ok, here is what i have come up with and the process i used to get my results.
first i took a spent 9mm case, melted some pure lead sinkers down and poured in it. i then used my puller, to extract the slug from the case.
then i took the slug and gently tapped it into the barrel, about half way in, then back out the same way.
i took my dial calipers and measured the slug. i came up with .354
i then measured my boolits and they are a .356
is the .356 too large? the slug i made fit very loose, as far as tapping it in the barrel, i done with the palm of my hand.
the .356 boolits are hard to tap in and i have to use a hammet to even get it going.
so now i will cast a pure lead boolit in my mold and redo my slug test because i really dont think using the spent case has given me an accurate measurement.
i will soon return with more information.