The XM16E1 assault rifle are used by the soldiers of the 1st Battalion, 7th Cavalry Regiment including Lieutenant Colonel Hal Moore (Mel Gibson), First Lieutenant Charlie Hastings (Robert Bagnell), Second Lieutenant Jack Geoghegan (Chris Klein), Sergeant Ernie Savage (Ryan Hurst) and most United States Army soldiers. Later on the film during the Battle of Landing Zone X-Ray, Joe Galloway (Barry Pepper) uses one as well. These were actual XM16E1's used on the film for the heroes.
M1 Carbine
A Korean war era M1 Carbine is carried by the South Vietnamese (ARVN) interpreter dressed in tiger stripe fatigues. He appears in the scene in which the NVA scout is captured and interrogated. Viet Minh soldiers also use them against the French during the intro.
M60 machine gun
The M60 machine gun is used by several US soldiers. Various door gunners use them as well.
Colt M1911 pistol
A Colt M1911 is used by Command Sergeant Major Basil Plumley (Sam Elliott) as his main weapon since he prefers the .45 to the XM16E1, which he calls a "Piece of Plastic". It is anachronistic to see the first model of the M1911 being used by Plumley since the M1911 was replaced in 1924 by the improved M1911A1 which was the sidearm of the US Military in the Vietnam War, World War 2 and the Korean War. It could be that the M1911 was used to make Plumley more "Badass". As if a Sergeant Major that fought against a entire regiment of heavily armed NVA and a Vietcong Battalion armed only with an M1911A1 was not badass enough.
Colt M1911A1 pistol
A Colt M1911A1 is seen in the holster of LTC Hal Moore and most of the soldiers of the 1/7CAV that appear in the movie.
M26 Hand Grenades
In several scenes, U.S. soldiers can be seen with M26 hand grenades strapped to their pouches.
PPSh-41
The NVA and the Viet Cong use PPSh-41s submachine guns during the intro sequence and the rest of the movie.
Genuine AK-47s
During the movie, soldiers of the North Vietnamese Army (NVA) use genuine AK-47s with milled receivers.
The AK-47s used in the movie were built by the Movie's Armourer Mike Papac.
M79 grenade launcher
Various US soldiers can be seen carrying M79 grenade launchers in a few scenes. Specialist Galen Bungum(Blake Heron) uses one since he is the grenadier of Sergeant Savage's squad.
MAS-36 Rifle
In the opening scene where the French soldiers are ambushed during the Indochinese War, various French soldiers use MAS-36 rifles.
Smith & Wesson M-13 Aircrewman
The .38 caliber revolver pulled out by MAJ Bruce "Snake Shit" Crandall (Greg Kinnear) is most likely a Smith & Wesson M-13 Aircrewman, an unsuccessful lightweight aluminium-cylindered revolver designed for US military flyers. This was part of what was generally a badly thought-out push to make things from aluminium in the 1960s, also resulting in the M551 Sheridan's lightweight aluminium armor- which could be penetrated by machine gun fire- and a number of disasterous fires on warships with aluminium superstructures.
GE M134 Minigun
A pair each of GE M134 Miniguns are seen mounted on the gunship Hueys that rip apart PAVN soldiers at the climax of the film, and one is also on display on a table near the beginning of the movie.
M1928A1 Thompson
As the American soldiers are heading off for battle you can see a South Vietnamese soldier holding up an M1928A1 Thompson with a 30-round magazine.
Browning M1919A4
Two Browning M1919A4s can be seen mounted on French jeeps on the intro sequence.
MAT-49
Various French Soldiers use MAT-49 submachine guns during the opening Scene. Various NVA and VC use them during the rest of the movie, probably scavenged from French and South Vietnamese troops during the Indochina war.
RPG-2
An NVA soldier fires an RPG-2 (Vietnamese made version was known as the B-40) at American soldiers.
SKS rifle
Several Viet Minh soldiers and NVA soldiers use SKS rifles during intro sequence and during the Battle of Ia Drang.
Mosin Nagant M44 Carbine
During the intro sequence a Viet Minh soldier can be seen with a Mosin Nagant M44 carbine.
Karabiner 98k
A Viet Minh soldier during the intro sequence and a Vietcong soldier later on can be seen using Karabiner 98k rifles.
It should be noted that acording to one of the Armorers of the film, Steve Karnes, the Kar98ks used in the movie came from Israel and were chambered to 7.62mm NATO.
M1A1 Bazooka
A Viet Minh soldier uses a varient of the M1 Bazooka, the M1A1 Bazooka with one forward grip and a modified rear sight to destroy a French jeep during the intro sequence.
While it seems that a Viet Minh soldier using a Bazooka could be a anachronism, the French army widely used the M1A1, M9A1, and M20 bazookas during the Indochina War. The Viet Minh widely used scavanged French weapons during the Indochina War, and the PAVN and Vietcong also widely used them during the Vietnam War.
Degtyaryov DP-28 machine gun
During the scene where the men of the 1st Cavalry division perform a bayonet charge against a NVA position(which actually didn't happen in real life) a small crew of PAVN soldiers man a DP-28, a varient of the Soviet Degtyarev light machine gun.
Type 67 Grenade
A Chinese Type 67 hand grenade is thrown at the 1st Cavalry Division's position.
RPD Light Machine Gun
During the Battle of Ia Drang, one PAVN soldier can be seen carrying an RPD Light Machine Gun.
Czech ZB26
An ZB26 is used by a Viet Minh machine gunner during the intro sequence in the Indochina War. Acording to Steve Karnes, The Movie's Armourer, the ZB26 used in the movie was sold to the Chinese and converted to 7.62x39 later in it's life. It also has Chinese Characters on the side of the receiver.
MG34
When the American Soldiers charge the NVA position, a two man crew of NVA soldiers man an MG34 Light Machine Gun before they get killed by the Huey Helicopters. One NVA soldier also mans another MG34 in the same scene.
Browning Hi-Power Pistol
During the Intro of the Movie set during the Indochina War, a French Officer uses his Siderarm, a Browning Hi-Power pistol, to kill several Viet Minh soldiers before being killed himself.
The use of the Browning Hi-Power pistol by the French Army in the movie is a error. The Armourers couln't get French MAB pistols and since Hi-Powers were at the region the Armourers used those Hi-Powers instead.