30:1

[byronw999]

Hey all...

Was going to order some tin till I saw the current prices! I do however have pleny of pure lead and about 25lbs of 60/40 solder...

What proportion od each do I need to make 30:1?

I've done some searches both here and google and cant seem to find what I need.. Most ratios seem to involve WW..

Thanks in advance

Byron

[bpratl]

1 # of 60/40 Solder = 9.6 oz Sn & 6.4 oz Pb
30:1 = 97% PB & 3% Sn
10 #'s (160 oz) of PB + 4.8 oz of SN or (1/2 # of 60/40) should = 10.5 #'s of 30:1

This should be close if I am not mistaken.

[redneckdan]

Cross multiply and divide to the rescue!!!!


anyway.


First the ratios 1/30 for the alloy needed 60/40 for the alloy at hand.

First find the Tin needed from the alloy at hand. for 10lbs of desired alloy you need 5.3 ounces of tin.


10lbs * (1/30) = 5.3 ounces


To get 5.3 ounces of tin from 60/40 you need 8.8 ounces of alloy.

60/40 = 5.3/x x=3.5 ounces cross multiply and divide to find X which equals the amount of lead in the 60/40. add 5.3 + 3.5=8.8 total weight of 60/40 alloy needed to make 10lbs of 30-1 is 8.8 ounces.

To find the amount of lead required subtract 8.8 ounces from 10lbs.

10lbs= 160ounces - 8.8ounces= 151.2 ounces of pure lead


Lets doo the math to double check.

151.2 ounces of pure lead
3.5 ounces of lead in the 60/40
5.3 ounces of tin in the 60/40

1/30 = .03333

5.3/154.7 = .03425


Pretty damn close.

[R.M.]

That matches with Bumpo's alloy calculator.

[byronw999]

Awesome! Thanks... 2 questions

Where would I find this Bumpos alloy calculator and what would be a decent digital scale for measuring the components... All I have now is an old spring loaded kitchen scale.. Not very accurate..

[R.M.]

There's a few versions in this thread. I like the last one.
http://castboolits.gunloads.com/showthread.php?t=105952&highlight=Alloy+Calculator

[bumpo628]

Awesome! Thanks... 2 questions

Where would I find this Bumpos alloy calculator and what would be a decent digital scale for measuring the components... All I have now is an old spring loaded kitchen scale.. Not very accurate..

Here you go:
http://castboolits.gunloads.com/showthread.php?t=105952

The latest release is 3/29/11

[cajun shooter]

While this is very good information and if you are so anal about the exact amounts then by all means , do it. It is no big deal either way if you eyeball each once in a while. After 40 years it will be close enough. Bullet alloy is not so that it has to be the same as mixing the chemicals for the medicine to give to a heart patient. Don't misunderstand my post. If you are in the process of pouring bullets and you add some lead that is not your alloy. You may just drop in some tin that you feel is close to what is called for. you don't have to run and break out the lab scale to be exact. I will not pass up the chance to make a few copies of this sheet as it is nice to have. Thanks for the time and work to provide the info.

[byronw999]

Thanks all! :lovebooli

[Ohio Rusty]

I just cast up some HP boolits (358439's) for my .38 snubby. I made them 35 to 1 (or close enough) .... 2 pounds of pure lead to one ounce of tin.
They cast very nice, bottoms and grroves are perfect. What I did notice was using a softer alloy, the hardened sprue puddle tended to stick in the sprue hole after it was cut from the boolit. With the softer alloy, I didn't need to use a stick to cut the sprues. The sprue plate cut easily with just hand pressure. That will add alot of life to the mould not having to hit on the plate like with a harder alloy to get the sprue off.
When using that much tin .... the boolits came out shinier... or more silvery and bright compared to straight WW lead. They look nice. I'm looking forward to getting some loaded over a good load of unique and see how they expand. They will be self defense rounds for my scandium .357 snubby I recently purchased.
Ohio Rusty ><>