24 April 2019
Tom, a few years ago (42 if my arithmetic is right), I did my first casting; it was for my .357 using a friends newly bought mold and nearly pure lead he had. Cast the bullets, loaded the cases with "light" .357 loads, and went to the range. After a box of bullets I could not hit the target, and looking down the barrel I had made a smooth bore. Borrowing a few rounds from the guy next to me, I shot a cylinder of jacketed bullets, and the bore looked proper with lands and grooves.
Now, there were plenty of things not done as well as they should have been, like having tin and antimony in the lead to have a hardened bullet, putting lubrication in the lube grooves, shooting a light .38 special load, you know, just a few minor things like that. BUT, the jacketed bullets did get most of the lead out, who knows what pressures were developed in the first couple rounds. After I got home I used my Lewis Lead Remover and did get a lot more lead out, but starting with a smooth bore there was a lot of lead to remove. I don't know if more shooting would have cleared all of it out, I wasn't going to borrow enough bullets for two cylinders full.
My long ago experience is it helps in the field, but attention needs to be applied when returning home.