Backyard Casting

I like to keep a camera handy in case I see or do something interesting.  This weekend the RoadQueen was hanging out and she was excited when I suggested we take advantage of a sunny but cool autumn afternoon and engage in a little backyard casting operation.  She is a naturally curious person and firearms enthusiast to boot so I was more than happy to demonstrate this cool process for her.

In the course of my bicycle commuting and recreational road riding I have trained myself to watch for wheel weights cast off from automobile wheels along the streets and roadways surrounding my home.  These weights are made out of a lead alloy and are clipped to the rim of a car wheel to balance out the spin of the wheel and prevent vibrations at speed.  The small steel clip eventually loosens and the weights pop loose. I often find them lying alongside the road near railroad crossings and around intersections.  Any place the car is likely to hit bumps in the road these weights can be found.  I also have a theory that that a loose weight can be released from a rim by an under-inflated tire rolling during a turn and pushing off the weight.

Over the course of a year I find two or three a month.  Earlier this summer I lucked out and found two on the same commute.  The two weights were just a few feet apart.
    

Once I've collected up a few I'll put them in a cast iron pot and warm on my Coleman camp stove.  The melting point of lead is 621.5 degrees F or 327.5 C so it is fairly easy to get a hot enough temperature to melt this dense, heavy metal.  In the picture above you can see a couple of the weights just turning to liquid.  As the lead melts I can remove and discard the steel clips from the pot.

I have found that my cast iron patio wood burner makes an excellent crucible to do the actual casting work.  Using the rim of the wood burner's opening and a piece of fire wood as rest for my ladle and mold I have a sheltered work area that is easy to keep at a constant high temperature.  

The trick to casting is to keep the mold blocks in the perfect temperature window of not too cool and not to hot.  If the mold is too cool the molten lead will start to harden as it is being poured into the mold and not fill the cavity completely.  If the mold is too hot the ball will remain in liquid form and deform itself as it rolls out of the mold when the halves of the block separate.  When the temperature is just right the ball will harden and drop out perfect.  Doing the work as shown inside the mouth of the wood burner where a high temperature can be maintained makes the process flow smooth and trouble free. 

Over the course of the afternoon we produced 53 .54 caliber round balls from the wheel weights I scrounged from the roadways around my home.

So what do I do with these little silver spheres you ask?  Why shoot them out of my walnut stocked Rocky Mountain Hawken Rifle of course.

This afternoon I chose 10 pieces in a blind sample from the production run to check the weight of the balls using an accurate beam scale.  Here are the results measured in grains:

220.9

218.9

219.1

219.4

219.6

218.6

221.3

218.4

219.5

218.3

The maximum spread between these 10 sample is 3 grains.  Not much!  

1 ounce = 437.5 grains

1 gram = 15.43 grains