The barkeeper puts down four tequila shot glasses in front of Michelle - however, she and King drink a total of eight shots before they order more.
During the chase scene, the machine gun mounted atop the HMMWV changes from the .50 M2 machine gun to a 7.62 M240B machine gun.
At Tommy's funeral, the worker is shoveling dirt in the grave when they start fighting. The worker leaves, in one shot there is the pile of dirt, two shots later the shovel appears in the dirt pile.
After Sgt. Kings flight from base after receiving his stop loss, he pulls his jeep up to a small house surrounded by a rickety wooden and wire fence. As he begins to jump the fence, the camera cuts to a new angle and the fence miraculously changes to a much sturdier (and taller) chain link fence.
When Sgt. King steals Steve's jeep the top is down. Sgt. King is in a hurry, yet when he shows up at his destination in the next shot, the top of the jeep is up. Jeep tops take at least 10 minuets of tedious work to put up, and it was sunny all day, so it could not have been put up due to rain.
During the ending sequence when Staff Sergeant King is "counting heads" on the bus, we see the newly-enlisted brothers of "Rico" and "Tommy". Staff Sergeant King was slated to return back to Iraq at the end of the month, however, if the ending sequence was the actual time that King was to return, the brothers would still be in boot camp, as Army Recruit Training is 9 weeks long, not including the Advanced Individual Training which follows Recruit Training.
The M4s shown in the film have the A2 style upper receiver, with fixed carrying handles. Only the first production run of M4s were built to this configuration, while the remainder had the A3 style upper receiver, with detachable carrying handle. The first production run M4s were a rather uncommon sight, and certainly wouldn't be used by a unit so up-to-date and well equipped as one shown in the film.
When Sgt. King is home in Texas and giving his speech, they pan the audience and show a gentleman wearing an American Legion cap with his "Medal" ribbons on the left side. It is against American Legion policy to wear anything on the left side of the cap. Ribbons, etc, shall only be worn on the right side of the cap. The only thing allowed on the left side of the cap is City and State embroidery, yet this cap was not embroidered.
The U.S. Army personnel in the movie wear the outdated DCU and BDU. At the time of the movie's filming and release, the U.S. Army wore the ACU.
The M4s carried by soldiers in the film are shown firing on full auto. In reality, only select units, such as Special Forces and the Rangers, have this feature available to them. The standard issue M4 (as well as M16A2 and M16A4) is limited to three round bursts.
When Sgt. King visits Rico, as he pushes his wheel chair out of the sun you can clearly see a bulge in Rico's t-shirt where his real arm is resting.
Sgt. King's scar miraculously heals overnight.
Despite a subsequent scene showing President George W. Bush's presidential photo, when King escapes from the MPs and steals their army jeep, the inspection sticker reads 1997. President Bush took office in 2001.
When 'Ryan Phillipe' follows the people who broke into his car and has a gun pointed to his head, you hear a hammer make a sound, yet the person has a Glock, which doesn't have a hammer.
When King is talking with the other soldier on the run in the motel, his mouth does not move for one sentence even though we hear his line.
When Brandon is fleeing to Washington and while still in Texas, there is a shot of a bus going by which is a Ride-On bus, which only operates in Montgomery County, MD.
When Michelle and King visit Rico at the Hospital Rico calls King sir and "Sarge" many times. King being a Staff Sergeant would not and cannot be called "sir" the title is reserved for officers only in the U.S. Army. He can only be called Sergeant, Staff Sergeant, and other variations of Sergeant.
During the Humvee-car chase sequence at the beginning of the film the character "Rico" has no ammo magazine in his rifle during the whole scene.