Some years ago (1992-ish) I acquired a large assortment of aluminum 25mm sabot pieces that came from a firing range at the USMC base Camp Pendleton. There were 4 or five distinct variations of sabot types. Some were two-piece, some were four-piece and the larger portion were three-piece. The most interesting thing was that each piece was hand engraved with a number and letter. For example, a three piece sabot would be numbered 203-A, 203-B and 203-C. Obviously these were experimentals, but why were they fired at Camp Pendleton? Why were the sabot pieces not recovered if they were numbered, apparently to identify location after firing? Any information on this program would be appreciated. The best examples and complete matched sets now reside at the Woodin Laboratory just in case anyone was curious.