Cartridge: 85gr Sellier and Bellot FMJ Firearm: CZ-52 with 4.6" barrel length Block calibration: 593 ft/sec and 10.3cm penetration Single shot was fired to the center of the block from a distance of 6 feet. Bullet impacted the block at 1510 ft/sec, penetrated 16.0" of ballistic gelatin, 10" of polyester bullet arresting box (roughly equivalent to 12" of ballistic gelatin), and 1.5" of loose-packed 'play sand'. Bullet penetrated to 7.0" in the gelatin, when it began to tumble. Bullet apparently 'righted itself', traveling base forward from 14.5" onwards. Interestingly, the bullet was recovered from the playsand, in a sideways attitude - indicating that it had once again started to tumble sometime after exit from the ballistic gelatin. Bullet was recovered with no deformation present.