Hard Stuff were an English hard rock group which included John Du Cann and Paul Hammond, formerly of Atomic Rooster. Also in the line-up were vocalist Harry 'Al' Shaw, formerly of Curiosity Shoppe and latterly Export, and John Gustafson, formerly of Quatermass.
Du Cann and Hammond had left Atomic Rooster due to disagreements with Vincent Crane over the increasingly bluesy, soulful direction in which he wanted to take that band. Consequently, compared with Atomic Rooster's more progressive leanings, Hard Stuff were based more heavily on aggressive guitar.
Originally, Du Cann, Hammond and Shaw had formed a band provisionally entitled Daemon, with the intention of eventually touring and recording under the name Atomic Rooster. Gustafson was invited to join them on that basis, but after finding out that Crane retained the rights to the Atomic Rooster name, the quartet decided to continue anyway, but under the name Bullet instead.
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