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A study was conducted to characterize the effect of density and elemental additions of graphite, copper and nickel on static and dynamic properties of low alloy P/M steels prealloyed with 0.85% molybdenum (ATOMET 4401). Each test parameter was studied at three levels: green density at 7.0, 7.2 and 7.4 g/cm3, graphite at 0.30, 0.45 and 0.60%, copper at 0, 0.5 and 1.0% and nickel at 0, 2.0 and 4.0%. Powder mixes were either single or double pressed to the targeted density, sintered at 1120° C in a nitrogen based atmosphere and tempered in air for one hour at 185° C. Specimens were evaluated for tensile, impact and fatigue strengths. The effect of case hardening was also evaluated on a series of FLN2-4400 and FLN4-4400 specimens pressed to 7.4 g/cm3 and carburized to a depth of 1.25 mm. It was confirmed that density is a key variable to improve impact strength, elongation and fatigue strength. Admixed nickel content also contributed to significantly improve fatigue and tensile strengths.