Muir took the lead with a well-worked try by Jordan Edmunds. Chris Laidlaw converted. They added a second through Dougie Steele, Laidlaw adding the extras.
Their third try came just before the break, Iain Moody’s great break from the base of the scrum setting up Otulea Katoa for the score which Steele converted.
Edmunds added his second before Paddy Kelly pulled one back for Hawks. Dale Robertson got Muir’s fifth try before Andy Hill’s late Hawks consolation.