Jackhammer was first mentioned as a HYDRA leader in Daredevil #121; he first appeared in Daredevil #123 (July 1975) and was created by Tony Isabella and Bob Brown.
The character subsequently appears in Captain America #371 (June 1990), #373-378 (July-October 1990), Guardians of the Galaxy #28-29 (September-October 1992), Captain America #412-414 (February-April 1993), Thunderbolts #24-25 (March-April 1999), and Union Jack #1-2 (November-December 2006).