 On 1 June 1863 John F. Reynolds officially became colonel of the 5th; however, he was on detached service as a Major General of Volunteers, commanding a corps of the Army of the Potomac.He was killed a month later on the first day of the Battle of Gettysburg.His replacement as commander of the 5th was another volunteer general, Daniel Butterfield, the composer of the bugle call "Taps".