Sayyiduna Ibn Abbas (may Allah be pleased with them both) says: A man asked the Prophet (peace and blessings be upon him): I shaved my head before sacrificing. He (peace and blessings be upon him) said: "There is no harm." Another said: I did the stoning after evening had come. He (peace and blessings be upon him) said: "There is no harm." So that day, whatever he (peace and blessings be upon him) was asked about, he (peace and blessings be upon him) said the same: "There is no harm." And he did not order any expiation.
This chain is sahih (authentic).
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 9626