M4A1 Carbines are used by many Recon Marines in the series, including Corporal Josh Ray Person (James Ransone) and Brad 'Iceman' Colbert (Alexander Skarsgard). Some are outfitted with the M203 Grenade Launcher. The M4s seen in the series all have full quad rails, and some had attachments like PEQ laser modules and and optics. Most are stock with iron sights. They also seem to have some type of aftermarket pistol grips.
The M16A2 appears in the hands of numerous characters, including Lieutenant Nathaniel Fick (Stark Sands). The M16A2 is currently being phased out by the newer M16A4, but because the mini-series depicts the Invasion of Iraq in 2003, the M16A2 remained the standard rifle of most Marine units.
American Marines, most notably Lance Corporal Trombley (Billy Lush), carry the paratrooper variant of the M249 SAW throughout the series. The M249 is also seen mounted on Marine UH-1 helicopters.
Several Browning M2HB machine guns are mounted on the Marines' Humvees, and are often used in conjunction with the Mk. 19 grenade launchers to assault Iraqi positions.
The M203 grenade launcher is usually carried by the Marine team leaders and officers, including Sergeant Brad Colbert and Lieutenant Nathaniel Fick. In episodes 5 and 6, the M203s are used to launch blue smoke grenades in an attempt to prevent accidental shootings at roadblocks.
Kalashnikov rifles are used by Iraqi soldiers, civilians and even American Marines, in particular one platoon commander, Captain Dave 'Captain America' McGraw (Eric Nenniger).
PKM machine guns are used by the Iraqi forces throughout the miniseries, sometimes mounted on tripods.
Recoiless Rifles
After the recon Marines successfully capture a strategic bridge in Episode 5, the surrendering Syrian irregulars can be seen abandoning recoiless rifles and heavy mortars.