My most interesting/challenging project was re-barreling my T. Turner 500-450 3 1/4" BPE double. Too many cordite powered nitro-for-black loads had severely washed the barrels. I started by making a mono-block then turned the barrel profiles and pressed and TIG welded the barrels into the mono-block. Along with all the usual small parts I had to make a fixture to hold the material to make the top rib and one to hold and regulate the barrels while I soldered them up. I only worked on it when I wanted to so it took several months to complete but I think it turned out OK.
Attachment 300999Attachment 301000Attachment 301001Attachment 301002