I agree with mathman. Get a concentricity gauge first. Then check runout on your case necks to ensure your sizing die and process is working properly. Once you know the neck concentricity is good, start checking concentricity of bullets in assembled rounds to check your seating die and process.
My preferred die set is a Lee Collet Die and a Forster seating die. I also like the Redding body die when the shoulder needs to be pushed back, but nothing wrong with just buying a Forster two die set and using the full length die to move the shoulder either.
Unless you get the Forster honed out it will be sizing the neck down a good bit more than necessary for Lapua brass in a 308.
