Alloy problem?

[JedYonkers]

First time poster and long time lurker.
I have a bit of a problem with a batch of lead I have.
I have about 15lbs of the stuff. I started with roughly 7lbs in the pot.
I heated it to about 725* and made sure the mold was hot. I don't think the problem is the mold (lee TL 452-230). Any way the bullets are not filling out very well in the lube grooves and are about 10 grains heavier than the ones I cast on Sunday with a different batch of alloy. 230grains + or - 5 grains. The new mystery mix is dropping them at 240-250 and slightly out of round. I am assuming the out of roundness is due to the poor fill out. I added about 1/2 pound of hard shot hoping to add some antimony and arsenic to harden it up .

What and how much should I add to the mix to harden it up and help fill out?
'Should I add something like Linotype or rotometals super hard and how much would I need ? I'm going for about 10-12 brinell hardness for 45 acp loads.
Am I over looking something? I am most concerned with getting good fillout vs weight.

[375RUGER]

you don't know what you started with, right?

There is a lead alloy calculator sticky in the lead alloy section.

You need to add some tin for fillout. When you added the shot you were just putting in lead and antimony and the trace arsenic.

Antimony and Tin will make a boolit weigh less.

Even though you will be guessing at your alloy the calculator will give you an idea of how much solder or whatever source of tin you choose you should add to a given amount of your mystery metal.

[JedYonkers]

you don't know what you started with, right?

There is a lead alloy calculator sticky in the lead alloy section.

You need to add some tin for fillout. When you added the shot you were just putting in lead and antimony and the trace arsenic.

Antimony and Tin will make a boolit weigh less.

Even though you will be guessing at your alloy the calculator will give you an idea of how much solder or whatever source of tin you choose you should add to a given amount of your mystery metal.

Sorry for the mistake, I thought I'd looked at all the stickies. [smilie=1:

[runfiverun]

they are easy to overlook.
tin will help with your alloy, the second batch being much heavier is caused by there being more lead in the alloy.

[44man]

The TL little bands can over heat too and not fill. They will show a frosty appearance at that spot.

[popper]

If you tumble lube they may be just fine. You have to water drop or oven heat treat to get the arsenic to cause hardening. Convection oven to ~450F for 1 1/2 hr, drop into water quickly. That's 425 +/-5, like the others.