A firm called RBCD Performance Plus, Inc. recently invented a new 5.56mm bullet using a blended metal process. This produced a bullet that was armor piercing, but had limited penetration on a human body. Thus it would not just pass through people it hit, but would stop and do a lot of damage. The bullet is called APLP. The 60 grain bullet will penetrate metal or other hard objects, but when it hits a warm body, it fragments rapidly. The effect is similar to an explosive round, and turns a non-fatal wound into a kill. SOCOM (Special Operations Command) has so far resisted adopting the round, largely because tests on gelatin did not show the explosive wounding effect. This is because the blended metal does not fragment when it hits cold objects, and the SOCOM tests used the standard gelatin moulds to represent a human body. The gelatin has a temperature of 36 degrees Fahrenheit, while humans and animals are at least 60 degrees warmer. Tests on warm, but dead, animals, show the effect. This was demonstrated in late 2003 when a former SEAL, working for a contractor in Iraq, got into a firefight with Iraqis and hit one in the butt with an APLP round, and killed the Iraqi. The former SEAL had medic training and was able to examine the dead Iraqi and verified the dramatic effect of the APLP round.
The APLP bullet is not recommended for regular troops, because any incident of friendly fire would likely be fatal. But for commandos, it would probably be used exclusively, for these men get into battles where every shot counts. SOCOM allocated money to test the round, but refuses to accept the temperature angle, insisting that the gelatin test shows no fragmentation and that’s that. They are not interested. But those who have used the round on live animals continue to insist that the APLP bullet works as advertised. This would not be the first time the army, or SOCOM, got on the wrong side of an ammunition procurement debate and just dug in their heels in the face of evidence they disagreed with. Some observers suspect that the SOCOM resistance to the APLP round is because SOCOM fears acceptance of the APLP bullets will interfere with SOCOM efforts to get the army to adopt a 6.8mm round for the new M-8 assault rifle.