Non-symmetrical cast ball

[Hubertus]

I got a .40 cal rifle and the .390 mould I'm using for it casts non-symmetrical ball. Measured with the sprue up, on the horizontal one measurement will be .390 but when the ball is turned 90 degrees the measurement will be .396. Will this six thousands difference cause issues to find a proper patch thickness/seal or accuracy issues?

 

[Bassdog1]

Are you just rotating ball right left with sprue still facing up?

 

[Boomerang]

Is it wider at the parting line or 90 degrees from it? Can you see the parting line on the ball between the two halves of the mold after it is cast?
It shouldn't make any difference. Your ball isn't going to be perfectly round by the time it is shot out of the barrel anyway. If it is soft lead, it will conform to patch and barrel when loaded.

 

[Hubertus]

Are you just rotating ball right left with sprue still facing up?

Yes

 

[Hubertus]

Is it wider at the parting line or 90 degrees from it? Can you see the parting line on the ball between the two halves of the mold after it is cast?
It shouldn't make any difference. Your ball isn't going to be perfectly round by the time it is shot out of the barrel anyway. If it is soft lead, it will conform to patch and barrel when loaded.

I’ll check after work tonight where the wider part is in relation to the parting line. To clarify, these aren’t fat from the mould not being tightly closed...there’s no “fin” on the parting line.

 

[Griz44Mag]

By the time you lube, patch, whack with a starter, push with a rod into a bore that is probably .006 (or more) inconsistent in bore, that .006" is pretty much meaningless in a 700 year old reproduced technology.
Shoot it and enjoy.

 

[Erwan]

I would like to say that it's better to have a perfectly symmetrical ball but, when thinking (sometime I do) correctly I see that the thiknes of a Black hair is (sorry I'm talkin' in millimeters) 0.07mm and a blond hair is only 0.04mm, considering the fact that you are going to shoot with greased patches in cotton no rectificated and so with some variations, that after the first shoot the barrel have residues etc, etc. I think your default of only 0,15mm (twoo black hairs twisted together) wont have any influence at the level of the accuracy, conformation and no more for stability when flying...

Perhaps I'm wrong but this is what I'm thinking 'bout what seems a "false problem" (for me)...

Like saids Griz44Mag : "Shoot it and enjoy".

 

[Griz44Mag]

OK, I fell for that one and grabbed grandpas machinist mic,
I am blonde (German) - .0018"
My wife is black headed (Latino) .0026"
My dog is Jack Russel - .0032"

Lesson to be learned? Keep your dog away from your shooting patches.....

 

[hanshi]

Just about every mold I've ever used had at least some slight inconsistency, some a great deal. My Lyman .445" mold will measure from .442" to .445"; but the ball shoots very well. Yes it will be misshapen after it's seated. So IMO it's a non-issue.