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Sequence Step for Neck Turning?

Been loading 308 for several months for F T/R, but now trying to really up my brass prep consistency game with Redding comp dies, neck turning tool, and concentricity gauge.

My question is where neck turning falls in the brass prep sequence.

In my mind I would neck size, then full length for shoulder bump, then turn. But if the expander mandrel produces a neck tension looser than my neck bushing, do I then neck size again after turning? And if I do that, wouldn't some moving brass possibly affect my shoulder bump? Help, I'm in a do-loop and can't get out!

Or is the answer simply that the expander mandrel won't be looser than the .001 - .002 tension?

Thank you!
 
Been loading 308 for several months for F T/R, but now trying to really up my brass prep consistency game with Redding comp dies, neck turning tool, and concentricity gauge.

My question is where neck turning falls in the brass prep sequence.

In my mind I would neck size, then full length for shoulder bump, then turn. But if the expander mandrel produces a neck tension looser than my neck bushing, do I then neck size again after turning? And if I do that, wouldn't some moving brass possibly affect my shoulder bump? Help, I'm in a do-loop and can't get out!

Or is the answer simply that the expander mandrel won't be looser than the .001 - .002 tension?

Thank you!

I will fire form the brass first to bring the shoulder up to the chamber dimensions, also the fire forming will bring the exterior axis of the body and the neck into alignment. I'm also annealing after every firing, which helps minimize the spring back when running an expander mandrel through the neck. So, after the second firing, I'm ready for turning the neck and will FL size the cases without any expander ball and then run the expander mandrel (to move the variances to the outside) that's .001 greater in diameter than the turning mandrel.

Some people like to turn the necks first thing and then turn it again after the fire forming process. But I like to have fewer steps and I find I get just as good results doing as I do.
 
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1. Decap
2. SS Tumbler
3. Uniform Pockets
4. Bushing Neck Size or Bushing Full Length Size
5. Expand Neck to Mandrel Size
6. Turn Necks
7. Tumble again to Remove Lube
8. Chamfer, Trim and Debur
9. Prime
10. Add Powder
11. Seat Bullet

Between steps 2-4 you need to anneal
 
Expand virgin necks w/mandrel
Turn
Chamfer, deburr
Tumble clean
Prime, Load, Fire form
Tumble clean
Burn
Full length size w/bush
Tumble clean (brief)
Prime
Load
Conquer!
 
JDSwim3,

On new brass, anneal before any sizing operations. On old brass, anneal after initial cleaning to remove crud and before any sizing operations.

HTH,
DocBII
 
In my mind I would neck size, then full length for shoulder bump, then turn. But if the expander mandrel produces a neck tension looser than my neck bushing, do I then neck size again after turning? And if I do that, wouldn't some moving brass possibly affect my shoulder bump? Help, I'm in a do-loop and can't get out!
1. I have neck turned new brass and fired brass, either way can work. Based on the case head to datum, you will need to adjust your cutter.
2. I much prefer to FL size rather than size the neck with a bushing. The bushing leaves a portion of the neck unsized and this will result in that portion having more material removed when you turn the neck.
3. I find the expander results in less neck tension than I normally run (about 0.001" and I normally like around 0.002"), so after turning I size the neck to the diameter I want for the neck tension.
4. Adjust your die so you don't bump the shoulder.

but now trying to really up my brass prep consistency game with Redding comp dies, neck turning tool, and concentricity gauge.
You will learn a lot about your process by checking concentricity of fired necks, sized necks, and after bullet seating. I foolishly ass-u-med that the Redding comp seating dies would give excellent concentricity for bullet seating. Not so. I now seat in 3 steps turning the ctg approx 120° for each seating. Cut my bullet runout by ~2/3.
 
Can anything be gained by turning the necks when using a factory rifle, which is not cut for a reduced case neck diameter?

I have several factory rifles for which I use a bushing die when forming. after firing cases for the first time, I then anneal them and run them through the die and seat a bullet. When checking concentricity, I find runout to be minimal.

