Factual error: Horace was not holding the shotgun properly - the kickback would have not only made him miss Gillman, but it would have knocked Horace to the ground.
Factual error: When the silver bullets are being cast, the silverware thrown into the melting pot appears to melt instantly, the bullets come fully cooled and hardened out of their mold in seconds, and are already fully formed and polished, straight out of the mold.
Suggested correction: We only see Rudy put in a few pieces of the silverware, we don't know how much he already melted. The casts come out dull when he shakes the mold, what you are seeing on the table are the bullets he already made.