Various .25ACP bullets were tested, including the 45 grain Winchester 45gr Super-X Expanding Point with the shot ball in place and with it removed. In addition, three pure lead hollowpoints were fired, each having a different cavity geometry, to determine the feasability of the production of expanding .25ACP ammunition that penetrates to a minimum of 12.0" in ballistic gelatin. These bullets were handcast using 'dead-soft' lead in a Lyman '2574200' mold, which produced 75gr projectiles of 0.258 ± 0.0005" diameter. These were sized down to 0.250 ± 0.0005" diameter in a sleeved Lee 'lead bullet sizing die' and a portion of the base (~0.100") was cut off using a lathe and a cutoff tool. Firearm : Beretta 21a pistol with 2.4" barrel length. Calibration : 11.7 ± 0.05cm and 618 ± 0.500 ft/sec impact velocity. Shot 1 : 55 grain pure cast lead bullet. Hollowpoint cavity was center-drilled to a depth of 0.165 ± 0.0005" with a 1/8 inch drill bit. Cartridge was loaded with 1.0gr of N310 powder and used CCI small pistol primers, COAL = 0.896 ± 0.0005". Impact velocity was 807 ± 0.500 ft/sec. Average expanded diameter was 0.309 ± 0.0005". Corrected penetration depth was 11.6 ± 0.031". Track outlined on picture of block. Pictured second from left on bullet photo. Shot 2 : was the same as 'shot 1', with the exception of the cavity being drilled to 0.158 ± 0.0005" depth. Bullet impacted at 799 ± 0.500 ft/sec and penetrated to 10.0 ± 0.031" (corrected). Pictured third from left on bullet photo. Shot 3 : was the same as 'shot 1', with the exception of the cavity being drilled to 0.121 ± 0.0005" depth with a 1/16 inch drill bit. Bullet impacted at 803 ± 0.500 ft/sec and exited the block at 11.8 ± 0.031" (corrected) depth. No expansion was observed with this bullet. Pictured fourth from left on bullet photo. Shot 4 : Handloaded Remington 50gr FMJ projectile. 1.2gr of N310 powder and CCI SSP. Bullet impacted at 894 ± 0.500 ft/sec, penetrated 10.7 ± 0.031" (corrected). Recovered diameter was 0.250 ± 0.0005". Shot 5 : Pulled Winchester expanding point bullet, obtained from an interested third party. Shot ball had been removed with pliers, but the cone of the hollowpoint was in apparently usable shape. Bullet diameter of these samples measured 0.241 ± 0.0005". Bullet struck block at an angle ~ 90 degrees offset from the initial axial direction and continued on at this attitude in the block until ~ 75 percent of the bullets penetration. Impact velocity was 967 ± 0.500 ft/sec, penetration was 9.5 ± 0.031" (uncorrected). Shot 6 : Pulled Winchester expanding point bullet, obtained from an interested third party. Shot ball was in place. Bullet diameter of these samples measured 0.241 ± 0.0005". Bullet struck block at an angle ~ 90 degrees offset from the initially axial direction and continued on at this attitude in the block until ~ 80 percent of the bullets penetration. Impact velocity was 967 ± 0.500 ft/sec, penetration was 10.5 ± 0.031" (uncorrected).