The trio that comprised HARD STUFF could boast a good deal of experience in other acts. Frontman John Caan was ex-ATTACK, ATOMIC ROOSTER and ANDROMEDA, drummer Paul Hammond was also an erstwhile ATOMIC ROOSTER man, whilst bassist John Gustafson had previously been with EPISODE SIX, BIG THREE and QUATERMASS. The bassist later performed with GILLAN and guested on Swedish act BALTIK's 1973 eponymous album.

Gustafson, Caan and Hammond had previously forged a short-lived band entitled DAEMON in 1971. Fronted by singer Al Shaw this unit recorded one now extremely scarce album 'The Entrance To Hell' before Shaw exited. The remaining band members stuck together and initially took on the title BULLET releasing one single, the first release for DEEP PURPLE's Purple label. However, threats of a lawsuit from an American band of the same name necessitated a name change to HARD STUFF for the 'Bulletproof' record of 1972. 'Bulletproof' was in fact a re-hash of the DAEMON album, featuring the same songs minus two tracks.

HARD STUFF toured heavily across Europe concentrating on Germany and Italy, very often as support to DEEP PURPLE and also URIAH HEEP. The band's career was abruptly curtailed in a horrific car crash where Hammond and Cann were very badly injured. Although a second album 'Bolex Dementia' surfaced the band were to fold.

Caan aided a reformation of ATOMIC ROOSTER and also deputized on a 1973 THIN LIZZY tour of Germany. Hammond went on to THE SIRENS. Gustafson would re-establish THE BIG THREE in 1973 with guitar player Brian Griffiths and drummer Nigel Olsson for the 'Resurrection' album.

The bassist journeyed through ROXY MUSIC, until September 1975, and the IAN GILLAN BAND, featuring on albums 'Child In Time', 'Clear Air Turbulence' and 'Scarabus'. Gustafson reformed QUATERMASS in 1997.