A method of forming a fiber-reinforced molding compound. The method includes establishing a melt stream of a source material including a first polymeric material having a first melt temperature in an extruder and dosing a composite material into the melt stream. The composite material includes pre-impregnated reinforcing fibers comprising reinforcing filaments and a second polymeric material having a second melt temperature greater than the first melt temperature. The composite material has at least 30% of the reinforcing filaments protected by the polymeric material such that the polymeric material surrounds each filament completely forming a barrier between it and an adjacent filament in the at least 30% of the filaments. The temperature of the melt stream at dosing is below the second melt temperature. The method includes forming a molding compound from the source and composite materials. The method includes dispensing the molding compound to produce a part.