I agree with Ill digger. They are all modern. The bottom row are called wad cutters and may be 38 caliber. Top left looks like a 45 caliber and the next two look like muzzle loaders. Accurate measurements of diameter and length will help ID them correctly.
I don't claim to be some kind of expert on bullets but those look kinda modern to me. They remind me of some muzzle loader ammo I've seen before. The second one from the left on the bottom row looks like a handgun round to me. But again, I could be waaaay off.
Have you come across any coinage at this site? To possibly help you date the activity there?
...that lead gets a white patina on it when it has been in the ground a long time.