FOUND NEAR NASHVILLE OHIO. FIRST FINDS OF THE YEAR. I HAVE BEEN OUT ALMOST EVERY WEEKEND SINCE JANUARY AND THESE ARE THE FIRST PIECES IVE BEEN ABLE TO ACTUALLY RECOGNIZE AS NOT JUST RUSTED UP JUNK. I HAVE NO IDEA ON THE DATE TO THE BULLET, SHOTGUN PRIMER LOOKS LIKE 1930'S MAYBE.
Your bullet, is a rifled shotgun slug. You can tell because of the twist marks on it. These were meant to help stabilize the slug as it left the barrel of the shotgun. Most of the time they are used by deer hunters. It's not super old. Most companies started making those in the 1980's.