In this study, a standart ferrous powder metallurgy (PM) copper steels were produced as copper ratio gradually was increased between the range of 1-4 % while other PM process parameters were kept constant. Machinability tests were carried out with drilling process on these samples. In machinability tests have been measured thrust forces, tool wears and surface roughness of the hole surface and taken optical photos from generated chips during machining of each materials group. Thus, effect of increasing copper ratio on tool wear and relation with chip formation which results from machining PM materials was experimentally investigated. The results showed that tool wear decreased and chip formation improved with increasing copper ratio. This results are also supported by the data obtained from cutting force and surface roughness