The results of an interlaboratory test program conducted to assess the precision of the Practice Guide for High Strain Rate Testing of Polymers are summarized. Five polymers, PC ABS, TPO, HDPE, 30% short glass fiber-filled PA, and 40% long glass fiber-filled PP, were tested at nominal plastic strain rates of 40/s and 400/s. The test results were used to generate repeatability and reproducibility statistics that were incorporated into a precision statement for the practice guide.