Percentages of tin...


Well-Known Member
Having difficulties wrapping my brain around 5 & 10% Tin alloys.

16oz of pure pb + ? Tin = 5% tin mixed alloy?

Same question only 10%....

Shouldn’t be that difficult but I keep getting different answers in my head and calculations.

I want a 5% tin mix in my alloy.

To do it one needs know amounts of each item. So how much tin in 16oz of lead would equal 5% tin composition?

Thanks guys

Last edited:


Well-Known Member
here I will help confuse you even further.
if your trying to make 20 to 1 it doesn't come out to 20 lbs, it comes out to 21 lbs.
20 lbs of lead and 1 lb of tin is the proper ratio.
this of course skews the actual number away from 5%. [off the top of my head it comes out to like 4.89%]
to make a smaller batch you want 5 lbs. of lead and 4oz. of tin, or 2.5lbs. of lead and 2 oz of tin, or 1.25lbs of lead and 1oz. of tin.


High Steppes of Eastern Washington
There are three common systems for lead alloys: 1/20 is one pound of tin mixed with 19 pounds of lead (twenty pounds of alloy), 20 to 1 is twenty pounds of lead mixed with one pound of tin (twenty one pounds of alloy); 5% of the total alloy is tin 95% lead (one pound of tin mixed with nineteen pounds of lead for twenty pounds of alloy).


Well-Known Member
1/10, 10% whatever - does it really make that much difference? i.e. 9 1/2 - 10 1/2%? Point is your not balancing your checkbook so ? Bumpo's alloy calculator and a decent scale will do fine.


Well-Known Member
the bank balances my checkbook it's their job.

4.9-5.0 meh nobody never gonna know the difference unless they are a lawyer with a buddy at a spectral analysis plant that has nothing better to do that day.