Cartridge : Various .38 Specials Firearm : .357 Magnum revolver with 4.0" barrel length Block calibration : All depths are corrected depths Shot 1 : Remington 158gr +P LHP ("FBI load" Part #R38S12) impacted at 932 ft/sec and penetrated to 15.6". Bullet was recovered at 0.636". If you look at the picture of the bullets (far right bullet), you may notice that the metal that constitutes the expanded portion of the bullet has broken off. This apparently occured as I pulled the bullet out of the bullet catch box, as the lead traveled with the bullet several inches into this box, after leaving the back of the gelatin block in one piece. Shot 2 : Federal Gold Medal Match 148gr wadcutter, impacted at 721 ft/sec and expanded to 0.422" average diameter. Penetrated to 16.0"+. Penetration depth given for shots 1&2 are estimated because the physical block used in the test was 16.0" deep and these bullets penetrated through this block and then far into the polyester bullet arresting box. So, in both cases, expect the penetration to be in the neighborhood of 'plenty'. Figure 10-10 in Bullet Penetration was used, with an 'X' value of 18" and calibration depth of 11.25cm for shot 1 and 10.70cm for shot 2. Shot 3 : Federal 129gr +P Hydra-Shok JHP, impacted at 985 ft/sec, penetrated to 12.0". Average diameter was 0.729". Shot 4 : Winchester 130gr +P SXT JHP, impacted at 923 ft/sec, penetrated to 9.75". Average diameter was 0.617". Shot 5 : Speer 125gr +P Gold Dot, impacted at 888 ft/sec, penetrated to 12.6". Average diameter was 0.503". Talk with other shooters about this test on The High Road.org : www.thehighroad.org