The Delta operators mainly wield the M727 and M733 variants of the Colt Commando. The M727 variant is identified by its A2 upper reciever and 14.5" barrel with the cutout for mounting an M203 grenade launcher; the M733 has the shorter 11.5" barrel. Staff Sgt. Daniel Busch (Richard Tyson) is the first Delta member on screen, and also the first soldier we see carrying an M727. All Delta members carry M727s and M733s, fitted with various accessories such as Aimpoint scopes and surefire flashlights. Master Sgt. Gary Gordon (Nikolaj Coster Waldau) can be seen carrying an M733 featuring a camouflage paint scheme and a sound suppressor, which is then used by Chief Warrant Officer Michael Durant (Ron Eldard) to pick off several more Somalis before running out of ammunition and being overwhelmed.
Delta Customs
The Deltas arm themselves differently from the Rangers by using customized Colt Model 727 and 733 rifles as opposed to longer, heavier M16A2 rifles. Many are fitted with such accessories as Aimpoint scopes, surefire flashlights (with the pressure switch taped to the handguard with 100mph tape), some of them have camouflage paint schemes, and some of them are fitted with 14.5" barrels with M203 cuts (M727).
(note - some of the pressure switches were rendered useless as as the delta operators fast roped in from the black hawks, the friction from the 3inch ropes burnt straight through the connecting cable, meaning that the flashlights and in some cases, the radios, failed to function properly.)
Rangers
While the Rangers are armed almost entirely with M16A2 rifles, Cpt. Steele (Jason Isaacs) uses an M733 rifle noted by the 11.5" barrel, with nothing modified or changed. A field medic is also seen using an M733, presumabley because he would need a lighter, more versatile weapon to move quickly to wounded soldiers.
Delta Sniper
Master Sgt. Gary Gordon uses an M733 rifle with the camo paint, scope and a light, but his is fitted with a sound suppressor. Shughart gives this rifle to the wounded Chief Warrant Officer Michael Durant, who uses it before it runs out of ammo.
CAR-15
Some of the Deltas are seen using Colt Commando CAR-15 carbines with the original long type muzzle break, which are also heavily customized. There is a high possibility they are built from several Commando types so a definite I.D. isn't certain unless the armorer can verify it.
Colt M4 carbine
Hoot seems to use an Colt M4 carbine rifle with the same customizations and paint job as the Commando rifles when doing solo operations in Somalia, noted by its removable carry handle. He uses it to shoot a wild boar from a chopper, and is chastized by Cpt. Steele (Jason Isaacs) for keeping the weapon's safety off in the baracks. It is noted as an M4, the burst rifle varient because the M4A1, the full-auto varient had not been issued yet. The M4A1 would begin issue around 1995 or so. One of the Deltas is also seen using an M4 carbine during the operation itself.
A bit of anachronism here, both the M4 and M4A1 entered service in 1994, a year after the events of this film (in 1993), so the M4 should technically not be in Hoot's hands. The probable reason was the fact that most of the earlier M16 Carbines are hard to come by, so they needed something to fill that gap.
M60 machine gun
Specialist Shawn Nelson (Ewen Bremner) can be seen carrying an M60 machine gun machine gun as his standard weapon. Some of the Somalians can be seen using them as well.
FN Minimi
Several Rangers can be seen carrying FN Minimis throughout the film, standing in for the M249-E1 SAW. It is also the weapon used by Specialist Lance Twombly (Tom Hardy) to accidentally deafen Nelson when he fires it too close to his head.
M16A2
Staff Sgt. Matt Eversmann (Josh Hartnett) leads his Rangers armed, like most of them, with an M16A2s.
M14
The M14 Rifle is seen being used by Sergeant First Class Randy Shughart (Johnny Strong), most notably when he and Master Sgt. Gary Gordon are covering the second crash site. His M14 sports a camouflage paint scheme and an M68 Aimpoint scope. It was noted that the actual SSGT Shughart actually used a M21 with a M68 scope, although the movie armorer used an M14 to supplement this.
M16A1
M16A1 rifles are seen in the Somali arms dealer's shop and one militia member is seen loading up one. At one point, Rangers can be seen watching a portion of the film The Jerk where a madman is trying to shoot the protagonist using a scoped M16A1.
CETME
Spanish CETME rifles are seen among the weapons in the arms dealer's shop, many of which are taken by the militia to combat the U.S. forces. They are not Heckler & Koch G3s, most notabley because they have a simple fixed sight instead of a rear sight spindle.
Heckler & Koch G3A3
The local militia arm themselves with, among many other weapons, Heckler & Koch G3A3 assault rifles.
PKM Light Machine Gun
A PKM light machine gun is seen resting on a table in the Somalian arms dealer's shop.
SVD Dragunov
When Hoot (Eric Bana) is in the Somali town, he passes the arms dealer, who has an SVD Dragunov on display.
RPK
One of the Somalian fires on Mike Durant's Black Hawk armed with an RPK light machine gun. Its blonde furniture indicates it could be a foreign copy. The machining divots in the receiver could help indicate its origins as well.
