Do molds generally drop larger than listed? And other noob questions...

[MAGA]

Hello, I have handloaded for years but casting is a whole new animal to me, I have the Lyman handbook and have done lots of reading....

I am at the looking for molds stage now and have a few questions. I know ideally I need to slug my barrels and I will if I have problems but I have several of the same caliber I would like to feed the same bullet.

For 9mm I used to purchase coated bullets sized to .356 from ACME and they shot well
I am looking for a 147gr mold (hopefully I can get one from Miha) and almost all are .356
Do molds usually drop bullets slightly over the listed diameter?
I have done quite a bit of reading and it seems most of you guys recommend to size to .357 and not .356?
So if I buy a .356 mold and the bullets drop .356 I cant size them up to .357 using a lee push thru correct?
I will be HI-TEKcoating these also so I plan on sizing after coating.

[KMac]

I believe the HI-TEK Coating will add .001 to .0015 size to the boolits. So if they drop at .356 the coating should make them .357 to .3575.
You will have to pour some boolits and measure them to make sure what size they will drop. Different alloys will drop at different size.

[Larry Gibson]

The diameter of the bullets from any mould is dependent on what diameter the mould was cut for WITH WHAT ALLOY . Most commercial moulds have a +/- tolerance and will drop bullets .001 - .003 over allowing for sizing the specified nominal diameter. Custom moulds of quality will drop at the specified diameter with the specified alloy. Variations in the temperature of the alloy, the mould along with the casting technique can also cause variations in diameter.

[243winxb]

The higher % of antimony in the alloy, the larger the diameter.

[runfiverun]

IME.
newer lymans probably won't.
rcbs usually will make advertised and maybe .001 more.
saeco usually makes advertised diameter.
noe is generally .002 over.
accurate will make what you ask for with your alloy.
LEE..yeah,, well. usually, sometimes bigger, sometimes not.

[OS OK]

200863

This should give you some idea of size differences you can expect from different alloys...

[runfiverun]

a copy of that chart is tacked on the wall behind my casting pot.
it doesn't help me too much if I ain't got no number-2 or lino-type alloy though.

[OS OK]

a copy of that chart is tacked on the wall behind my casting pot.
it doesn't help me too much if I ain't got no number-2 or lino-type alloy though.

We can fix that problem with one word . . .

R O T O M E T A L S

[JonB_in_Glencoe]

SNIP...

For 9mm I used to purchase coated bullets sized to .356 from ACME and they shot well
I am looking for a 147gr mold (hopefully I can get one from Miha) and almost all are .356
Do molds usually drop bullets slightly over the listed diameter?

MAGA,
welcome to the forum.

From my experience (owning about half-a-dozen brass molds made by MP Molds), they drop right on, or .001 larger using straight COWW alloy.