Do you have a 150 foot shot tower? Couldn't resist that one, sorry. The factories use air as a coolant before spashing down to prevent shot deformation. The process will have a lot of problems for the individual but would be interesting. Wheel weights will be harder shot and I'm afraid that any method of home production will be hard to come up with round shot resulting in a lot of fliers. I've tried wheel weights for casting bullets, sinkers, and jigs, but it has it's own problems with casting and I usually use it mixed with pure lead to get good castings. Good luck.