With the exception of Lt. David Poole (Denis Leary) all the protagonists are armed with Colt Model 715s built up as M16A1s with A1-style triangular handguards. The ARVN Soldiers and C-123 airmen also utilize the Colt Model 715. They are fitted With A1-style buttstocks, pistol grips, A1 birdcage flash hiders, handguards and forward assists.
At one point, the rifle carried by Harvey Ashford (Doug E. Doug) changes from a Colt Model 715 to a different rifle, possibly a Colt AR-15A2 Sporter II. This rifle has triangular handguards, an A1 style pistol grip, and possibly an A1 style buttstock. The barrel is not visible though, so the rifle can't be thoroughly identified.
Error creating thumbnail: File missingColt AR-15A2 Sporter II, early model with A1 upper receiver and magazine removed - 5.56x45mmError creating thumbnail: File missingHarvey Ashford (Doug E. Doug) snickers while holding his rifle. He was previously holding a Colt Model 715, but it switched to a different rifle in this scene. It's possibly a Colt AR-15A2 Sporter II since it has the same upper receiver as an M16A1, but has a flat "slab side" lower receiver. This gun also has triangular handguards, A1 style pistol grip, and possibly an A1 buttstock.
Norinco Type 56
The Norinco Type 56 is used by all NVA soldiers in the film. Some of them are also fitted with AKM-style slant compensators.
The NVA use a DShK heavy machine gun with anti-aircraft sights to shoot the C-123 carrying the protagonists. The crew then aim it at the protagonists as they bail out, but are not allowed to fire on them.
