I've followed several threads concerning zinc contamination in casting alloys. I've also noticed that some old bullet molds used a zinc washer or gascheck.
My assumption is that zinc makes casting difficult but it isn't too hard to shoot through a gun barrel.
Is the problem bullet fillout? Zinc is widely used to make die-cast parts. I know that process creates a lot higher pressure head, so if a pressure casting method were used to cast bullets from zinc-contaminated alloy, would the bullets be OK despite their lighter weight?
Any comments?