I have never reloaded 303 before, and I bought these dies off ebay. They appear to be new. I have removed the decapper pin, as I use a universal decapper. As you can see if the pics work properly, both dies have inserts. I am needing to know how to adjust these on both. Have never seen a neck sizing die, but don't think this is one, as there is really no adjustment other than how deep the decapper shaft goes in. Suspect it is some kind of universal body with an insert for 303(clearly marked insert). The seater die has a window in it ! Also has an insert marked 303 Brit. Insert moves freely when round is run into it, until it meets the seeter, which is adjustable for depth. The insert allows the bullet to almost completely enter it Any advise on these ? Just set up and use as normal dies ? Probably much angst about nothing, but better to ask here first for the experts advice-Thanks-jb12k