Ray Masters, managing director of Reliance Custodial Services in Avonmouth for eight years up to 2008, was found shot dead at his home in Westbury-sub-Mendip in Somerset.
He was shot point-blank in the chest on the doorstep of his home on Sunday night.
A second man, Michael Harper, 46, was found dead in a nearby churchyard also with shotgun wounds. No other persons are being sought in connection with the case.
It is understood that Harper was the owner of a business which was a sub-contractor for one of Masters’ businesses.
Man shot dead at his home was ex-boss of Bristol security firm (ThisIsBristol.co.uk)