An assault rifle can fire multi-fire/full auto where as the ones being used to hunt are semi auto only.
Sorry but full auto's are illegal except to those with special license. The assault weopens ban is for semi auto only rifles that share cosmetic features with thier fully auto breathern. The newer sporting rifles look more like assault rifles, and hunting with AR-15's, and simi auto AK 47's is becoming more common.
BTW this is off topic so no more.
http://answers.yahoo.com/question/in...2141357AAmhPKU
http://www.military.com/entertainmen...-round-up.html