action sequence, Rocket (Jena Malone) picks up a Model 24 Stielhandgranate from a dead Zombie German soldier and uses it to take out several zombified German soldiers.
Auto Cannon
An automatic cannon is mounted on the left arm of the "Bunny Rabbit" Mech that Amber uses to shoot down an attacking Bi-plane.
Modified MAC-10
When Baby Doll and the girls battle robots guarding a bomb on a train heading for a city, the robots appear to be using energy weapons based off the modified MAC-10 seen used in Blade II.
Rocket Pod/Missiles
The Huey that Amber flies in the third dream has two missiles on each side.