Totally agree Chris. It's best to look completely around the COAL # and go with CBTO # when working up a load unless the mag. length comes into play.Sizing as the instructions state will allow your rounds to fire safely in any rifle of the same caliber and using the measurements from the load books. Load books seating bullet lengths in Over All Lengths which isn't the best for really accurate rounds do to bullet tips being off. In reloading your in most cases looking for a custom fit for your chamber and barrel. It is a very safe hobby as long as you follow the directions , ask questions when unsure of something , try calling the manufacturer , ask questions on forums . As time goes on you'll try different dies , gauges and every new gadget out there. Hope you have space in your gun cabinet . Load Safe.
Chris