An AP round is designed to penetrate through protctive armour, most AP rounds can even penetrate level 3A protective armour (but may have trouble with gunshields) AP rounds are nicknamed "greenies" by the guys in my PLT because of the dab of green paint on the tip to indicate it's an AP round.
An AP rocket (for example, an AP FFAR) is designed to pentrate the armour of heavy armoured vehicles (tanks) as a sole purpose.
2. Associated Press (Journalism)
4. Armor Piercing
5. Asian Pride..
2. Urban Times (AP) - Kids pass Ebonics test with flying colors.
3. Ruins an infantryman's day
5. No comment