Hammad (may Allah have mercy on him) said: I said to Qays bin Sa'd: Get me the document of Muhammad bin Amr bin Hazm. He gave me a document which he said he had taken from Abu Bakr bin Muhammad bin Amr bin Hazm, (stating) that the Prophet (peace and blessings be upon him) wrote it for his grandfather. I read it, and in it was mention of what is to be paid from the obligatory dues of camels. He narrated the hadith until they reach one hundred and twenty: "When they are more than that, count a hiqqah for every fifty, and whatever is left over is returned to the first of the dues of camels. Whatever is fewer than twenty-five, its due is sheep: on every five camels one sheep, not a male, nor an old one, nor a defective one among the sheep."
It is munqati' (broken) between Abu Bakr bin Hazm and the Prophet (peace and blessings be upon him). Qays bin Sa'd took it from a document, not by hearing, and likewise Hammad bin Salamah took it from a document, not by hearing. Although Qays bin Sa'd and Hammad bin Salamah are among the thiqat (trustworthy), this narration of theirs contradicts the narration of the hadith masters from the document of Amr bin Hazm and others. Hammad bin Salamah's memory deteriorated at the end of his life, so the hadith masters do not use as evidence what he narrates in contradiction to others, and they avoid what he alone narrates, especially from Qays bin Sa'd and the like. This hadith combines both matters, besides the break in its chain. And success is from Allah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7268