Depends on location... I go 4cc in the glutes, 2-3 if delts or quads. Did a 5cc ONCE, too much, never again to uncomfortable, it was pharmacy grade human stuff and the oil was THICK.
i've done 4 in the glutes with very little discomfort. you could feel it kinda jiggle for a few days after the shot but it didn';t hurt. i also have hit 3 in teh delts.