Need advise on casting

[acidviper]

I am very new to casting and i have made several bullets lately but they are all 10grains too heavy. What can i do to lighten up the mix?

[44man]

I am very new to casting and i have made several bullets lately but they are all 10grains too heavy. What can i do to lighten up the mix?
As you get closer to pure lead, boolits will be the heaviest. As you add more tin and antimony, the lighter they get, to a point.
10 gr is well withing normal range of a lot of molds and I never worry about it. Just work loads for accuracy.

[sagacious]

Your post is mighty thin on details and specifics, compadre. I'd reckon you'll get better-- and thus more useful-- info if you give us a little background on your situation and fill in some of the relevant details.

You'll get a lot of guesses and suggestions from folks who are trying to be helpful, but don't know the specifics of your application, but they'll all be just that, guesses.

A mold may not drop bullets equal to the weight specified by the manufacturer, and the exact weight may not matter in your application anyway.

[chris in va]

Are you using wheelweights or pure lead?

[454PB]

Welcome to the forum!

You have to be very lucky to buy a mould that casts the weight on the label. As you already apparently know, the alloy used controls both the weight, and to a certain degree, the diameter.

Depending on the design weight, 10 grains is not a big variation. If it was sold as a 300 gr. boolit, it can weigh anywhere from 280 to 320 grains. However, a .224 mould that was sold as a 55 grain boolit would be unacceptable at 65 grains.

In simple terms, adding antimony will both lighten weight and increase the boolit diameter.

[captain-03]

Will the additional of tin to a straight WW melt increase the diameter of the dropped boolit?

[lwknight]

More tin will do nothing more than help fill-out. It takes about 5 to 6 precent antimony to make larger casts. They will weigh the same but with slightly lower specific gravity. Incalculably small amounts though.
If your tin content exceeds your antimony, you are going backwards.
More than 3% tin is just wasting tin unless you specifically want linotype boolits.
It you increase antimony to say 10 percent then you will need about 4% tin to offset the brittleness.

[lwknight]

As far as boolit weight being heavy, double check your scales and shoot em anyway.