Karrie,

My records show a Sergeant William R. Hersey of Company B,Ware Volunteers, 50th Georgia Infantry Regiment, as being killed at Gettysburg on July 2. This was documented by an eye witness account of Lt. William F. Pendleton during the battle. Hersey's widow (Caroline) later filed for a Confederate Pension in Bradford County Florida in 1901.There is some confusion in the Compiled Service Records, which identify Hersey as "Kersey." However, I believe the correct name is Hersey. That would be consistent with the pension application and the eye witness account of his death.
You may obtain a copy of the widow's pension application from the Florida State Archives. It is available online in PDF format and you can download the file. The application number is A03176.
William Hersey's final resting place is probably one of the following: (1) He was initially buried by Confederate troops on the battlefield near Rose Farm where he fell; (2) Assuming his grave was found, he was likely reburied elsewhere at Gettysburg; (3) In 1871, some Confederates were removed from Gettysburg and reburied in Laurel Grove Cemetery, Savannah, Ga. Others were removed and reburied in Hollywood Cemetery, Richmond, Virginia. Hersey could have been in one of those groups.
I have recently corresponded with another Hersey relative, Rob Noles. He is also trying to solve the mystery.
Hope this helps a little.
Jim Parrish