As a matter of fact, Pete and I have been discussing the likelihood that some Virginia Reads had pre-cast iron bases for several years now. It seemed pretty clear they did, but we lacked any convincing proof. About one month ago, he deactivated a beautiful 3 inch Read shell for me (see first item below) and we both agreed that the base appeared to be pre-cast, like that shrapnel from the Vicksburg area you recently purchased. I saw it about a week ago on the dealer's web site and downloaded those same three views. The sabot appears to be die-struck and fitted with an iron base knob insert. Remember, Vicksburg received around 1,000 Reads from Virginia in late 1862. We know that some VA foundries put rectangular cuts around the center hole. I'm guessing that interesting artifact came from one of those VA Reads. Items #2,3 &4 below are examples of other 3 inch Reads that appear to have pre-cast base knobs. All are on shells cast horizontally - with mold seams running the length of the body - like the earlier Mullanes and Archers. All appear to date from late 1862. By mid-1863, nearly all VA Reads were nose-cast vertically with the base knob formed at the end of the primary pour. Melting of the imbedded portion was recognized as a problem. We are still learning about this process and it is under active consideration. Mike, your relic base provides an important piece to the puzzle. If you are not in 'love' with it, sell it to me for a profit at some future time and I'll donate it to Pete George's excellent study collection of bases.
Woodenhead