This is a very brief video showing how I turn case necks on the lathe. Ultimately, this probably works no better than any one of a number of dedicated neck turning tools but when you have the lathe available, why not take advantage. I do get very consistent and straight case necks.
In general, case neck turning is only of value in a tight-necked, match-grade chamber and in a rifle which is capable of showing any improvement. It is also useful if cases have a wide variation which causes variations in neck tension. If there is sufficient clearance in a chamber neck, there will be very little advantage to turning case necks; this especially if the brass is reasonably uniform.
