Bullet diameter out of the mold will vary some depending on the alloy. They may also be slightly out of round. I have always sized my cast bullets using Lyman tools. (4500) You can also get sizers in a number of sizes.
The 44-40 uses bullets at .427, and 44 Spl at .429 in jacketed bullets. So cast would be slightly larger, and given the variation in barrels, you need some choices there in that range.