Barkley separated his throwing shoulder during the Trojans' 38-28 loss to UCLA on Nov. 17.
"I'm 100 percent on track with my rehab program," Barkley said. "It's been a slow process. I've had to be very patient at times with the rehab that I've been doing."
Barkley wanted to go through drills, but he stuck to the plan. He has begun to ramp things up and is more on his own after having every throw, distance and velocity charted earlier in the process.
"I'm very competitive as it is, so I wanted to get out there and just fire it," Barkley said. "The plan that I've had in place, I'm still on a pitch-count. It's been pretty specific in terms of percentages of velocity and how far, even the distances I've thrown every day. I believe in the doctors and the physical therapists that have been watching over me every day.
Barkley, who measured 6-foot-2½ and 227 pounds at the combine, was asked how he would respond to those who question his arm strength.
"Look at the tape," Barkley said. "Watch the tape. You can watch the tape where I made throws in tight windows. I can make every NFL throw that you could need."
UPDATE: Barkley confirmed to The Associated Press that there was a shouting match among players in the USC locker room after last season's 21-7 loss to Georgia Tech in the Sun Bowl.
Barkley called the shouting "normal" for a football locker room, adding he and the Trojans' captains never allowed matters to escalate and the upperclassmen had things "under control."
Follow Kareem Copeland on Twitter @kareemcopeland.