I have three, one of which has the "W.C." mark and the other two are unmarked. One of the unmarked ones is the nice condition sabot on the bottom of the exact 30pdr rebated Brooke shown in Bell's book. I know it and the other unmarked one (off a shell) were recovered near Fort McGilvery at Petersburg. I think the marked one which is on a smooth sided 30pdr is from there too, but not positive until I do a little research.