What Steve said & I'd have to agree. Many of the posts, including my own, have identified cartridges people would like to build a double in but I don't think any have identified an area that another similar cartridge has not already been chambered for. Certainly some are not easy to come by today & that would be an excuse to chamber for another. Maybe the thread should have been "What cartridges not in current use you would like to build a double in?" 318WR Flanged

Steve