We describe an experiment that tests the hypothesis that projectile points with high thickness: length ratios are more durable than points with low thickness: length ratios. Fifty obsidian projectile points were manufactured to specific lengths, widths, and thicknesses. These were then fired into a deer carcass with a bow repeatedly until each point broke. None of the points were resharpened. The hardness of the material struck was a significant predictor of a point's durability. Controlling for this variable, however, we found that points with a high thickness: length ratio (>.121) were slightly albeit significantly more durable than those with a low ratio. No other attribute of size or shape was a significant predictor of durability.