Shelhamer rode Sun Egret to a fifth place finish in the 1938 Preakness Stakes won by Dauber.
In 1940 he rode Level Best, American Champion Two-Year-Old Filly, to a 5 length victory in the Old Colony Stakes at Narragansett Park.
In 1942 he was aboard Sweep Swinger and finished tenth in the Kentucky Derby won by Shut Out.
He was under contract to Hall of Fame trainer H. Guy Bedwell and rode most of his races on the Maryland circuit until his retirement in 1945.
He was one of three stewards at the very first Breeder's Cup at Hollywood Park Racetrack in 1984 that saw the winner Wild Again remain in first position after a roughly run stretch drive.