[458winshooter]

The only thing I can find is a Lyman mannuel using a lead roundnose from mold # 356242 that casts them at 121 grs. or so.Starting load 2.8 grs for 690 fps and 8,600 cup.A max load 4.6 grs. 1001 fps at 16,400 cup this from a 4" test barrel.I see two different listings for this mold,the one in question has two grease grooves.I think it would be a good start.Lyman lists this mould at 120rgs.but their data says 121 using linotype lead.