Grand Slam was born James J. Barney in Chippewa Falls, Wisconsin. His primary military specialty is artillery and secondary is electronics engineer. His first training was done in conventional artillery and he was trained with the 155mm battery. He graduated top of his class from Special Weapons School before being recruited by the G.I. Joe team. He is a qualified expert in several weapons including the M-16, M-1911A1, the H.A.L. (Heavy Artillery Laser) and J.U.M.P. (Jet Mobile Propulsion Unit). He is also capable of estimating distances and trajectories without the use of technology and with great accuracy. Grand Slam is known to be somewhat of a recluse, often preferring to read science fiction and comic books than interact with others.
Grand Slam was created in 1982 for the Hasbro G.I. Joe toy line. His story was then adapted by Larry Hama for the Marvel G.I. Joe: A Real American Hero comic book series.
Grand Slam was one of the initial thirteen members of the G.I. Joe team and appeared in the very first issue. Grand Slam was often seen using the J.U.M.P. jet pack on G.I. Joe missions; a weapon he was highly skilled at using. Despite being one of the original members, Grand Slam is scarcely seen in many issues and quickly moved into a clerical role with the team upon the rebuilding of The Pit Headquarters. He appears in all three incarnations of the G.I. Joe comic series (Marvel, Image/DDP, and IDW). His role as a reinstated Joe proves valuable during the second Cobra Civil War in the DDP G.I. Joe series, but he has little exposure in the IDW G.I. Joe universe as he is killed by a sniper in the same issue (and page for that matter) he is introduced.
Major Story Arcs
Grand Slam appeared in the Sunbow G.I. Joe animated series only for the initial opening mini-series titled A Real American Hero. He was the only original member of the team not to have any other appearances in the series
Grand Slam had a few incarnations in the Hasbro G.I. Joe 3 1/2" figure toy line. He was originally released in 1982 as an original member and was packaged with the H.A.L. (Heavy Artillery Laser). In 1983, Grand Slam again reappeared when Hasbro re-released all original members with the new "swivel arm grip" as opposed to the straight arms they were originally released with. This time he was packaged with his trademark jet pack the J.U.M.P. (Jet Mobile Propulsion Unit). His pads on his arms, legs, and chest were recoloured to silver from their original red, probably due to the close resemblance to another original member Flash, who also shared the same red padded armour. Grand Slam did not appear in the G.I. Joe toy line again until 2007 when he was released in the 8" Sigma 6 team. He also appeared in the 25th anniversary toy line packaged with the S.H.A.R.C. and as a figure for the G.I. Joe: Rise of Cobra live action movie (although he did not appear in the movie).