On Sunday, October 2, 2011 9:28:34 AM UTC-7, Tom Gardner wrote:
On 10/1/2011 11:08 PM, azotic wrote:
//
Silver at $30 a troy ounce, them be some pricey projectiles. A graphite
mold made on a cnc mill would work just fine.

Silver's lighter than lead, I'll do the math to match pressure and
velocity using the lighter slugs. I like your mold idea but I'll need
provisions for some lube I think. Silver's a lot harder than lead,
especially if I use Sterling, mayme I won't need lube...hmmmm.

It's necessary to use non-pure silver if you want to cast it; otherwise
the stuff spits. Sterling is usually (7.5 percent?) copper added to the
silver, and that's enough to stop spitting (something to do with
dissolved oxygen, I hear).

The same jewelry-supply places that sell silver shot, will have a
line of appropriate waxes and ceramic moldmaking items.
Your dentist probably knows a local shop that casts precious metals,
already, and you might save time by getting them to do the hot parts.