Neck Turning Question

[sandbar782]

Can anyone that has experience neck turning let me know the order in which you do it in the process? I assume you would size and trim the brass 1st, then turn the necks. Add as much detail as you like. I a pretty good handle on reloading now and would like to take this next step. Thanks for your help.

 

[Mikecr]

Some things with my normal turning:
-I only turn new/unsized brass, as this best fits turning mandrels, full length.
-I turn down neck FL and onto shoulders a small bit(my opportunity to mitigate donuts).
-I do not trim necks first/for turning, or use turning stops. I can easily eyeball ~1/16" onto shoulders which is plenty enough. I trim to correct length only after fireforming.
-I hold the turner body in my hand(floating) while the case is held and spun by a 'case lathe'.
-I use Mobil1 for turning lube, and cool the turner mandrel/cutter with a swish & brush in a heavy small bowl of alcohol resting in a larger pan of ice water.
-After turning I polish the neck a bit with 000 steel wool while it's still on the lathe. This is so I can confirm neck thickness to near .0001".

As far as setting, I'm pretty old school trial & error with a feeler gauge and a couple culled cases. Newer turners provide standard incremental adjustments(I use Sinclair's NT-4000), which is nice but no faster really.
When things are abnormal for turning (up/down sizing, or re-forming neck involved) the trial & error takes a little more effort as I still turn the brass while new/unsized.

It's not an exact science, many ways to skin the cat. Luckily, it takes a lot of effort to screw it up

 

[sandbar782]

Thanks for the tip.

Do you or anyone else ever turn fired brass. I would think a once fired piece that has been FL sized and trimmed would push all the thickness variation (the thing turning the neck is targeted at removing) to the outside. Cutting this variation off by neck turning would then provide uniform neck thickness and already have a concentric ID because the FL sizing button made it this way.

Just curious because all the brass I have is fired at least once; and I have a lot of brass. Opinions or other options?

 

[FEENIX]

Thanks for the tip.

Do you or anyone else ever turn fired brass. I would think a once fired piece that has been FL sized and trimmed would push all the thickness variation (the thing turning the neck is targeted at removing) to the outside. Cutting this variation off by neck turning would then provide uniform neck thickness and already have a concentric ID because the FL sizing button made it this way.

Just curious because all the brass I have is fired at least once; and I have a lot of brass. Opinions or other options?

First, use new brass as the best starting point. Second choice would be once fired.
If you go beyond that, necks must be annealed, as they become too hard for the multiple step process.
Once fired brass gives you the advantage of a fire formed case, and hopefully
some neck growth.
(Neck Turning Made Easy)

 

[Mikecr]

Do you or anyone else ever turn fired brass.

This is among what I consider abnormal for turning.
Doing it well means a bit more trial & error with more culled cases.

The reason this isn't totally simple is that things get more & more dynamic with every energy added(from new condition). There is changing dimensions, angles, spring back, and thicknesses in every direction of it. And once brass is fired it becomes a new local cartridge, that will never be in original form again. It could be good for turning or real bad for turning.

 

[sandbar782]

Thanks for all the comments; this is exactly the information I was looking for. My take away is that neck turning, to be done properly, should be completed on brand new (never fired) brass. Once fired brass should only be considered as 2nd option, and is not nearly as desirable. All other brass would require annealing before neck turning, and this would be considered highly undesirable for turning.