I know it is artillery projectile. Found this in West Virginia digging fence post holes. This was in the Romney WVa area. Lots of fighting took place there during the Civil War. I have been told the little bow tie thing on the bottom was used to tie the powder bag to the projectile. I was also told it was a semi fixed round with the grooves on the side holding the metal bands making it a sabot round. I have had this for many years and know very little about it. Appreciate all input. Thanks.