COWW+2% Tin formula ?

Walks

Well-Known Member
I've read in several Websites that a lot use an alloy of COWW plus 2% Tin added for most medium loads.
I wanna make sure I have formula down.
20lbs COWW, divided by 16 ounces equals 320
Ounces. Which is then divided by 2%.
That equals 6.4 ounces of Tin.

Is that formula right ?

Thanks Guys
 

Rick

Moderator
Staff member
I weigh the ingots going into the pot on a digital postal scale in ounces, then use a calculator to determine how many ounces of Sn at 2%. Can't get any more simple or easier than that.
 

Rick

Moderator
Staff member
Ok, long form. Weigh ingots, scale says 6 pounds 4 ounces. Multiply 6 (pounds) times 16 (ounces in a pound), that comes to 96 ounces. Now add in the additional 4 four ounces and you have 100 ounces of alloy. Use the calculator to determine how many ounces 2% of 100 is, weigh out that many ounces of Sn. Add Sn to pot.
 

Walks

Well-Known Member
I weigh all ingots ahead of time and write the of #pounds&ounces on each one. Add them up to make 50lbs, the (comfortable) size of my alloy mixing pot.

It was so easy when I had 1lb tin bars and 5lb pure lead ingots.

Or I got stuff from old Mr. Art Green.

I just have never made up COWW+2% Tin.
Just wanna give it a try.
 

oscarflytyer

Well-Known Member
not sure I can post it here, but I have a ready made (not by me/from the 'other site' iirc; used it for years now) Xcel sheet that has all the formulas worked out. Just plug in variables. Happy to email it if you want to PM me.
 

fiver

Well-Known Member
I'd try 1% first most ww's already have .5% tin in them.
well they used to.
if you got newer-like-90's on forward newer ww's,,, who knows?
about all you do know is they have about 2-2.5% antimony and maybe a trace of arsenic.
 

FrankCVA42

Active Member
Used to scrounge the dump at work for lead to make fishing sinkers. The splicer crews on the trucks used to clean out their trucks throwing out all the scraps and partially melted bars of solder so that got put aside for casting. That and a good friend from the splicer school used to save the hockey pucks of solder at the end of the week from the pots that the school ran for the trainees. Weigh the wheel weights and convert to ounces and weigh the scraps and close enough for gov't work. Cut the hockey pucks with either a cold chisel or what the splicer crews is something like a little meat cleaver. Very handy and is extremely thick on the back or spine to take the abuse from being hit with a hammer. Lately going in the garage is being likened to Christmas day. Found two 2lb bars of 50-50. Don't know what I'll find or forgot what had in the garage. Frank
 
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JWFilips

Well-Known Member
Any more I can only harvest brem pick up! I sort it out because I know the guys that shoot pistol often shoot commercial hard cast ( bhn 18) & the jacketed stuff is pretty close to pure lead! When I smelt I do each separate.... The ingots go into the pot 1 Commercial cast 2 parts Jacketed
This is fine for most I cast until I get to .25 and lower calibers! I then add about 2 % tin To help with small caliber fill out
 

FrankCVA42

Active Member
Old range I used to shoot at generally had one sunday a month when they did their high power matches and the pistol range was closed. Since most guys I knew shot those store bought hard cast 230 grain round nosed bullets in 45acp. I'd mine the berm. Made up a screen with 1/4" hardware cloth a rake and shovel and some plastic buckets. Considering I usually shot a couple hundred rounds at a time and my buddy did even more,there was a considerable amount of hard cast bullets laying on the ground especially after a heavy rain. I would sort out the 45 acp bullets and melt them separately. Still have two buckets left. Club president at the time got a big laugh when he heard I was mining the berm. Said that was the first time he'd ever heard of someone doing that. Hey,keeps me off the streets and outta the bars. Frank
 

Rockydoc

Well-Known Member
If your scale can read out in grams, that is the easiest way to calculate percentages. A kilogram of COWW is 1000grams. 2% is .02x1000=20grams of tin. I just chose 1000 as the example because it is easy, but odd numbers are easier with decimals also. Most calculations can be done in your head. For example say you have 2,436 grams of COWW. One percent is 24.36 grams, double that and 2%=48.72grams. You don't have convert pounds and ounces into all ounces or fractions. Easy-peasy.
 

462

California's Central Coast Amid The Insanity
Rockydoc,
My sincere apologies. :embarrassed:

Ric,
Thank you. Reckon I'm worse at math, as an adult, then I was as a high schooler.
 

RicinYakima

High Steppes of Eastern Washington
It is OK. Makes up for the "Newton" law about inertia I blew last winter. Happens to us all! Known as getting old. :D
 
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