After Magnum split, a spin off group featuring Catley and Clarkin was formed called Hard Rain, and they released the albums Hard Rain and When The Good Times Come. It was around this time that Catley launched a solo career using various songwriters, including Gary Hughes of the band Ten. However, Hard Rain found gigs and bookings hard to come by, and there were discussions about renaming the band as Magnum. Also, at this time, Catley was becoming increasingly focused on his solo career, and he quit Hard Rain, marking the end of a working relationship with Clarkin that dated back to 1972. After a quiet period Clarkin announced the end of Hard Rain.

Source: http://www.metalstorm.net/bands/biography.php?band_id=2344&bandname=Magnum