Combat experience in Iraq has changed the way the U.S. Army trains its troops to use their rifles, machine-guns and pistols. Since two thirds of the casualties are caused by roadside bombs and gunfire from ambushes, troops have had to learn to use their weapons reflexively. This is a special kind of shooting, and the army has usually had its hands full just teaching the troops the basics. This was especially the case for combat support troops, who are not expected to use their weapons often, if at all. But in Iraq, any combat support troops outside a base quickly learn that combat is a very real possibility. Thus, by late 2003, more elaborate and intensive weapons training became a necessity. 

Trainers quickly discovered that teaching reflexive fire was more complex and time consuming than expected. First, the troops, especially non-infantry, had to get more practice on the basics. This included how to quickly clear jammed weapons, fast reloading, and the need to clean weapons regularly and keep them zeroed in (adjust the sights, especially the new high tech ones, so that you hit what you believe you are aiming at.) Then you have to make sure everyone has their basic marksmanship skills down. This is the traditional rifle range stuff, with concentration on aiming the rifle and pulling (or squeezing) the trigger properly. Then you get into practicing firing your weapon from non-standard positions (sitting in a hummer, or from the back of a truck, or from any number of other odd positions that always seem to be the norm in combat). Another aspect of reflexive firing is switching weapons quickly, and still getting off accurate fire. Many troops carry a pistol, as well as a rifle, and you need to practice switching quickly from the rifle (which may be jammed, or out of ammo), or machine-gun, to the pistol, for those situations when you have no choice. The training also includes firing one handed, with either hand (to reflect being wounded, or in a really awkward position). But, above all, its a matter of lots of practice. Not just for the initial reflexive firing course, but regular practice after that.