Dr. Steven Cogswell testified Tuesday that Tracy Calloway was shot five times while in his car near his home on Trailwood Drive in 2019.
Gary Cross is facing a murder charge. Three other men are due in court next month with the same charge.
There were 63 shell casings found at the scene with bullets going in all directions, including into a nearby porch.
Dr. Cogswell said the fatal shot was to the left side of the forehead and was made by a rifle shot. He said rifle wounds are much more damaging, and this one destroyed the front part of the victim's brain.
Other shots were from a medium caliber handgun, he said.
Two were to the side and one to the right upper arm.
There was also testimony on Tuesday from the general manager of the Speedway on E. Third Street.
He furnished video of a visit to the convenience store several hours before the afternoon shooting.
Video showed apparently the same gray minivan as was involved in the shooting at one of the gas pumps. Some occupants of the van went inside and were caught on video.
A detective was to testify about that evidence later.