CAMP SHELBY, Miss. -- Some soldiers with the 278th Armored Cavalry Regiment know the drill.
They've trained in California and New Mexico for Iraq missions. This time, the scenery is just a little more Southern.
Between 50 and 60 percent of the soldiers deploying in February with the Knoxville-based unit are on their second or even third tour to Iraq.
The 278th patrolled the Iraq-Iran border during its 2004-05 deployment. Many of the soldiers now in Mississippi were there.
In 2007, the 1/181st Field Artillery Battalion worked security at Camp Bucca, Iraq, which is jogging distance from the Kuwait border.
Sgt. Lamar Price, 56, of Ooltewah, is on his fourth tour in the Persian Gulf area.
He went in 1991 when the U.S.-led coalition ousted Saddam Hussein from Kuwait. He went back with the 278th in 2004 and the 1/181st in 2007.
"In '91 and '04 it was kind of the Wild West over there," he said.
During his 2007 trip, the sergeant spent most of his time in the Camp Bucca prison and didn't see much of the rest of the country.
"I've heard it's much more pacified now," he said.
Most soldiers said each deployment helps better prepare them for the next. That experience is something the first-timers look to for guidance.
Sgt. Eric Tinkham, 40, of Harrison, deployed in 2004 with the 278th.
"The other night, we were out on the range and two (soldiers) thought I was asleep," he said. "And they said, 'I'm scared, I don't know if I'm ready.' I piped up and said, 'You're ready.'"
The sergeant said the new deployment would be easier on him because he knows what to expect. Much of his last deployment revolved around protecting U.S. Army convoys driving through the country.
That's nearly the entire mission for the 3,200-soldier regiment on this trip.
Col. Jeffrey Holmes, the regiment's commander, said that the mix of combat veterans and first-timers is the best way to deploy. The experience of the veterans along with the energy of younger soldiers on their first combat mission helps keep everyone focused, he said.
But with each combat tour, there is increased risk of both mental and physical injuries, a study shows.
A study published in the American Journal for Public Health showed that "soldiers with multiple deployments are more than twice as likely to report chronic pain" and "more than three times as likely as soldiers with no previous deployments to screen positive for post-traumatic stress disorder."
Each trip teaches all kinds of lessons, from how to pack your gear to spotting roadside bombs to what to do on downtime, soldiers said.
Spc. Mitchell Monroe, 22, from Chattanooga, heads into his second deployment with a better idea of what to avoid.
"I'm not taking as much stuff as I did last time," he laughed.