A method for improving the translation efficiency of fiber strength into composite strength is provided. A single unidirectional tape, single unidirectional fiber web or a stack of unidirectional web/unidirectional tape plies formed from partially oriented fibers/tapes is primed under mild conditions followed by subjecting the primed plies to an axial extension stress in the axial fiber direction of each fiber ply by passage through a compression apparatus. The axial extension stress extends the fibers, strengthening them, while also compacting the plies together and thereby forming a composite having improved strength. Production yield is improved by avoiding maximal fiber stretching and thereby avoiding typical manufacturing loss, and low weight composite armor having increased strength is achieved.