I had a piece of scrap wood, 1x2 I think, that I drilled a shallow hole 1/2 way through near one end. The hole was just larger that whatever caliber brass I was using. Then I zip-tied a sharpie to the wood block. I could put in a loaded round in the hole, give it a quick turn and get a nice stripe around the case. It worked fine for a non-tech, cheapskate solution.