Explosive bullets prohibited by customary law; prohibited by St Petersburg declaration 1968 (explosive projectiles under 400g). there are bullets lighter than 400, their purpose is different that's why they are not covered by the convention, because the military advantage is different. It doesn't matter if you are member of the convention, this is customary norm Expanding bullets (dumdum bullets) prohibited by customary law; prohibited on the first Hague conference 1899, bullets which expand easily in the human body and cause unnecessary suffering (Declaration IV,3 concerning expanding bullets). Doesn't matter if you're a member state to the convention or not. Prohibited are two types of means of these bullets, but technical engineers have developed different means to get the same effect;