 In the late 1960s, Bull established a space program at Norwich University, in Northfield, Vermont.At SRC Bull continued the development of his high-velocity artillery, adapting the HARP smoothbore into a new "reverse rifled" design where the lands of a conventional rifling were replaced by grooves cut into the barrel to make a slightly larger gun also capable of firing existing ammunition.Normally artillery shells are sealed into the rifling by a driving band of soft metal like copper, which demands that the shell be shaped so that it balances at its widest point, where the band is located.