% Arsenic needed for heat treating

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% Arsenic needed for heat treating

Post by aseedylot » Wed Feb 19, 2014 11:00 am

Just bought a mold from Mountain Molds and it looks wonderful. I am now on the search for a casting alloy. Seems that my best option is trying to match WW through combinations of root metals alloys and lead shot.
My big question is what percentage of lead shot would it take to enrich my alloy with arsenic so I can heat treat the bullets. Reading the internet somebody said 1 pound shot for 20 pounds alloy. My goal is between 1800 to
1900 fps with my bullets. Any thoughts would be great.


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Re: % Arsenic needed for heat treating

Post by mtngun » Wed Feb 19, 2014 12:57 pm

A Dennis Marshall article I'm looking at says that wheelweight typically has 0.17% arsenic. The question is, how much arsenic is in lead shot? The manufacturer's MSDS gives a wide range that is not precise enough for our purposes. However, I've heard that 1% arsenic is typical.

To add to the confusion, arsenic is a natural contaminant in lead so chances are that whatever alloy you are starting with already has trace amounts of arsenic in it. :roll:

The 1-20 formula for adding shot sounds quite reasonable and I'd be surprised if it didn't work. The % of arsenic is not that critical for heat treating.

If you are going to be mail ordering your metal, check ebay. Wheelweight seems to sell there for about $1.50 pound, which is a rip off, but probably no worse that any other mail ordered metal. http://www.ebay.com/itm/30Lbs-Used-Lead ... 1c3cc4b3de

It's sad that wheelweight is hard to come by in some parts of the country. I'm so old, I can remember when service stations and tire shops were glad to get rid of it. :lol:

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