The use of Mn in PM steels has been recently reconsidered because of the possibility of alloying through the gaseous phase. In the present work the reliability of Fe-Mn-C sintered steels is evaluated in dependence on powder grade and manganese carrier type employed for sintered steel production. Three types of iron powders were used for confection of sintered samples: two of them were sponge iron powders, the third was a water atomised one. Manganese was added in the from of high- and low carbon ferromanganese and as electrolytic manganese to achieve 5 wt.% Mn. Vickers hardness measurements were used to calculate the homogeneity moduli h. Significant differences in dependence of powder and manganese carrier type were found. The use of water atomised powder resulted in low reliability, the best performance showed the sponge iron NC 100.24. Best results were obtained using high-carbon ferromanganese and electrolytic manganese, the worst with low-carbon ferromanganese.