To size or not to size, that is the question.

[GuyKickinit]

I am new to casting, and as the weather warms I will be doing some for cowboy loads. Do you have to size them whether or not they have wax lube or powder coat?. I cast a bunch of .358 with the Lee 6 cavity and they come out around .3585 up to .360.
I have read that not all bullets need to be sized due to the cnc work on the moulds. I occasionally have seen the mould marks, so that user error. Or, should I size them all for consistency?

[Winger Ed.]

You'll see differences in diameter from various alloys no matter how perfect the mold is.
Using normal precautions-- Try a few and see how they work.

But for consistent accuracy, most folks would encourage you to size them.

[Dieselhorses]

As Winger mentioned-"consistency". Also I used to size and shoot before I "slugged" my bores. Slugging will determine what consistent "size" you need.

[fredj338]

I size everything because I want things to be more uniform. Especially important with mixed brass. You get a thick case wall & a 0.360" bullet, you may have a chambering issue.

[bmortell]

as lee says if they chamber you can shoot em unsized.

[HangFireW8]

I lube in the lubrisizer, sometimes no sizing occurs because I use a large enough sizer. But, occasionally I will catch an oddball that was cast with the mold handles open, and feel the sizing resistance.

Those of you who are perfect won't have this problem.

[mdi]

A few things are necessary to answer the question. For trouble free use of cast bullets you need to know your gun. A 38/357 is supposed to be .357" groove diameter, but do you know for sure?. Do you know the real groove diameter of your gun? If a oversize bullet passes through a smaller cylinder throat, it will be sized down. Do you know the dimensions of your cylinder throats? Normally cast bullets are .001"-.003" larger than groove diameter. Are your cylinder throats larger than the grove diameter? Know your gun and use bullets that fit your gun, or just...

[Bookworm]

I have somewhat changed my thinking on this question.

I've been reloading since the late 1980s, including purchased cast lead. I've been casting just a few years..

When I started casting, I used many Lee tumble-lube designs (still do), and never sized. Now, I size almost all boolits, including the Lee tumble-lube.

What I have discovered, is that the push-through sizers are very, very fast. I generally tumble-lube 2 coats, and it's nothing to run the boolits through a NOE Sizer in between lube coats. I can size several hundred boolits in a very short time. A dozen or more a minute is easy to do.

My answer ? If you are casting tumble-lube designs, shoot em as is for now, and as you progress in the hobby, and accumulate more equipment, you may decide to start sizing.

[Stephen Cohen]

I size all cast for uniformity, I trim all cases and de bure inside and out of primer pockets for same reason. I get uniform crimps and the accuracy shows it is all worth it. Cowboy matches are won by speed accuracy and smooth function of your firearms, get one jam or failure in the lever section because of oversize cast or bad crimp and your day is done. Regards Stephen

[44Blam]

Sizing is a quick and easy step. Just get the Lee passthrough die for your diameter. They will make it if it's not listed. It takes very little time and will help with consistency.

[JonB_in_Glencoe]

SNIP...

Or, should I size them all for consistency?
Yep, size 'em all

[GuyKickinit]

These are for 38/357 Cimarron Pistolero's and a Rossi 92 same cal. (slicked). I have been loading cast from the Missouri Bullet co. when I find a used bullet it shows the lan marks but not too deep. I measured the cast ones from them and they are pretty consistent at .358-.359

My mould is .358 and has the lube groove. I got some powder coat but am rethinking about tumble lube. Definitely looking at the lee sizing kit. It's cheap enough.

[stubshaft]

Size them!

[fredj338]

I remember reading Recluse’s first post on making 45-45-10: “I always size every bullet. Always. Every one.”

I think that’s a pretty good maxim, although I will blow off sizing in some cases, particularly when I have a nice uniform mould that drops everything within .001” or so.


Sent from my iPhone using Tapatalk

I have been casting for 40y, never had that happen. The mold may be perfect but my alloy & casting temps will vary, sometimes quite a bit.

[GuyKickinit]

How about tumble lubing bullets with a lube groove. I've also read, that a bullet should be sized before and after tumble lube or PC. Doesn't make sense to me. Is the TL actually that thick? Is the PC that thick? I'd rather not start off with a zillion steps.
I think size then lube.

[RED BEAR]

I size all but only because thats how i lube them . If you lube another way or powder coat and they are of an acceptable size then i say go for it and see how it works in your gun. What works for me may not work for you. Only trying will tell.

[JonB_in_Glencoe]

How about tumble lubing bullets with a lube groove. I've also read, that a bullet should be sized before and after tumble lube or PC. Doesn't make sense to me. Is the TL actually that thick? Is the PC that thick? I'd rather not start off with a zillion steps.
I think size then lube.
Yep, I TL boolits with Lube groove.
Yep I TL, then size, then TL again...this is real common, let me explain.

I use 45-45-10 and put on a coat so thin, it's difficult to see, putting it on that thin makes it possible to miss a spot, also the TL lubes the size die, making sizing real easy, but sizing usually removes the lube from the area that will contact the bore. So putting on a second thin coat of lube fixes that area, as well as covering any area missed from the first thin coat.

Tumble lubing and sizing in push through dies goes very fast, so it doesn't matter if we are seemingly adding steps.

[GuyKickinit]

So basically, sizing all just ensures conformity. I need to measure my barrels. The Cylinder mouth is closest to the forcing cone, yes? Do I also measure the cone or just past it? Measuring the barrel; do I measure the smallest circumference, or with in the grooves.
Mind you I'm not a total doofus, but close. I just want to make sure I do it right.

[JonB_in_Glencoe]

I'll let the others who suggested measuring give you directions on measuring.

Myself? I'd just size the boolits at .359 and load 'em up.
If there are cycling/shooting problems, then break out the measuring tools.

[mdi]

Some will tell you about "drop through", "push through", etc., but I want facts. The cylinder throat is the "muzzle end" of the cylinder. You can slug it the same way as slugging the barrel; drive a lead slug through the cylinder from back to front and measure with a micrometer. This whole idea is about fitting your lead bullet to your gun.

Visualize a bullet leaving the case. The bullet travels a short distance to the throat, and if it is larger than the throat, it gets sized down to the diameter of the throat. Then the bullet enters the forcing cone and is centered and swaged down to a tight fit in the barrel, sealing gasses and preventing barrel leading.The bullet is still larger than the groove diameter and it enters the rifling and grips the rifling while continuing to seal the barrel. If a bullet does not seal the barrel for any reason (too hard, too small) then accuracy declines and lead fouling is deposited on the barrel ID.

That's the way I was informed/taught many years ago and fitting cast bullets to the gun had given me some very accurate, trouble free, clean shooting boolits...

[David2011]

I occasionally have seen the mould marks, so that user error. Or, should I size them all for consistency?

If you’re seeing mold marks in your boolits that’s as good as it gets. You’re getting pretty much perfect flow in the mold. Every boolit I cast gets sized. PC boolits are sized only after I coat them.