The SIG-Sauer P226 is the preferred sidearm of Red Troop and is used throughout the series. It is frequently seen holstered whenever the team are wearing their counter terrorist gear, but is normally only used for undercover work.
SIG-Sauer P225
Jamie (Jamie Draven) can be seen using SIG-Sauer P225 as his sidearm in several episodes, even though this pistol is a dated design with a smaller magazine capacity than the P226s and P228s which Red Troop usually uses on the show. The use of this pistol in "Communication" (Episode 2.1) is rife with continuity errors. Firstly, Jamie can be seen holding the pistol below decks on the boat when earlier he was using a larger P226 whilst climbing aboard. Secondly, Henno (Ross Kemp) draws a P225 from his holster and clears it at the end of the episode, despite the fact that he was previously using the similar, but more modern, P228.
SIG-Sauer P228
In some episodes, the smaller SIG-Sauer P228 are used by Red Troop.
Beretta 92
In "Dead is Forever" (Episode 2.6) one of the rebels, uses what appears to be an original Beretta 92 during a mock execution and a ransom video. This particular gun features plain grip panels, and a stepped slide (it narrows in thickness just ahead of the chamber) indicating that it is one of the first 1000 or so pistols made before the design was changed to the familiar profile.
Beretta 92FS
In "Dead is Forever" (Episode 2.6) one of the rebels can briefly be seen with a Beretta 92FS. This is not the Beretta 92 seen being used at other points in the episode, as noted by the finger step on the trigger guard.
CZ 75B
One of the rebels in "Dead is Forever" uses a CZ 75B during a mock execution. The weapon misfires, prompting the user to say "Damn these cheep Czechoslovakian weapons."
Heckler & Koch USP
Heckler & Koch USP pistols are seen in some episodes, usually in the hands of the antagonists.
Smith & Wesson Model 60
Several of the terrorists on the boat in "Communication" (Episode 2.1) can be seen using Smith & Wesson Model 60 snub nose revolvers.
A Walther P99 can briefly be seen in "The List" (Episode 2.4) as the pistol being used by the sleeper assassin Levi (Simon Gregor).
Submachine Guns
Heckler & Koch MP5A3
The standard-issue weapons for the SAS unit Red Troop in the TV show are Heckler & Koch MP5A3 submachine guns, which are always seen with Surefire fore ends and tactical flashlights as well as the SEF-style lower receiver. These weapons are typically used in Red Troop's domestic hostage rescue missions.
The other SAS unit, Blue Troop, also use identical weapons, as do many Metropolitan Police SO19 (now CO19) officers throughout the show.
Heckler & Koch MP5KA1
Heckler & Koch MP5KA1 submachine guns are used by a number of the French special forces soldiers in "Communication" (Episode 2.1). The MP5KA1 is a version of the original MP5K designed for concealed carry (it lacks the H&K dioptre sights in order to avoid getting snagged on clothing when being drawn quickly from beneath a jacket).
Heckler & Koch MP5SD3
Red Troop also makes use of the suppressed Heckler & Koch MP5SD3 in "What in the Name of God" (Episode 2.5) when Red Troop invades the stronghold of a Christian cult terrorist group to capture their leader.
IMI Uzi
Several of the French special forces soldiers in "Communications" (Episode 2.1) are armed with IMI Uzis.
IMI Mini Uzi
The IMI Mini Uzi machine pistol appears in several episodes being used by the bad guys..
PPSh-41
A PPSh-41 can be seen briefly in the hands of one of the Georgian soldiers in Episode 2.6, "Dead is Forever".
Assault Rifles
AKM
AKMs are a common weapon used by terrorists on the show.
AKS-74U
One of the French special forces soldiers can be briefly seen with an AKS-74U in "Communication" (Episode 2.1).
Colt AR-15 Sporter-1
Colt AR-15 Sporter-1s are seen frequently on the show in the hands of Red troop as a stand in for M16s. They can be recognised as Sporter-1s by their screw type pivot rather than push pin pivot, which is visible in some shots. The rifle is particular prevalent in "Dead is Forever" (Episode 2.6) where it is the source of continuity errors where Henno (Ross Kemp) and Jamie (Jamie Draven) switch between using SP1s and M16A2s throughout the episode.
Colt CAR-15
CAR-15s are a common weapon used by Red troop, and can be seen used by multiple characters in "Something to Do with Justice" (Episode 1.6). These CAR-15s are most likely either mock-ups or commercial copies, as the flash hiders are too long for E1 rifles, but lack the grenade ring found on later E2 rifles.
Colt M16A1
Some of the cult members in "What in the Name of God" (Episode 2.5) use unmodified M16A1s.
Colt M16A1 (with M16A2 hand guards)
Red troop make use of M16A1s fitted with A2 type handguards on several occasions for oversees missions where more range is required.
Colt M16A2
Genuine M16A2s are also used by Red Troop, alongside the mock A2s based on M16A1s listed above
Heckler & Koch HK33A3
Several of the French special forces soldiers in "Communication" (Episode 2.1) carry Heckler & Koch HK33s.
Whenever Red Troop requires sniper support, the snipers are typically armed with Accuracy International Arctic Warfare rifles in 7.62x51mm NATO, with the majority of the main characters using one at one point or another. This rifle was used by the British army, under the designation of L118A1.
Machine Guns
FN Minimi
Red Troop is frequently seen using the FN Minimi for support during missions overseas.
Browning M1919A4
The rebels in "Dead is Forever" (Episode 2.6) use a Browning M1919A4 fitted with a tripod on the roof of a bunker.
L7 GPMG
Being the standard machine gun of the British Army, the L7 GPMG is used on multiple occasions by the SAS on the show. It is also occasionally used by terrorists on the show.
RPD
An RPD can briefly be seen in the hands of a Georgian soldier in "Dead is Forever" (Episode 2.6).
Shotguns
Remington 870 Police Folder
Some of the SO19 soldiers that appear at the end of "Communication" (Episode 2.1) carry what appears to be Remington 870 Police Folders with extended magazine tubes.
Heavy Weapons
Cobray CM203
Red Troop's M16s and CAR-15s are often fitted with Cobray CM203 37mm flare launchers to stand in for 40mm M203 grenade launchers.
M72 LAW
Henno (Ross Kemp) uses an M72 LAW to destroy a machine gun nest in "What in the Name of God" (Episode 2.5).
RPG
One of the Rebels in "Dead is Forever" (Episode 2.6) can be seen carrying an RPG-7.