Molten brass will not stick to a mold unless its almost cherry red, we cast brass at work sometimes using steel molds......Flux is your friend.
As far as being undersized.....if you go back to post #1 thats one of the main things I was asking.
Again, this is a "why the hell not" project, I am not worried about lead in the least, not hunting dangerous game, and even if I toast a mold.... oh well it's an old cheap one anyway.
Nobody here has done anything knowing it was probaby not going to work, but you just want to try anyway......?
The best shot I ever made was an accident