The Army Adapts in Iraq

In a pinch, often eveyone becomes an infantrymen. From DefenseLink:

Fighting the war in Iraq has transformed artillerymen into light infantrymen, a job filled with cordon-and-search operations, motorized convoys and dismounted patrols.
Soldiers from 1st Battalion, 320th Field Artillery Regiment, have accepted and excelled in their nontraditional role. The field artillery soldiers have dominated a large area throughout the city and rich farmland of Taji, performing in the role of the light infantryman and securing peace for the people of the region.

"We've captured 109 insurgents; 41 have gone to Abu Ghraib," said Lt. Col. Rafael Torres, the battalion's commander. "We've discovered 15 caches (of weapons), three of which were the biggest ever found in this area. We've taken in excess of 1,400 to 1,500 artillery rounds here recently and destroyed them."

The key to success has been intense training:

With soldiers in six different specialties making up 1st Battalion's headquarters battery, training with the right soldiers has made all the difference in effectively taking on the light infantry role.
"The 5th Special Forces group trained with us for four months solid at Fort Campbell," Torres explained, "(and) we fired more ammunition between the July timeframe until September when we deployed than the average artillery soldier has fired in his lifetime."
Some soldiers weren't sure at first about what lay ahead. "When we first found out we were going to be doing light infantry, we didn't know what to expect," said Sgt. Eden Puente, Headquarters Battery.
Training by experts in infantry tactics made a difference in the soldiers' confidence levels. "I think everybody's pretty happy about what we've been doing here so far," said Puente.