Found then lost an old bullet, what date could you catogorize it?

[makahaman]

Was water hunting and was finding tons of lead objects then saw an old lead bullet, I was going to pick it up but lost it!! It looked like the ones guys find in the civil war battle fields. The two or three ringed one, I am not sure what its called but what would you date that bullet? And what is it called? I am no expert in relics so could someone give me an idea as to the age of this bullet? I will try to post a picture from the web...