I was looking through a case of relics that I haven't seen in a while and noticed this unique 3-ringer. Help me ID this one guys. It's side cast, longer & heavier than a standard Minie, and has some sort of teet in the cavity with a hole in it. Not sure if it's a a Georgia teet, explosive, or just a casting mark. Also has a sprue on the nose. Of almost 1000 bullets in my collection, I don't have any others quite like it. Thanks in advance for the help.