Much has been said about the damaging effects of a hollowpoint bullet versus standard FMJ - that which is available wherever 'practice ammunition' is sold. This test was conducted using the same gun for both bullets, both of which were the same weight and impacted at similar velocities. What was different was the design of the nose of the bullet.
Cartridge : 115gr Cor-Bon DPX and Winchester 115gr FMJ
Firearm : 4.0" barrel, recoil-operated semiautomatic
Block calibration : 10.4cm @ 573 ft/sec
Shot 1 - Cor-Bon 115gr DPX. Impacted at 1153 ft/sec. Penetrated to 14.5" (corrected) and expanded to 0.538" average diameter.
Shot 2 - Winchester 'White Box' 115gr FMJ. Impacted at 1172 ft/sec. Penetrated nose-forward to 5.9", at which point the bullet tumbled. This yawing continued on until 13.6", where the bullet apparently righted itself and turned nose forward for the remainder of the travel through the gelatin block (16.0" total travel distance through gelatin). Bullet was recovered undeformed at 0.354" diameter.
Please note that nothing 'evil' happened to the gelatin block, despite being struck with both hollowpoint ammunition and a conventional FMJ, fired from the same gun, at almost the same velocity and hitting the same gelatin block.
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