The unelected bureaucrats at BATFE have no legitimate power to ban ammunition. Arguing fine points about one type of ammunition or another misses the constitutional reality of the subject. They fall into the subterfuge trap set by the Obama administration’s headlong disdain for the U.S. Constitution and the rule of law.
Banning ammunition infringes upon the Second Amendment and is forbidden.
Call or write your congress critters.
It is up to "We the People" to put a stop to this abuse of power. If they ban this ammo, what will be next? With few exceptions, all rifle ammo will penetrate the standard police issue body armor. If they start here, how long before they ban some other ammo they consider armor piercing.