Needing alittle help

[vls22250]

Guys I am in need of some help. I am trying to thread my first barrel and I have ran into a snag. I am using the grizzly rod method on a factory remington varmint barrel. What is happening is I can get the barrel to run true at the muzzle and 2.5 inches in but I am getting a difference of .006 when moving the rod between those 2 spots. It will run right at 2 tenths of concentric for that 2.5 inches so I don't know if this normal or I if I am missing something. Thanks for the help.

 

[J E Custom]

Guys I am in need of some help. I am trying to thread my first barrel and I have ran into a snag. I am using the grizzly rod method on a factory remington varmint barrel. What is happening is I can get the barrel to run true at the muzzle and 2.5 inches in but I am getting a difference of .006 when moving the rod between those 2 spots. It will run right at 2 tenths of concentric for that 2.5 inches so I don't know if this normal or I if I am missing something. Thanks for the help.

Most of the smiths build/have a spindle spider that goes in the spindle opposite end of the chuck
that centers the tail end (Or the muzzle)of the work to true it in the spindle.

This is nessary to true the bore from one end to the other and it also prevents whip while turning
the work.

Mine is simply a collar that threads into the spindle and has 4 adjustment screws.

You can use your range rods on both ends for alignment. Once both ends are perfectly aligned
the barrel never comes out of the lathe until crowning (All threading, fitting, chambering and headspacing are done).

J E CUSTOM

 

[vls22250]

Sorry I should have specified I am using a spider on the outside of the head stock. I just went back and forth adjusting the 4 jaw chuck and the spider to get those 2 points dialed in. Now with those 2 points dialed in and not moving the indicator when I run the rod back and forth between those 2 points is where I am getting the .006 difference I hope I am making sense.