Was talking to a good reloading friend of mine today, and he posed a question that I haven't a clue how to answer. He has no internet access, so I said I would ask the world of knowledge that you all have. He wants to neck size .223 down to .17 HMR to get away from the rimfire cartridges. He has been reading in reloading books to find the right procedure, but I told him of the millions of dollars of advice that I have gained from the forums and said I would ask. What you all think? Thanks in advance for the advice.