Spindle size and muzzle threading

[jareese]

I spoke with another gunsmith the other day and he said he has a 2" spindle bore and does not need to remove barrels from receivers. In doing some testing on paper, I drew out a 2, 2.5, 2.55, 3, and 3.125" circles. I then screwed a stub onto a Rem 700 short action with an aftermarket PTG .250 recoil lug, centered it up to the witness mark in the center of the circles.
No way it would fit into a 2" bore without the lug hitting. 2.55 was very tight - I think there would be issues while dialing it in and stress would be put on the barrel. Am I wrong?

What spindle size is your lathe? Do you need to remove barrels from receivers in order to thread muzzles? What are you finding?

 

[GT Accuracy]

I spoke with another gunsmith the other day and he said he has a 2" spindle bore and does not need to remove barrels from receivers. In doing some testing on paper, I drew out a 2, 2.5, 2.55, 3, and 3.125" circles. I then screwed a stub onto a Rem 700 short action with an aftermarket PTG .250 recoil lug, centered it up to the witness mark in the center of the circles.
No way it would fit into a 2" bore without the lug hitting. 2.55 was very tight - I think there would be issues while dialing it in and stress would be put on the barrel. Am I wrong?

What spindle size is your lathe? Do you need to remove barrels from receivers in order to thread muzzles? What are you finding?

I think a lot of us have threaded a muzzle with the receiver on when it's a must do. I, and I only speak for myself, don't like to do it unless absolutely necessary. I made exensions for 16, 18, and 20 tpi barrel shanks to extend the workable length for my machines.

The problem with threading the barrel with it still on the action is that, if you coaxially indicate, you will have a mass that is large enough it will shake smaller lathes. Not to the point it's damaging but smaller machines, like the sharp 1340 and the Acra 1340 VS, can get a good shimmy going. On machines in teh 2,400 lb + range it's not nearly an issue. Turning your RPM down to 600 or less, even on the light machines, makes things much calmer.

 

[SKWERLZ]

I only have 1.24” spindle bore (restriction at collet shank area) so definitely action off for me.

 

[tobnpr]

I have a short spindle Sheldon so most barrels work just fine with the receiver outboard the spindle.

If it's too short a barrel for that to work, I'll stick a mandrel in the bolt raceway and do it between centers. If the crown doesn't need to be done, I use a crown saver or brass/delrin pin in the bore with the live center. If it needs crowning as well I set up in the steady with a sacrificial collar.

I've never pulled a barrel to do muzzle work.