I was wondering if someone could make something like Devenger made, with his ammo resuppliers, but instead of have them look like ammo and have that outline, make it like in HL2, where you can press USE on them and it would supply you with the ammo thats inside it. Type in your console ent_create item_ammo_crate. It comes up with a crate of pistol ammo that indefinitely gives you as much pistol ammo as you want. My thought is, make these SEnts like that, only you should make it like that ammo crate. It would supply you with AR2 ammo on use and the crate would open up, and give you ammo.
By all means, if you must use ADV. Duplicator that would be even better.