(the milled receiver, blonde wood, and the fact that the selector is in semi seem to suggest it is an Arsenal Bulgarian RPK, probably a US-made semi-auto variant)
RPG-7
The Russian manufactured RPG-7 features prominently in the film as it is the weapon which brings down a pair of Black Hawks. In one scene, a projectile from an RPG-7 strikes the driver of one of the deuce and a half trucks in Lt. Colonel Danny McKnight (Tom Sizemore)'s convoy and fails to detonate, impaling the luckless soldier instead.
A full stock Norinco Type 56 is used by a Somalian to whack Mike Durant in the head. It has a slanted AKM syle muzzle break added on.
Norinco Type 56-1
Nearly all of the Somali gunmen are armed with the Norinco Type 56-1 assault rifle, which is a Chinese derivative of the AKS-47/AKMS. They are identified by the hooded front sights, which only Chinese Kalashnikov rifles have.
AKS-74U
Mo'alim (Razaaq Adoti), the Somalian militia leader, carries an AKS-74U as his weapon of choice, first seen picking it up and inspecting it before heading into battle, then firing a burst into the air to break up the mob attacking one of the surviving Blackhawk pilots before announcing that he was to be taken alive as a prisoner.
SPG-9 Recoilless Rifle
At one point in the film, Somalis begin to bombard the building the majority of the Rangers and Deltas have taken cover in with mortars and an SPG-9 recoilless rifle. A group of Deltas soon kill the gunners and then turn the weapon against the Somalis, killing several with one shot before destroying the weapon with a thermite grenade.
While the Cobray CM203 37mm launchers are fitted on most of the Ranger's M16A2 rifles, a couple of actual M203 grenade launchers attached to M16A2s are seen, the most notable of which is Specialist John Grimes (Ewan McGregor) who assists Delta in taking out a technical that has them pinned down, missing the first shot before destroying the vehicle with a High-Explosive Dual-Purpose (HEDP) grenade from his M203.
M1911A1
We see the M1911A1 pistol in the hands of the Delta operators as their sidearm of choice. As the two Delta snipers attempt to secure the second crash site they are forced to draw their M1911A1 pistols as the overwhelming Somali forces close in on them. Another Delta operator can be seen practicing with an M1911A1 near the beginning of the film.
The Beretta M9 pistol is seen a few times in the film in the hands of Rangers, and members of McKnight's convoy. Mainly it is seen in the hands of Maddox in the Humvee. McKnight himself carries his M9 sidearm around as a proper means to defend himself.
Heckler & Koch MP5A3
Chief Warrant Officer Michael Durant (Ron Eldard), a Black Hawk pilot, is armed with a Heckler & Koch MP5A3 with a slim forearm and uses it to defend himself after he's shot down. The MP5 was briefly issued to helicopter crews as a personal defense weapon (PDW), but was discontinued in this role when it was determined its' 9mm ammo lacked sufficient stopping power against armor-wearing or drug-crazed enemies, as was the case in Somalia. The guns is also briefly used by SFC Randy Shughart before being killed by the overwhelming militia.
In the book and real life, the weapons were actually MP5Ks. They were referred to as "Skinny Popper, a reference to the men's nickname for the Somalis.
Browning M2HB
The Browning M2HB heavy machine gun is fielded by both the U.S. Army HMMWVs, the U.N. APCs, and the Somali militia in the film. The opening shots of the film feature Somali militiamen slaughtering a gathered crowd at a food distribution center with the powerful fifty-cal.
GE M134 Minigun
During the slaughter of the crowd, The U.S. forces hovering in the MH-60 aren't cleared to fire the GE M134 Miniguns mounted on their Black Hawk. Pylon-mounted miniguns, mounted alongside 2.75 rockets, are also carried by the AH-6 Little Birds and rain lead in several scenes.
DShK Heavy Machine Gun
Several vehicle mounted Russian DShK heavy machine guns appear in several scenes of the film.
M72 LAW
An Army Ranger, Lieutenant Tom DiTomasso, can be seen taking out a "technical" with an M72A3. The M72A3 was a Post Vietnam improved model of the M72 Rocket, and the last variation used by the U.S. Army. Upgrade versions (up to M72A7) of the LAW are being fielded by the U.S. Navy and USMC as recently as 2007.
Remington 870
While never used on screen, Sgt. Sanderson (William Fichtner) can be seen with a customized Remington 870 Express Magnum (standing in for an 870 Police Magnum) slung over his right shoulder. A pistol grip (minus the folding stock) is used in place of the full stock. This same setup is used on a short 870 by Charlie Sheen in the movie Navy SEALs.
M67 Hand Grenade
While loading up for the assault, Hoot (Eric Bana) picks up M67 fragmentation hand grenades. Sgt. Sanderson is later seen throwing one into a window to take out a Somali who has him and the Deltas and Rangers pinned down.
M7A2 Hand Grenade
An M7A2 CS gas grenade is seen sitting next to the M67 fragmentation hand grenades Hoot picks up.