I ground up a quarter inch high speed tool bit with a radius years ago and am still using it today. I run my lathe in low back gear and plunge cut feeding by hand. The only down side to this type of crown,unlike a benchrest crown,is that you have to dial in the muzzle.
I ground up a quarter inch high speed tool bit with a radius years ago and am still using it today. I run my lathe in low back gear and plunge cut feeding by hand. The only down side to this type of crown,unlike a benchrest crown,is that you have to dial in the muzzle.
explain that...are you talking od vs bore ??
explain that...are you talking od vs bore ??
I guess I didn't make myself very clear so will try again. I took a quarter inch high speed tool bit and ground a female radius. The radius was large enough so I can crown a barrel up to about .750 by blending it in by using the cross feed and the compound together. In other words it is not a specific radius but it looks nice. With this type of crown I dial the barrel in on the inside diameter of the bore. With a flat "Kelbley style" crown I'm not as particular. Hope this makes sense to someone besides me!
Check with the tool makers. Someone makes a piloted reamer made just for this type of crown. I know because I have one in my tool box but I cannot get there from here to look at the name on it.
I have it for one job on an old Newton rifle that I have been procrastinating on for about 4 years.
Mine is a number 2 shank I'm sure they make a number one.
I tried to post a pic but the upload failed.