mold sizer question

[45fan]

First off hello all, recently became a member and have been looking around the forum just soaking up all sorts of great info. I am about to buy my molds for hand gun rounds, i shoot mainly 45acp and 38 special.

My question is the 38 mold I am looking at is made by Lee with a diameter of .358, I do shoot 9mm as well (though very few rounds in comparison) the diameter for 9mm molds are .356 (again Lee molds) is it possible to save a little money buy using the boolits I will cast with the 38 mold and run them through the 9mm .356 sizer die. Saving the cost of another mold. Or would this eliminate the lube grooves and therefore this isnt an option?

If this question has been asked before and i just missed it I appologize. This forum I have seen already has lots of experience and will steer me in the right direction. Thanks in advance for the help all. Happy shooting!

[Danderdude]

It won't eliminate them, but they will be shallower for sure.

To reduce the pressure on the press/lubesizer I would personally run them through the .358 first, and then the .356. If the mold drops at .361 or something (which is not uncommon) the jump to .356 in one stroke is enough to put the bullet ever so slightly out-of-balance, sizing one side more than the other.

Those extra few thousandths make a difference.

[462]

Chances are that a Lee .358" mould will drop closer to .360" than .358". Additionally, their conventional lube grooves are quite shallow. If you are going the tumble-lube route, the grooves are more shallow, still.

Have you slugged the cylinder throats and barrels? They will determine the sizing die you will need. Generally, a boolit .001" fatter than the largest cylinder throat (revolver) or barrel (auto-loader) is best. So, if cylinder throats measure .357", you would want a .358" boolit. If the 9 mm barrel measures .356", you would want a .357" boolit. Taking a dropped .360" boolit down to .357" may or may not work, due to the deduction of the lube groove capacity.

Bottom line 1: There are so many varibles, when it comes to cast boolits, that there is almost always no pat answer. So, try one mould.
Bottom line 2: Lee moulds are inexpensive, buy one of each and eliminate at least one variable.

[2muchstuf]

FWIW
I cast a 125 gr. from a 358-242 sized to .358.
I shoot it out of my .38s and .357 and my son uses it in his 9mm.
It works for him. doesn't mean it will work for you though.
Just food for thought.
Hope this helps.
2

[45fan]

Have you slugged the cylinder throats and barrels? They will determine the sizing die you will need. Generally, a boolit .001" fatter than the largest cylinder throat (revolver) or barrel (auto-loader) is best. So, if cylinder throats measure .357", you would want a .358" boolit. If the 9 mm barrel measures .356", you would want a .357" boolit. Taking a dropped .360" boolit down to .357" may or may not work, due to the deduction of the lube groove capacity.

462 what exactly is slugging? how do i do it?

[2muchstuf]

To slug your barrel or cylinder throat pound a WELL OILED soft lead slug down a WELL OILED barrel.
Measure what comes out.
That's all there is to it.
As said before , your looking for slightly bigger than your measurement.
2

[462]

Use a brass rod (not a wooden dowel) and a mallet (non-metal) to tap the slug through the barrel and cylinder throats. Measure with a micrometer, not a caliper.