I think I found a way to ask my question that will be better explain my confusion.

 

  So I have the RCBS 38/357  38-158-SWC mould and I am loading it in several guns. Revolvers and lever action rifles. The dia for 38 cal is .357" but one normally sizes the cast bullet .001" or .002" bigger. I have a old Ruger Vacaro is .357 mag that needs the bullets sized to .359" all the rest of our 38cal guns take the .358" sizing

  I am using the Hornady brand of gas checks and using the Lyman gas check seat tool in my Lyman 4500 lube and sizer.  I put the Lyman GC seat tool in the lube and sizer and place a GC on the bullets shank and then place the cast bullet into the size die lip and then my wife pulls the handle so the top pounch makes contact with the bullet. I then pull the handle until I feel the GC seat on the bullet. I then raise the handle and most of the times the bullet with GC installed lifts out of the size die some. We remove it and set it aside and seat the rest of the GC. 

  Then we remove the Lyman GC seat tool and plug in the heat cord for the lube and sizer. Once the lube is heated we lube and size all of those cast bullets.

  My question is; do I used a different diameter size die to install the gas check on the bullet we will be sizing to .359" ? or is the diameter of the size die to install the GC's going to be the same? And I just use two different size dies the .358" and .359" for the size and lube portion?

  I hope I have explained this quandary well enough that ppl will understand what I am confused on. My wife and I plan to put gas checks on the 6.5's and 25cal and 38cal and the 45cal cast bullets we casted last night on date night.

  

GOD, United States of America, US Marine Corps, Family, Self