Board Thread:Questions and Answers/@comment-1620907-20151127200839/@comment-24909831-20170811170254

As you said yourself, Primaris chapters are not descendants of the First Founding chapters but of the Primarchs themselves (8thE Rulebook; pg 59).

So there are no Space Wolves' successors beside the ill-fated Wolf Brothers from the Second Founding. Primaris chapters are essentially a new First Founding, and not 27th Founding. Actually I think it is never even written as "27th Founding", but always as "Ultima Founding".

I wholeheartedly support the idea of sons of Russ chapters. But they are not Space Wolves' successors, because the Primaris marines' gene-seed is not same stuff which is in the "traditional" Space Marines.