In the film's opening, Danny Archer (Leonardo DiCaprio) carries a sub-compact Glock variant, which is most likely a Glock 26 and hands it over when stopped by Rambo (Ato Essandoh). The Glock is loaded with what appears to be an extended magazine. He later has the pistol confiscated when he is arrested for smuggling diamonds into Liberia.
An H&K USP Compact is used by Danny Archer (Leonardo DiCaprio) throughout the film. He purchases the weapon from a dealer at a bar for a couple hundred dollars after having his Glock 26 confiscated while smuggling diamonds He uses it to kill about several rebels and many of Col. Coaztee's men. He later gives it to Solomon near the end of the film when he tells him that he will stay and hold off Col. Coetzee's men so Solomon can make his escape.
Several close-ups of Archer's USP Compact reveal that it has an exposed hammer (the Compact, unlike the full-size USP, has a spurred hammer as standard), which suggests the gun might be the P10 variant, or otherwise a specially modified weapon.
Captain Rambo of the R.U.F wields a Smith & Wesson Model 629 revolver when he confronts Danny and demands his weapon. There is a slight possibility the revolver could be a Smith & Wesson Model 686, however the barrel looks about 5" which would likely make it the 629 model.
Error creating thumbnail: File missingS&W Model 629 Revolver .44 Magnum with custom gripCaptain Rambo holds a Smith & Wesson Model 629 on Danny while he unloads his Glock 26
Chamelot-Delvigne Model 1873
A Kamajor guerilla point a French Chamelot-Delvigne Model 1873 11mm revolver at Solomon and Maddy Bowen (Jennifer Connelly) thinking he is R.U.F. Note: The revolver may be a M1874 which is the same gun with a fluted cylinder. It isn't seen again in the movie.
R.U.F. Captain Poison (David Harewood) carries a Browning Hi-Power which frequently uses to kill slaves at the mine whom he sees trying to steal diamonds.
The South African mercenaries carry an unusual Colt CAR-15 variation that does not appear to be a factory-standard gun. They have the receivers of M16A2s (which would normally suggest Colt Model 725s), but they also have 10-inch barrels with GAU-5/XM177-style flash hiders. They were most likely custom-assembled for the film from the parts of various AR-model rifles. It should be noted that similar rifles can be seen in Black Hawk Down, and Bapty & Co. supplied the weapons for both this film and that one.
Besides their unusual combination of features, the mercenaries' CAR-15s also feature camouflage paint and accessories such as Surefire weaponlights and M68 Aimpoint scopes. Archer uses one at the end of the film after killing its owner, buying time for Solomon and Dia to escape before succumbing to his wounds.
The vast majority of the Revolutionary United Front (R.U.F.) rebels and the Sierra Leone Army regulars are seen using Norinco Type 56-1 assault rifles (Chinese AKS-47/AKMS clones), which can be recognized by their folding stocks and hooded front sights. Archer briefly uses one to execute an R.U.F. rebel who tries to flee him on the bridge. Dia can be seen using one while participating in his first massacre as an R.U.F. guerrilla (he is also forced to use one to kill a prisoner while undergoing indoctrination).
Error creating thumbnail: File missingNorinco Type 56-1 7.62x39mmA crate full of Chinese Type 56-1 (AKMS) assault rifles about to be issued to newly recruited R.U.F. members.An R.U.F. guerrilla stands guard over slaves at a mine with his Chinese Type 56-1 assault rifle in hand.Dia taking part in a massacre with other R.U.F. child soldiers; all are armed with Chinese Type 56-1 rifles.Sierra Leone Army soldiers preparing to confront the R.U.F.; the muzzle of one soldier's Type 56-1 is clearly visible, showing the hooded front sight (a defining characteristic of Chinese AKs) in detail.R.U.F. rebels firing their Type 56-1 AKs at the mercenaries' Hind helicopter when their stronghold is attacked.
AK-47
There are also some original Russian-made AK-47s (as opposed to AKM copies or Chinese Type 56s, which are far more common in most Hollywood films) seen in the hands of R.U.F. rebels throughout the movie. Most of them are the Type III milled receiver variation, but a close-up of one of the AKs reveals that it has the stock mounting bracket of the slightly older Type II variant. The child soldier who tries to kill Benjamin Kapanay (Basil Wallace) uses one, and Archer himself wields a Type III AK-47 during the mercenaries' assault on the mine, which he uses to off many of the rebels.
Error creating thumbnail: File missingAK-47 7.62x39mm (this is the same Type II variation seen in the screenshot just below)At the R.U.F.'s camp, a soldier stands guard with an AK-47. Note the mounting bracket for the stock, which suggests that this is the Type II variation (manufactured in the early 1950s) - the others seen in the film are Type IIIs, which have a different design.Error creating thumbnail: File missingAn R.U.F. child soldier shoots at Benjamin Kapanay with a Type III AK-47. The other Child Soldier has a Type-56.Error creating thumbnail: File missingArcher running with an AK-47 captured from one of the rebels during the attack at the mine.
Heckler & Koch G3
Many of the R.U.F. guerrillas and Sierra Leone Army soldiers are seen carrying older-specification Heckler & Koch G3s with wooden handguards & stock though without seeing the rear sight. This is quite true to real life; the G3 was standard-issue to the Sierra Leone Army for many years (though they later began purchasing Type 56 AKs from the People's Republic of China), and many fell into the hands of the R.U.F. during the civil war.
Several Sierra Leone Army soldiers can be seen with M16A2 assault rifles, and many of the South African mercenaries use them as well.
Error creating thumbnail: File missingM16A2 5.56x45mmSierra Leone Army personnel rounding up suspected militants; the barrel of an M16A2 is visible in the foreground.Archer, Solomon, Maddie, and other reporters ducking gunfire as the press convoy comes under attack; an SLA soldier in the foreground has an M16A2.South African mercenaries ambush the R.U.F.; one of them clearly has an M16A2 with a 20-round magazine.
Machine Guns
DShK Heavy Machine Gun
Throughout the film, DShK heavy machine guns are seen mounted on the R.U.F.'s "technical" vehicles.
During the scene where Archer and Soloman are crossing the bridge, an RPK light machine gun can be seen leaning against a wall at the R.U.F. guard post.
Several Sierra Leone army soldiers can be seen carrying Sterling L2A1 submachine guns during the scene where Archer is arrested for diamond smuggling.
Error creating thumbnail: File missingSterling L2A1 submachine gun - 9x19mmA Sierra Leone Army officer inspects Archer's goats for diamonds with his Sterling L2A1 slung over his back.
Other
RPG-7
RUF rebels regularly wield RPG-7's, particularly during the battle of Freetown. One rebel tries to shoot at Archer and Maddie's vehicle with one during the press convoy ambush, but misses.
Error creating thumbnail: File missingRPG-7 40mmAn R.U.F. rebel prepares to fire his RPG-7 at a Sierra Leone military roadblock in Freetown.Another view of the same scene.
GIAT F2 20mm Cannon
The helicopter used in the assault appears to be the Mil MI-24 "Superhind", which is seen with chin mounted 20mm cannon. The standard cannon for the "Superhind" is a French GIAT F2.