Doomsday is a 2008 science fiction action film written and directed by Neil Marshall, who wrote and directed the 2002 film Dog Soldiers. As is customary with many British filmmakers, Marshall utilized actors from his earlier movie to star in his current one, evidenced by the fact that nearly the entire cast of Dog Soldiers appears in this movie.
The following weapons were used in the film Doomsday:
Major Eden Sinclair (Rhona Mitra) uses a custom suppressed Walther P38 as her main handgun during the capture of the slaver's ship. Later on Eden's Walther P38 is used by Sol (Craig Conway) during the highway chase scene.
Single Action Army
Richter's assistant, Afro Girl (yes, that is her name in the credits) (Eloise Cupido) wields a nickel plated Single Action Army revolver.
Vektor CP1
DDS soldiers are shown using a modified version of the Vektor CP1 pistol. Their version has an extended ported barrel, making the pistol resemble the FN Five-seveN, and a module under the barrel which holds both a light and laser. The laser turns on when the trigger is depressed, but this is most clearly seen when Eden uses it during daylight.
During the assault on the slaver ship a guard carries a Armscor BXP submachine gun. This weapon was selected due to the scene being filmed in South Africa and being readily available to South African Armorers. The weapon is only briefly seen.
Rifles
Enfield L85A1
L85A1 assault rifles are used by British soldiers during the initial outbreak of the Reaper Virus (circa 2008) which would almost be correct (they would have the upgraded L85A2s). Upon close inspection, the rifles seem to be Umarex Airsoft rifles with the muzzle flashes, bolt movement, and flying brass casings digitally inserted later, but they did a good job on many of the scenes. What is odd is that the L85A1 rifles have a tiny Union Jack flag sticker on them which usually only appears on the airsoft guns.
Customized L42A1 Sniper Rifle
A British sniper stationed on the wall snipes an infected man with an L42A1 bolt action sniper rifle in a plastic thumbhole stock with a elevated cheek rest and fitted with a Parker Hale bipod.
Vektor CR-21
Most of the DDS agents carry Vektor CR-21 assault rifles fitted with sound suppressors, flashlights, and laser sights. In the early part of the film, DDS agents carry CR-21 rifles with the original South African optical sight. During the mission in the badlands of Scotland, the DDS Soldiers use CR-21s that have SUSAT optical sights mounted.
Vektor R5
One of the guards of the slaver ship that's docked in the harbor carries a Vektor R5 with stock folded.
Heckler & Koch G36C
Soldiers at the Government Headquarters in London are seen with Double Eagle Airsoft Heckler & Koch G36C rifles.
Shotguns
Browning BPS
A blonde woman, bathing in the cast-iron tub aboard the ship, uses an Browning BPS shotgun with extended magazine tube and pistol grip.
Sawn-Off IZh-27 Over & Under Shotgun
Richter (Jeremy Crutchley), the trafficker in Scottish slave labor, uses a sawn-off Russian IZh-27 Over & Under double barreled shotgun to kill his business associates (whom he thinks betrayed him) and to hold DDS Agent John Michaelson (Tom Fairfoot) hostage.
NeoStead 2000
A NeoStead 2000 shotgun fitted with a flashlight is used by Chandler (Rick Warren) and then Eden Sinclair (Rhona Mitra) during the sweep of the abandoned hospital. The shotgun is used to blast a hole in the elevator ceiling and cut the cable. In the DVD extras, the director Neil Marshall claims that this is the only movie so far that has featured this unusual South African Pump Shotgun.
Cobray Street Sweeper
Miller (Chris Robson) uses a Cobray Street Sweeper during the crashed APC scene. What makes this confusing is that this scene was filmed in South Africa and one would expect the armorers to favor the better made Armsel Striker shotgun over the low-end Cobray Street Sweeper. One theory is that it is an older version of the Striker which had a key style that was eventually copied by SWD/Cobray for the Street Sweeper, but as far as the film goes, the shotgun more closely resembles what we now know to be the Street Sweeper and not the Striker, despite the fact it's in South Africa pointing towards the Striker.
Machine Guns
Vektor SS-77 Machine Gun
Instead of the British Army issued L7A2, the trooper on the top of the armored vehicle is using a Vektor SS-77 GPMG. This is because the sequence in question was filmed in South Africa so armorers used what was at hand.
Twin Barreled Sentry Guns
The British army in the story, abandons manning the wall about five years after the northern lands were sealed off and have been using motion sensor activated Sentry Guns to destroy anything that moves. Sgt. Norton mentions that the guns only wreak havoc on the 'local wildlife' since they haven't had a human target for twenty years, just as the guns focus on and destroy a rabbit. The guns themselves are just fabricated props and not based on any real world firearm or auto cannon.
Vektor MG-4
During the hospital scene, the DDS troops pass a Vektor MG-4 version of the Browning M1919A4 machine gun. It's mounted on what looks to be an anti-aircraft tripod and the debris of twenty five years of neglect.
General Dynamics GAU-19/A (Mock-Up)
A mock-up of a General Dynamics GAU-19/A gatling gun is mounted on the door Super Frelon chopper and seen prominently when the helicopter flies away carrying Dr. Ben Stirling (Darren Morfitt) and Cally (MyAnna Buring).
Other Weapons
Defense Technologies 1315
British soldiers fire CS gas and smoke grenades at the crowd from atop the quarantine wall. Though difficult to clearly see, they are single shot launchers with twin pistol grips, strongly resembling the Defense Technologies 37mm Gas Gun.
Silicon Foam Grenade
Sci fi prop "Silicon Foam" grenades are used during the escape from the hospital to enable the DDS soldiers to survive an elevator drop by encasing them in foam. Miller (Chris Robson) refers to them as "Silicon Foam Grenades" during the initial meeting with Major Eden Sinclair.
Fragmentation Grenade
A fabricated Prop Sci Fi Fragmentation Grenade is used when Carpenter releases on inside the APC after his throat has been slashed by a savage starved girl.
High Explosive Grenade
Bandoleers of these long silver fabricated HE grenades are seen on the armory table and also carried by Sgt. Norton throughout the film. They are most prominent during the castle escape when Norton retrieves his bandoleer from the castle armory and starts blowing things up. The grenades are fabricated Sci Fi Props.