[Chad Young]

A number of years back, a company produced a handgun bullet of a hard brass alloy that was designed specifically to defeat soft body armor. This bullet featured a teflon coating to allow the bullet to engage the rifling and spin the bullet. Some media pundits reported that the teflon aided penetration, which is not accurate. The very hard pointed bullet moving very quickly was the primary factor in vest penetration.

To the best of my knowledge, these never entered mass production and are quite illegal to possess. Making a whole bullet from teflon would not be practical as the resulting bullet would not hold up to firing out of a gun very well.