 Chernopeev worked as sergeant in Bulgarian Army from 1889 to 1899.Afterwards he became an active member of the Macedonian liberation movement and took part in the Miss Stone Affair in 1901 in Pirin Mountain.After the suppression of the Ilinden-Preobrazhenie Uprising in 1903 together with Yane Sandanski and Dimo Hadjidimov he set the base of the left wing of IMRO.