When to neck turn?

[Aim-To-Please]

G'day,
I have a fair understanding of why we neck turn. What I don't get is if you full-length resize and neck-turn you will gain something in concentricity. Neck turning would make sense to me if I were to neck size only (which I don't) so where's the advantage with neck turning if you don't shoot ammo fire formed for your chamber? That leads to my next question... Workflow: Should I clean and prep my brass then neck turn before FL resizing or resize, turn and prep.
"s"

 

[Straightshooter1]

G'day,
I have a fair understanding of why we neck turn. What I don't get is if you full-length resize and neck-turn you will gain something in concentricity. Neck turning would make sense to me if I were to neck size only (which I don't) so where's the advantage with neck turning if you don't shoot ammo fire sized for your chamber?
"s"

For when to neck turn, the big issue for me is the uniformity in the length of the neck from the shoulder-neck junction to the case mouth, where the stop on the turning tool is the case mouth. I want every cut into the shoulder to be the same and that can't be done if that measurement is not the same. So, the time to turn is whenever in the case prep process the neck length is uniform.

 

[RegionRat]

G'day,
I have a fair understanding of why we neck turn. What I don't get is if you full-length resize and neck-turn you will gain something in concentricity. Neck turning would make sense to me if I were to neck size only (which I don't) so where's the advantage with neck turning if you don't shoot ammo fire formed for your chamber? That leads to my next question... Workflow: Should I clean and prep my brass then neck turn before FL resizing or resize, turn and prep.
"s"

Some chamber designs include very tight neck diameters where neck turning is necessary.

As for when to turn the neck, it does need to be as straight as possible before attempting to turn. If the neck is out of round, dented, or has large runout, then you will want to correct it before you turn.

A neck with runout that is higher than the thickness variation, will not turn well, so get that neck as round as it can be before you attempt to turn. Another issue depends on your method. If the method uses a pilot, then it also needs to be at a diameter that coordinates with the pilot. YMMV

 

[jackieschmidt]

Keep in mind, the standard little hand held neck turner will produce necks that are closer in wall thickness concentricity than most can measure.

The vast majority of Benchrest Shooters, who shoot the most accurate rifles on the Planet, simply Neck the case up to fit their neck turner’s mandrel, turn the necks, and fireform the case. They then might trim them to a specific length if warranted.

It’s really that simple. The only people trying to make it more complicated are either trying to sell you something or are simply ignorant of the entire concept.

Also, with the quality of today’s brass, especially Lapua, many top of the heap shooters have started using Chambers that do not even require neck turning. This kinda throws a monkey wrench in the whole idea.

 

[piie]

Neck turning is usually only done once - when the brass is new.

To my understanding the reason you neck turn is not about concentricity, but to obtain even neck / bullet contact and thus, even and consistent tension for seating.
The way to do this is to push the uneven bits of the brass to the outside by first using a mandrel to open the neck to just larger than your neck turn mandrel.
Then you can either just skim off the high-points, or cut to a specific thickness depending on your rifle's specifications.
With the last "x" boxes of Lapua brass, the need to do any of this has decreased substantially.
There's been a bunch of tests done by people who can shoot way better than I can dream to that shows that the effect of concentricity on accuracy is questionable up to the point where the bullet is so skew it doesn't want to chamber.

 

[varget204]

Get a No Turn Neck Barrel, Save the time neck turning; for Loading & Shooting