Here is a nice example of the rare and interesting Lyon and Boyd tool. Our own director, Tom Quigley, recently reported on a survey of these tools in which he summarized the attributes of about 25. In that survey, he noted only one in 45-60 caliber. Interestingly, another 45-60 recently showed up on our message board; a nice example of how sharing information helps develop the information base upon which we all depend for enjoyment of our hobby. Tom's article may be found in The Gun Report, volume 48, number 5 (October 2002), p. 34-43. In addition to the survey of tools, he provides much interesting background information on the makers, and patent documents are also presented.