Bloodnative,

Properly adjusting a full length sizing die foe a belted case can be a pain. But when once done you can full length size a case so the bolt will close on a case with just a little feel and that should take care of it for you. If available, I'd suggest you get a neck sizing die and forget about full length sizing. The belted case was designed by H & H for the case to headspace on the belt. This was necessary due to the powders used at that time. (Cordite) A lot of the new magnum cases were made with the belt because of being identified with Magnum performance. The belt hasn't been necessary for about the last 75 years or so. The non-belted case, will handle the pressures of magnum performance, and are easier to work with. If it were me, I'd let the belted cases die a natural, if belated, death. Good luck and God Bless.