Re: cutting a barrel
The crown on your rifle is extremely important to accuracy. So if you want excellent results, here is one way. If it is a bolt gun you need to dive it with a tight fitting mandrel through the action in the lathe. Set up your steady rest as close as possible to the muzzle and still be able to set up a parting tool. Use your live center in the muzzle to center the barrel so it will run as true as possible. Keep in mind that the outside of your barrel is not concentric to your bore which your live center is in right at this point. I say this so when you adjust your steady on the barrel, do it just enough to support the barrel. I do not know your level of machining, but now you need to set up your parting tool square with the work. Set your lathe to its slowest speed, using a good grade of cutting oil, lube the work and cut off the barrel where you want. This is a slow process, and use plenty of lube. WD 40 is not cutting oil, nor is motor oil. Now the important part. The best way is to purchase a crowning tool for the specific caliber range and a set of removable bushings. Select the a bushing from the set that fits snug but not tight. Install it in a floating holder and insert the holder in the tail stock after you remove the live center you had there before. Using very high quality cutting oil, very slow RPM on your lathe, cut your crown deep enough to face across the whole muzzle. Now using a 60 degree center on that same snug fitting bushing, held in a tee handle supported by the dead center in your tail stock, make an inward cut by hand of about .010" to break the sharp edge which will prevent damage to your crown. Examine your work with a good set of magnifiers 25 power or so. If you wish, you may lapp the crown to a polished finsh, but not really needed if you did a great job in cutting using the proper tools and fluid. If you decide to go this route, the tools can be purchased from PTG or JGS, both makers of high quality tools and very helpful if you call them direct. At JGS speak with Cary, and at PTG speak with Dave. Either of these guys are about the nicest most helpful guys you want to meet, which I have met in person at the 2009 shot show. If you went to the expence of buying a lathe, get ready to start spending some serious money on tooling. No I am NOT advertising for these guys. I have bought and tried a lot of products, and am trying to save you from wasting your money and ending up disappointed. For all of you with a different way and opinion, just let me say there are different ways to go about doing anything, and I respect them all. This is my way, and if done properly, you will be very satisfied. Good luck, and I wish you good results any way you try it.