up on the top is a link to the Knowledge Base. If you check there, you will see a couple categories, one of them is Reloading, in there is a sub category for Hornady factory data, inside that is a data sheet showing the dimensions and 2 links to PDFs containing factory load data, one is the old data that came out right after the 450b was released, the other is a newer load sheet.
Here's a Link to the newest data, but I urge you to dig around in the knowledge Base a bit. There is some other good info there, and it will soon be filled with even more good stuff.