I have a Lee .475 round ball mold. Anyone here can cut it to .480 ??

[Ohio Rusty]

I have a new unused and long discontinued .475 roundball mold. I'm needing a .480 roundball for my .50 caliber flintlock rifle. Is there anyone on the list that can re-cut the ball from .475 to .480 ?? It is a single ball mould.
Ohio Rusty ><>

[MT Gianni]

Finding thicker patching material would be much easier. I would imagine the cost, if you could find someone, would exceed two lee rb molds.
You might try finding a steel ball bearing the size you want and squeezing it in your mold in a vice.

[longbow]

Lapping it out by 0.005" should be doable but I'm with MT Gianni, I'd try thicker patch material.

If you want to try lapping, I'd do 1/2 at a time in a drill press turning slowly and with little force then put the mould haves together and finish as for normal lapping. That should keep it from going odd shaped I think. Regular moulds tend to oval out when removing more than about 0.003"... in my experience anyway and that is with frequent cleaning and recasting lapping bullets. I suspect an RB mould would cut more at the equator due to surface speed difference between poles and equator. By doing part of the lapping at 90 degrees then finishing with closed mould it should stay round/spherical. I think.

Thicker patch material would be much easier if it gives decent accuracy.

Then there's Jeff Tanner in the UK. He'll cut you any size ball mould you want. His moulds and service are reportedly very good and reasonable prices.

FWIW

Longbow

[OldBearHair]

Ohio Rusty::: You know what I am thinking? How about drilling a small hole in one of your .475 lead balls you have and put a screw in smaller than your sprue hole in the mold. Cut the head off the screw and chuck in drill. Dip in toothpaste and close the mold and spin it some. Clean it out and cast a ball , measure to see what it did. Should that be too slow, maybe try rubbing compound. The next ball that is cast to check the diameter, drill a hole in it and use it for the next spin session and so on.
Also what Longbow said.