I assume you are asking about cast bullets? If a standard diameter jacketed bullet doesn't pass through the throats completely freely, drop through, the throats need to be enlarged by reaming or polishing. If you have slugged the barrel and determined the bore slug will pass through the throats with slight, less than 1 pound, pressure then size your bullets so the pass the throats with about the same pressure or slightly more. No matter what, they should not be so hard to pass the throats that they have to be driven.

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Gunsmithing since 1961