I have a few KKM barrels. One has so little freebore, I litterally can't load any of my cast loads. To get cast to work in that barrel my OAL's are ridiculous. Another one of my KKM barrels came with so much freebore, I can load just about anything, as long as I want, similar to a stock barrel.
I believe KKM will make the barrel anyway you want. It seems the defaults are the lands pretty close to the chamber and a throat right at the bottom SAAMI spec. I think the barrel I got that has all the freebore maybe was one they cut for someone that ended up not getting shipped. Guess which one of my KKM barrelks gets the most use?