The M4A1 Carbine is the standard issued weapon of the US Army soldiers in the film, many of which are customized with optical gunsights, lasers, and foregrips.
Pvt. Reno Flake (Patrick Carroll) disarms an Iraqi grandfather of his Norinco Type 56 when he attempts to defend his family with it. He then murders the whole family off-screen.
AKM
Al Qaeda terrorists who kidnap Pvt. Angel Salazar in revenge for the death of the Iraqi family are armed with AKM rifles.
Beretta M9
The standard issue sidearm of the US Army soldiers is the Beretta M9. Private Reno Flake (Patrick Carroll) uses his to threaten Sgt. Lawyer McCoy(Rob Devaney) when he refuses to take part in the rape of the Iraqi girl.
Pvt. Reno Flake(Patrick Carroll) uses a Browning M2HB to kill a pregnant Iraqi woman when her husband tries to rush through a check point in an attempt to reach a hospital quickly.