K38 wadcutter gun rebuild

I'm rebuilding a K38 Masterpiece pre-14 frame as a wadcutter frankenfungun for club matches. Even though this gun will not go to a young, serious bullseye shooter with a steady hand and good eyes, I'd still like it to be the best we can make it.
The old frame has a new 6" -14 barrel, but I'm re-using the original cylinder. The gunsmith will slug the barrel and measure the cylinder throats for standardization. If we need to recut any throats I'd like to go for the best possible standard measurement.
I'm not even sure how to ask the correct question, but here goes: what should the relationship be for the measurements of the cylinder throats squeezing the bullet down to optimally fit the bore?
I'm sure the gunsmith will have an opinion, but I'd like to hear other opinions, too, so please let me know what you think.
I have heard .3575 throats for a cylinder shooting jacketed bullets, but not a measurement for lead bullets. I've been buying .358 bullets from Penn and Dardas, and they offer larger or smaller diameters on special order. I also want to "fit" the best diameter bullet to the cylinder throats and bore, so that's a factor, too.
Difficult question or is this a pretty standard set-up decision?
Thank you.

My cylinder throats have always been .358

of the few K38 I've seen or played with the cylinder throats were .358 

M14s were all .357

get yourself some pin gauges  and check each cylinder.. you can get them from MSC in pretty much any size you want.

I was taught that pretty much  your cylinder throats should be .001 over the bore diameter.. smiths run 357 so .358..  it is best to slug the bore though... I have seen some folks recommend .0005 over bore for the throat as in .3575


Manson 38 cylinder reamers are pretty std at .358 they come with several pilots


you can rent the reamers and pilots if you are only going to do one..

Thank you.