I´ve heard repeated tales of abuse that blacks occasionally faced during their stay as students in Moscow. Particularly those who lived on the campus of the Patrice Lumumba university.
There´s not a tradition in Russia to keep police track of racial abuse or hate speech. Whatever happens of such incidents, is lumped together with general crime statistics.
My impression is that middle class Russians are no more racist than the rest of Eastern Europe. It´s mostly low-income groups that tend to be involved in these incidents. In other words, they are not more abusive or violent toward Africans than they are against each other.
What complicates life for Africans in Russia is our weak tradition of actively opposing racism in daily life. We were too used to letting state take care of it. Besides, a whole lot of us find pride in challenging political correctness, and along with this pride often goes indifference to racial slur, sexism and suchlike.