Finally made it out to my family's property which has two old houses on it. Found this when I crawled under the porch of the oldest house. It has 3 rings but is solid at the bottom.
Shaped like a colt pistol bullet, need measurements to be sure. Note in the picture of the open bullet mold, there is a round ball, and a bullet shaped like your find. This mold is for the .44 caliber 1861 Colt Navy cap and ball revolver.