The cases seem to stretch a bit and need trimming which I suppose comes from the bushing die reforming it.
 
Can anything be gained by turning the necks when using a factory rifle, which is not cut for a reduced case neck diameter?

I have several factory rifles for which I use a bushing die when forming. after firing cases for the first time, I then anneal them and run them through the die and seat a bullet. When checking concentricity, I find runout to be minimal.

The cases seem to stretch a bit and need trimming which I suppose comes from the bushing die reforming it.

In obtaining consistent neck tension and lower runout, I would think that would help with any barrel . . . huh???

When my .308 had its factory barrel, I got some significant improvement by turning the necks, so . . . in my case the answer is "yes". :)
 
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Can anything be gained by turning the necks when using a factory rifle, which is not cut for a reduced case neck diameter?

I have several factory rifles for which I use a bushing die when forming. after firing cases for the first time, I then anneal them and run them through the die and seat a bullet. When checking concentricity, I find runout to be minimal.

It depends on what you are trying to do. Neck turning does help with concentricity and consistent neck tension. Could you see the difference on target with your rifles? Only you can answer that. For me it was more consistent groups and less than a tenth of an inch of improvement in 100 yrd group sizes. Substantial for me.



The cases seem to stretch a bit and need trimming which I suppose comes from the bushing die reforming it.
 
On virgin brass that has been full size, do you trim them ? Thank you.
Virgin brass does not usually need to be sized or trimmed unless you're working with a wildcat or unusual chamber. Measure a sample of them to check the OAL compared to SAAMI. Try an unloaded case in your action.
 
Speaking of neck turning does anyone know the size of the screw in the handle for the Sinclair NT-1000 turner unit? I removed it to try and get some extra screws from a local supply shop. The screw is damaged and won't go back in. I've contacted Brownells several times, but have yet to get a rsponse.
 
I'm really wrapped around the axle on this, and it's driving me nuts.

Help, please!!

1. Firing the brass expands the neck beyond the ID of the 21st Century expander mandrel and turning arbor (yes, I'm on a factory barrel for now)
2. So I neck size down in order for the expander mandrel to do its job and seat on the turning mandrel without play
3. But the expander mandrel creates a neck ID that is too loose, and allows the SMK projectile I'm using to slip below my desired CBTO
4. So now I feel like I'm forced to neck size down again for proper tension and seating depth

Obviously that's way too much working of the brass, especially since I don't anneal yet (Santa has my wish list).

Thank you!
 
I'm really wrapped around the axle on this, and it's driving me nuts.

Help, please!!

1. Firing the brass expands the neck beyond the ID of the 21st Century expander mandrel and turning arbor (yes, I'm on a factory barrel for now)
2. So I neck size down in order for the expander mandrel to do its job and seat on the turning mandrel without play
3. But the expander mandrel creates a neck ID that is too loose, and allows the SMK projectile I'm using to slip below my desired CBTO
4. So now I feel like I'm forced to neck size down again for proper tension and seating depth

Obviously that's way too much working of the brass, especially since I don't anneal yet (Santa has my wish list).

Thank you!
It’s important to get the mandrel that the neck turning manufacturer makes for that tool. Contact 21st Century and ask them for the proper neck sizing mandrel...and start annealing, with a battery drill and a 1/2” socket if you have to.
 
It’s important to get the mandrel that the neck turning manufacturer makes for that tool. Contact 21st Century and ask them for the proper neck sizing mandrel...and start annealing, with a battery drill and a 1/2” socket if you have to.

I ordered the complete lathe kit from 21st Century, so yes, I do have the manufacturer's expander and arbor. Disappointed that it's opening up ID beyond needed tension. Since it now seems that I'll have to neck size a second time for tension and seating depth, no question I have to anneal. So I sucked it up and have an Annealeez on order. Couldn't cough up the bucks for Mike's or Bench, and certainly not for the AMP.
 
So you're using a factory barrel? What exactly are you shooting? Some factory rigs are "OK" but rarely competitive. Sounds like you chasing your tail, to be blunt.
 

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