The bullet appears to be a fired .45-70 Springfield "Government" rifle bullet.
If the flat bottom of its body-grooves has multiple tiny parallel ridges, it is from the 1880s to the early 20th-Century. The photo below shows the tiny parallel ridges I'm talking about. That is known as a "reeded" body-groove.
If the grooves are smooth-bottomed (no ridges), it is from sometime between 1873 and approximately 1880.
Precise measurement of your bullet's diameter (in hundredths-of-an-inch) is needed for verification of its ID. If you don't have a Digital Caliper for that kind of measuring, here's something else you can try. If it is a .45-70 bullet, it will be a teeny bit larger than 7/16-inch wide across its flat base.
The ball seems to be some other metal than lead, and if so it is not a bullet. First, test it with a magnet to see if it is iron. If not, make a tiny scrape on it and tell us what color the metal is. (Yellow, orange/golden, pink/red, or silvery?)