Soldiers of the 1st Platoon, Bravo Company, 25th Infantry Division "Tropic Lightning" use M16A1s, most commonly seen in the hands of Pvt. Chris Taylor (Charlie Sheen).
M16
Crawford (Chris Pedersen) is briefly seen using what appears to be an original M16 as it lacks a forward assist. It could also be an AR-15/SP1 rifle, but since he is not seen firing it, it is unknown.
Colt Model 653P
Sgt. Elias Grodin (Willem Dafoe), SSgt. Robert Barnes (Tom Berenger), and Lt. Wolfe (Mark Moses) are armed with Colt Model 653P carbine assault rifles, noted by their rounded forward assists an 14.5" barrels, as the 653Ps were 653 export models sent to the Philippines. They were probably meant to stand in (albeit poorly) for the XM177E1 or E2. It is thus anachronistic to see these in the movie, as they were not used during the Vietnam war.
M1911A1
The M1911A1 is the standard sidearm for all of the NCOs and Officers in the film. It is most prominently seen used by SGT Elias (Willem Dafoe) when he does tunnel rat duty and SSG Barnes (Tom Berenger) when he uses it to threaten a little girl in the Village to get her father to talk.
Remington 870 Wingmaster
Bunny (Kevin Dillon) uses a Remington 870 Wingmaster shotgun with open blade sights throughout the film.
M60 machine gun
The M60 machine gun, affectionately known in Vietnam as "The Pig", is fired primarily by King (Keith David) in the film. As was typical in Vietnam, the M60 is typically manned by two men, a gunner and an assistant gunner who "feeds" the ammo.
B-40 RPG
Several NVA soldiers are armed with B-40 RPG's, a Vietnamese copy of the RPG-2.
Norinco Type 56
The Norinco Type 56 is the weapon of choice of the Vietnamese troops, many of which feature "pig-sticker" under folder bayonets. They are noted as Chinese Type 56 rifles based on their hooded front sights. Only the milled receiver variant of this rifle was actually used during the war. Towards the end of the film, both Sgt. Robert Barnes (Tom Berenger) and Pvt. Chris Taylor (Charlie Sheen) are seen using these rifles, picked up from dead Vietnamese soldiers.
M79 grenade launcher
While never seen used in the film, the M79 grenade launcher is carried by several soldiers during the film, including Tubbs, a member of Red's squad.
Browning M2HB
A Browning M2HB .50 cal is seen mounted on for use on an M113 Armored Personnel Carrier after the final stand.
M72 LAW
An M72 LAW is seen strapped on top of Pvt. Chris Taylor's (Charlie Sheen) pack. It is also seen used by Barnes during the final stand.
M34 White Phosphorous Grenade
Huffmeister (Robert 'Rock' Galotti) is seen throwing an M34 White Phosphorous grenade (also called "Willy Pete" - slang for White Phosphorous) in one of the rice wells during the raid of the village. Barnes also uses an M34 Grenade to destroy one of the underground tunnels, this time yelling "Willie Pete!" when he throws the grenade.
M26 "Lemon" hand grenade
M26 "Lemon" hand grenades are seen several times as the standard issue grenade of the members of 1st Platoon.