Test Four - Wallboard - Two pieces of ½ inch standard gypsum board are set 3.5 inches apart. The gelatin block is placed 18 inches behind the rear most piece of gypsum. This test event simulates a typical interior building wall. Cartridges : (1) .45ACP Federal Personal Defense 230 grain Hydra-Shok JHP (part # P45HS1) (1) Federal 90 grain Hydra-Shok Personal Defense (Load # PD380HS1H) (1) Hornady 230gr +P XTP (part # 9096) The standard frame/wallboard combination was used as the main barrier, with a half-gallon orange juice carton (waxed cardboard) filled full with water, covered in two layers of 12 ounce denim fabric and placed 18" behind the rearmost face of the two pieces of gypsum board. The Federal Hydra-Shok, fired from a 3.8" barreled semi-auto, impacted at 798 ft/sec and was recovered, unexpanded, at 0.445" diameter. Round completely penetrated the 12" of polyester fiber utilized as the bullet arresting box (placed 4" behind the water jug). Bullet was found sitting on top of the sand of the berm, next to : The .45ACP Hornady XTP bullet was fired from a 5" barrel semi-auto, impacted at 891 ft/sec and was recovered at 0.590" diameter. From the jagged look of the exit hole in the second layer of drywall, it appears that the bullet expanded in the gypsum and impacted the water jug already expanded. Completely perforated the bullet arresting box and was found in a wad of polyester fabric on the face of the berm. Federal .380ACP Personal Defense was fired from a 2.75" barrel semi-auto and impacted at 849 ft/sec. Bullet was recovered at 0.354" average diameter, in a ball of polyester fabric that was about '1 ft/sec' away from leaving the back of the polyester bullet catch box.