Hi Tim,
I just measured the moulds and they are 2.125" diameter. What I meant was that the moulds were advertised as being 2.25", however, they are not.
Yes, the moulds are cast aluminum. The vent holes are 1/8" in size and not much (if any) lead flows from them. The moulds aren't a 100% tight fit. Putting mould blocks together and holding them up to the light you can see where there is some light comming through.
The sprue holes are approx .30" in diameter with the opening being just barely over an inch in size.
You can buy them online at
http://www.tyeetackle.com/ . The proprietor claims he supplies these moulds to Cannon Mania for sale in the US.
All in all, they aren't bad moulds at all. They take a long time to heat up and you'll be lucky to get the pour cavity hot enough to keep the lead from solidifying before you are done pouring.
Throw away the supplied spring metal clamp that is supplied and use a 4" c-clamp instead. The spring metal clamp gouges the aluminum and marks it up quite badly, even when the mould is cold. When the moulds are properly heated the spring clamp would really marr up the aluminum.
I've been using a standard Lyman bullet casting ladle with horrible results. I just bought a stainless steel soup ladel that should be large enough to contain the required lead for a single pour into the mould. Hopefully this will result in less time required to pre-heat the moulds and (more importantly) to have a properly cast lead ball.
Jeff