Lee sizing dies go from .358 to .401?

[Cosmic_Charlie]

That would be close enough. I have no trouble shooting boolits a touch smaller than the throats.

[tazman]

So what if your cylinder throats are 3.585 and you only have 3.580 sizing dies from Lee? Open one up slightly or what?

.358 would be a sliding fit in the throats. The boolits will expand slightly(bump up) when the pressure hits the base in any case.
In my experience, Lee sizing dies tend to be about .0005 oversize anyway. That is what my Lee sizing dies leave the boolit after sizing. The others all work out the same way, leaving the boolits .0005 larger than nominal.

[DanLee]

I don't size cast bullets anymore. I let the barrel do it.

[bedbugbilly]

Stopsign32v - taxman explains it well.

What you don't want are cylinder throats that size your boolit down and then expect them to expand to bore size - example - .356 throats and a .358 bore. If your throats are .3585 and your boolit .3585 - that is a good fit - and your bore is .357 - your boolit will easily size down to bore size as it enters the forcing cone.

I shoot Colt and Remington cap and ball revolvers with conversion cylinders - "Navy" revolvers in .36 caliber. I load 38 Colt Long which is shorter tha a 38 spl. ani it is the parent cartridge for the 38 spl. Bore size on a .36 caliber Navy is .375. So . . . . my conversion cylinder throats are .3755. This allows me to use a 125 or 150 grain .375 "heeled" bullet. HOWEVER - I also have the option of using either a .358 hollow base 150 grain Round Nose or a .358 hollow base 148 grain Wad Cutter (I have both molds). SO . . . . that is putting a .358 boolit through a .3655 cylinder throat into a .375 bore. The .358 hollow base soft lead boolits will expand to fit the .375 bore and they give good accuracy. Ed Harris wrote a great article about his tests with .358 hollow base boolits in a revolver with a conversion cylinder that is identical to what one of the revolvers is that I have.

I describe the above to illustrate that you need you throats larger than your bore size and you also need your throats a bit larger than your boolit so the cartridge can chamber easily. A .358 boolit in a .358 throat is almost an interference fit but a .3585 throat should allow the cartridge to drop into each chamber easily without having to apply thumb pressure.

Another example - I have a Uberti Cattleman SAA in 45 Colt. My bore is .452 and my cylinder throats are .455. I have molds that drop at .452 and molds that drop at .454. I very rarely size any of my cast for my revolvers. My cattleman seems to shoot both the .452 and .454 size boolits equally as well and if I do my job, it groups very well at 50 yards.

[Mal Paso]

.358 would be a sliding fit in the throats. The boolits will expand slightly(bump up) when the pressure hits the base in any case.
In my experience, Lee sizing dies tend to be about .005 oversize anyway. That is what my Lee sizing dies leave the boolit after sizing. The others all work out the same way, leaving the boolits .005 larger than nominal.

Do you mean .0005"? Depending in temper and alloy boolits can spring back a half thousandth.

[tazman]

Do you mean .0005"? Depending in temper and alloy boolits can spring back a half thousandth.

You are right. I will correct.