It is the Lyman # 457125 either listed as 500, 520, or 464 grains in the Lyman manuals/ cast bullet handbooks depending on your alloy. Mine come out about 515-520 with straight wheelweights. I also didn't find out until after purchasing the mould that it has a smaller diameter nose than might be ideal for loading in the 458. I need to work with it some more before I completely pass judgement on its suitability in the 458 though. I have had some slightly undersized bullets enter the target completely sideways, while others (of proper size) grouped around an inch and a half. It just seems a little harder to get a consistent cast with this one as compared to other ones I have worked with in the past. I'm considering a Mountain Moulds 440 grain around the first of the year for less recoil and maybe easier casting.
Well, I'm sure this was more than you bargained for, but I think Will Rogers probably had plenty of quotes about the value of "free advice".
captainkirk