The U.S. Department of Defense recently purchased over three million rounds of 12.7mm (.50 caliber) M903 SLAP (saboted light armor penetrator) ammunition. SLAP is a 7.62mm tungsten penetrator inside a 12.7mm break away, or "sabot", projectile. Thus it is 50 percent faster coming out of the barrel, and able to penetrate 34mm of armor at 500 meters, and 23mm at 1,200 meters. Very useful against light armored vehicles and helicopter gunships (that usually have some armor). Also, a few rounds will tear up any truck's engine (but then so will regular 12.7mm ammo, but SLAP will do a more thorough job of destruction, at longer ranges.) SLAP is considered deadly to light armor out to 1,500 meters. It's 50 percent faster than regular 12.7mm rounds, thus it is more accurate as well.
SLAP is most frequently found on the 12.7mm machine-guns mounted on M-2 infantry vehicles, but any M-2 machine-gun can fire it. SLAP was developed by the U.S. Marine Corps in the 1980s, but is now used by the army as well.