Boolit roundness as dropped from the mould?

[Russel Nash]

I casted a bunch of .40 cal -ish boolits from a Lyman mould about 15 years ago.

I never got around to Sizing them.

They had been sitting in a GI ammo can this whole time.

They are about 177 to 178-ish grains:

IMG_8161.jpg

I was going to try my second attempt, ever, at shake and bake powder coating last night.

But, first I thought it might be a good idea to measure about 10 of them for roundness.

Now, I either suck at measuring stuff with digital calipers….or????

Some bullets would measure “north south” at say .403”

Then I would turn them “east west” and the calipers would read say .407”

I could swear there was one that came up as .412”

For grins and giggles last night, I ran about 150 of them through my Lee push through sizer that is 0.401”.

Some went through easy enough.

Some required more gumption.

So I gotta ask….is getting more round boolits strictly up to the mould?

Or can it be strictly operator error?

Or some combination of both?

[Recycled bullet]

I couldn't really tell in your picture, can you please take a zoomed in focused bright photograph showing the bullets?

I'll just say that if you remelt and recast them before you powder coat them it stinks a lot less.

If the mold is not hot enough when you are casting then the molten lead will freeze in an inconsistent pattern usually resulting in random voids, blurry rounded driving bands and edges and ultimately poor fill out.

[justindad]

.403” to .407” can happen. The mold block might not have fully closed. Or, the cavities in the two blocks might not be in alignment. There might be other ways for that to happen too.

[country gent]

In a way it is a function of the blocks in that if the cavities arnt round and aligned to start with then you wont ever get round bullets from it. But dirt a burr or misaligned pins can also have an effect here. Would help inside of east west you gave on the parting line and 90*. This would show misaligned blocks and blocks not closed completely.
Moulds can be lapped to make very round bullets but you cant lap down in size so in you issue 403-407 you would have to lap up to 407/408 .

Depending on the way is off look for small burrs misaligned pins improper seating.

I would size them down to round before powder coating.