Alloys change in dia

[semtav]

If I change from 30 -1 to 20 -1 (lead -tin), can I expect larger dia bullets?
thanks
Brian

[captaint]

Brian, I think so. Don't have enough experience to say how much. Maybe half a thou or so. Some antimony might make more difference, if you're not shooting BP. Give it shot... enjoy Mike

[RobS]

semtav:

Yes, but it will be very, very slight difference. Here is a good read for you and will help you out with your question:

http://www.lasc.us/CastBulletNotes.htm

[44man]

Not enough to even try and measure. You need antimony.

[semtav]

Reason I asked, I'm shooting BP with bullets cast from 20-1 and 30-1.
I'm wanting to get a custom mold that drops a minimum of .410 to .4105 with those two alloys, and the mold maker I will be using uses 30-1 for his test dia.
I just wanted to make sure if I specify .410 dia. , when I switch to 20-1, I will get larger, not smaller bullets.

thanks
Brian

[RobS]

You'll be good to go, however a mold which cast a bit larger is better than one that spits out boolits a bit small as you can always size down a larger boolit.

[lwknight]

I think that NASA might have some equipment that can detect the difference between the 2 alloys shrinkage. Most of us do not.