Depending on the gun being chambered for, you may or may not need to cut a rim recess in as barrel. Breakopens headspace in the barrel, some bolts headspace in the face of the bolt as do most semi auto's, others like CZ bolt guns do some in each.
Depending on the use of the rifle some chamber designs are more forgiving with cheaper ammo than a chamber designed strictly for match ammo.
It's good to talk to the builder about your intended useage.
A lot of builders will start with a stock reamer design and order it to their specs, maybe changing one or two of the specs.
Dave Kiff @ PTG is always on top of the current trends for competition.
Bob, a Bentz reamer has tapered walls and is ment more for semi-autos, but retains a match throat for engraving the bullet. It works well for a lot of applications and shoots most ammo well. Because of the tapered walls it is seldom used in true competition rifles. A Win 52 chamber is just an older factory match design, the specs should be on the link by Landy's post.
Kim