Morphological typologies of projectile points in North America have often been employed as time-sensitive prehistoric cultural markers. This article demonstrates that the contingencies of point manufacture, hafting, use, and rejuvenation create morphological changes that may render questionable use of these morphological typologies as prehistoric cultural markers. Some 30 projectile points were replicated according to the attributes of a commonly employed typological scheme for the Great Basin. Experiments with hafting, impact, and rejuvenation demonstrate that a single point-type may manifest more than one time-sensitive shape within its normal use-life.