I recall a long discussion in The Fouling Shot way back when, which eventually classified a bump die as legal for CBA use. Swaging of cast bullets was not an allowed practice, as it pressed the lead into a uniform shape that may or may not have much, if any, resemblance to the original casting. This would violate the original goal of the Association, which was to maximize cast bullet accuracy. Sizing of cast bullets was a long established practice, which, ideally, only uniformed the diameter of the casting to the optimum fit to the bore without changing the overall shape. This was unarguably legal for CBA competition. Bumping the bullet was a bone of contention, since the arrangement not only modified the diameter of the bullet, but also modified the nose shape so it was an exact fit to the leade of the rifle’s bore. Some people objected to this because they said it moved the processing of the cast bullet into the area of swaging, which, IMO it did. However, the change was only in the nose diameter and maybe a slight change in the ogive shape. And this was back in the dark ages when only Hoch (as far as I know) offered lathe-bored mould cavities. Egan was the main man for match grade molds back then, and they were cut with cherries to a standard shape. Nobody had CNC equipment and flash drives full of programs which could be tweaked for tiny changes in configuration, so bumping was allowed, after some controversy. I would doubt that the allowance would go today, with the vast number of offerings from Accurate, NOE, Arsenal, and other manufacturers, and the ability to modify diameters, or even order a custom overall shape. But it sounds to me like the OP just wants a uniform diameter for his castings. One of those Lee sizing setups would be fine for that, or even a properly set-up lubrisizer with the appropriate die and nose punch. My black-powder target bullets all come from custom moulds, and don’t really need sizing as such. The grease-groove castings go through dies that just touch the outside diameter of the “lands” on the bullet, while the grooves are filled with lubricant. A custom sizer die, or even a standard offering that is actually the nominal diameter, would be all that’s needed, I would think.
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