That is odd. Why would he write a will at all if he didn't want to specify who his property went to when he died? What does the will say if it doesn't say that?
If he did have property and its not mentioned in the Will, then intestacy laws apply. They kick in where there is no will at all, and this would be treated like that. His assets go to his next of kin. If he was married with kids, 1/3 goes to his spouse & 2/3 to his children. If there are no kids, it all goes to the surviving spouse. If there is no spouse but there are kids, it will be divided equally between them. If he was single/childless, parents would be considered his next of kin, then his siblings.