My cast bullet cartridges chamber just fine for the most part, although sometimes it seems to be a tight fit. When I chamber a round and then extract however, the bullet remains lodge in the bore and the brass is ejected, leaving a huge mess of powder. Its essentially a bullet extractor. Ive checked the width of the lead bullets and they are almost exactly the same width as the factory 8mm rounds I have which extract fine. The only thing I can think of is perhaps the overall length is an issue, I have an over length of about 2.86 inches. Perhaps, the bullets need sizing but they are the same width as my 8mm rounds that work fine... Ive searched for answers to this but couldn't find it, they are also lubed. Perhaps, out in the range it wouldn't matter since the bullet would be fired.