Al-Sha'bi (may Allah have mercy on him) said: Abdullah (may Allah be pleased with him) would not make mawlas heirs alongside blood relatives, and Ali and Zayd (may Allah be pleased with them both) both used to say: When the blood relatives are sharers, they get their share and the rest is for the mawlas; they are kalalah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الفرائض / 12389