Doomsday

The weapons seen in this movie are:

Vektor SS-77 machine gun

An SS-77 GPMG is seen used by the British Soldiers at the start of the movie. These weapons were used for the movie instead of the standard L7A2 as they are currently being used in Iraq/Afghanistan.

SA80

At least one live SA80 was used in the film for a scene when Soldiers fire apon paniced civilians.

The SA80's in this movie are airsoft guns hence the Union Jack sticker at the corner of the butt area. Again, these airsoft guns are used in the movie for the same reason above.

Neostead shotgun

Used in the abandoned hospital

Armsel Striker

An Armsel Striker is seen momentarily durring the crashed APC scene.

Unknown sawed off over/under shotgun

an Unknown over/under shotgun is used to take a DDS agent hostage and is then accidentally discharged into the hostages head.

Winchester 1200

The Woman bathing in the cast Iron tub abord the ship has what looks like a pistol gripped Winchyester 1200.

Prop Sentrygun

A prop Sentrygun is used durring th Border wall scene. it is shown messily destroying a rabbit that gets too close to the wall.

M1919A4?

Its possible an M1919A4 is seen in the abandoned hospital mounted on a tripod but is not used.

GAU-19/A

A 3 barrel .50 BMG Gattling Gun is mounted on the SuperFrelon chopper at the end half of the movie.