This study investigates the fabrication and characterization of coppergraphite (CuGr) composites with varying graphite content (10, 20, and 30 wt.%) for potential applications in electrical contacts, such as pantograph sliders for high-speed trains. The composites were prepared using mechanical ball milling of high-purity copper and graphite powders, followed by cold pressing at 2 tons and sintering at 900 °C in a coal-based reducing atmosphere to prevent oxidation. X-ray diffraction (XRD) analysis confirmed the presence of copper (Cu), graphite (C), and minor copper oxide (Cu₂O) phases, with graphite peak intensity increasing proportionally with its content. Brinell hardness tests revealed a significant decrease in hardness with higher graphite concentrations due to graphite's inherent softness. However, extended heat treatment (4–10 hours) of the CuGr30 composite demonstrated a non-linear hardness trend: initial reduction (38.9 HB to 27.9 HB at 6 hours) due to graphite agglomeration, followed by recovery (40.1 HB at 10 hours) attributed to improved interfacial bonding and microstructural homogenization. Microstructural analysis supported these findings, showing enhanced graphite dispersion and stronger Cu-C interaction with prolonged sintering. The results highlight the critical role of graphite content and heat treatment duration in optimizing the mechanical properties of CuGr composites.