Found this guy today. Hollow back. No writing Guessing late 1800s. Mike Holt

Had a good day at an old and new permission in Saratoga. Found my first reale! Also 2 round balls that I believe are canister shot. They ring up 12/13 on Equinox. Smaller musket balls usually ring up 16-18. Also found a small button with a crown and gilt in middle. Still researching but anyone familiar with this button? Mike Holt