Well the pards over on the Colt forum dont have any answers either, including a coupl a fine fellers who reportedly own original Walkers with ironclad provenance per the 2003 TGCA Parade of Walkers. The Pedersoli mold makes a lightweight 170 grain pickett conical. I am going to play around with a pure lead teardrop sinker that has a similar profile put on a lathe and whittle it down to close to the original spec weight of 218 grains, fill up the swivel hole with molten lead then , use thus as a master for a plaster if paris mold. Once I test these out, I may modify a Pedersoli mold to make a heavier more historically accurate weight conical.