Inside/Outside Case Neck Turning On A Budget - .308 Win

[hrgriffin1]

Hello,
I am rather new to Reloading however, I believe I have come up with a somewhat practical method to neck turning both the inside and outside of the case neck.

Inside Neck Turning
1. Anneal brass. This softens the brass allowing turning the inside of the neck to be a little easier.
2. Size the brass. I remove the mandrel from my FL sizing die for this step.
3. Expand case neck using 21st Century expanding die with .309 mandrel. This .309 expanding mandrel is the largest 30 Cal expanding mandrel I could find. I believe .3095 & .310 would be ideal. I say this because LE Wilsons Case Neck Reamer is meant for fired rounds so it is .002-.003 larger than whatever caliber you use it for.
4. Use LE Wilson Case Trimmer with 30 Cal Inside Neck Reamer to turn the inside of the case neck. This step is the slightly unpractical part of this process because it takes forever. LE Wilson doesn't make a power adapter for their case neck reamer. If anyone knows of someone that makes an adapter I would really love one.

Outside Case Neck Turning
1. Resize the brass with mandrel or sizing ball removed. This is an important step given we expanded the case neck to turn the inside.
2. Expand case neck using 21st Centuries Neck Turning Mandrel.
3. Turn the outside of the case neck with whatever device of your choice, I used a Hornady Case Neck Turning Tool. There is a trick I found to the Hornady Case Neck Turning tool is you don't want to over-tighten the case holder. When I cranked on the case neck holder is when I would get a lot of wobble.

Using the steps I just laid out I have been able to achieve consistent thickness only varying a +/- .0005! I am using a iGaging EZ-Data Ball Micrometer to verify my claim, and taking 5-6 measurements on each case neck.

Let me know what you think of my method, and if you know anyone that sells a power adapter for the LE Wilson Case Neck Reamer Tool (my hands are ripped to shreds after 20 cases).

​

UPDATE: I did find out that 21st Century has .3095 & .3100 Expanding Mandrels they just hadn't listed them on their website, so those are now on order.

 

[Dusty Stevens]

I only know folks that outside turn. Why are you turning the inside? I like the smooth drawn finish inside

 

[hrgriffin1]

It really boils down to concentricity. If you only turn the outside of the case neck you are only addressing half of the equation. Outside neck turning allows for better concentricity of your brass in the chamber. Inside neck turning allows for better bullet seating concentricity.

 

[memilanuk]

My understanding is that factory cases - all brands - are annealed during the forming process. Some (Lapua, etc.) leave the color change as is, other brands do a subsequent final polishing step that hides it... but they all do it. Hence, you're not really accomplishing much by annealing new out-of-the-box brass - but if it makes you feel better, go for it.

I'm curious what kind of neck thickness consistency you were getting without the inside neck reaming? I don't have anything the queue to turn right now, but I'm pretty sure I get better consistency than that with just a mandrel and outside neck turning.

 

[hrgriffin1]

I was using unfired Lake City Brass that I pulled the bullets from, then loaded and shot with some crap bullets I didn't like so I could spend the factory primers. I couldn't shoot the projectiles at my range so I had to pull them.

 

[hrgriffin1]

My understanding is that factory cases - all brands - are annealed during the forming process. Some (Lapua, etc.) leave the color change as is, other brands do a subsequent final polishing step that hides it... but they all do it. Hence, you're not really accomplishing much by annealing new out-of-the-box brass - but if it makes you feel better, go for it.

I'm curious what kind of neck thickness consistency you were getting without the inside neck reaming? I don't have anything the queue to turn right now, but I'm pretty sure I get better consistency than that with just a mandrel and outside neck turning.

I have actually been getting very good consistency on target 1/4 MOA or better. In an effort to improve even further, I have fallen down a deep rabbit hole...

 

[hrgriffin1]

Thickness consistency was all over the place when I was only turning the outside of the neck and using an expanding mandrel. I couldn't find a tool that would turn the inside and outside of case necks that weren't over 2k which led me to use the case neck reamer to turn the inside of the neck, and the Hornady tool for the outside.

 

[Ned Ludd]

It's all about perspective. I have little trouble achieving 1/4 MOA precision or reasonable ES/SD values with my .308 Win F-TR rifles, all of which have no-turn neck chambers. Thus, I do not choose to turn necks, as I don't perceive the benefits of neck turning to be worth the effort involved.

If you're interested in .3095" or .3010" mandrels to use with your approach, check here:

Expander Die Body

Expander Die Body Introducing the much anticipated Generation X Expander Die Body with viewing window! Set up of an expander die has not been easier! The viewing window allows the user to set the die to allow for optimal mandrel use without “bottoming out”. Machined out of 7075 Aluminum and...

21stcenturyinnovation.com

Caliber Specific Expander Mandrel Kits

Our caliber specific expander mandrels are available in .0005” increments in calibers 22 to 338 and will range from .001” above bullet diameter to at least .003” below bullet diameter depending on caliber. This will allow the reloader to find proper neck tension to fine-tune their loads. The...

21stcenturyinnovation.com

 

[hrgriffin1]

It's all about perspective. I have little trouble achieving 1/4 MOA precision or reasonable ES/SD values with my .308 Win F-TR rifles, all of which have no-turn neck chambers. Thus, I do not choose to turn necks, as I don't perceive the benefits of neck turning to be worth the effort involved.

If you're interested in .3095" or .3010" mandrels to use with your approach, check here:

Expander Die Body

Expander Die Body Introducing the much anticipated Generation X Expander Die Body with viewing window! Set up of an expander die has not been easier! The viewing window allows the user to set the die to allow for optimal mandrel use without “bottoming out”. Machined out of 7075 Aluminum and...

21stcenturyinnovation.com

Caliber Specific Expander Mandrel Kits

Our caliber specific expander mandrels are available in .0005” increments in calibers 22 to 338 and will range from .001” above bullet diameter to at least .003” below bullet diameter depending on caliber. This will allow the reloader to find proper neck tension to fine-tune their loads. The...

21stcenturyinnovation.com

I actually just ordered the 21st Century .3095 & .3100 Mandrels just now after contacting their customer service and inquiring if they ever planned on offering them.

I have seen much better ES/SD after building my own induction annealer, and annealing after every firing.

I believe my next attempt to achieve better results will be with the Auto Trickler V4 (hopefully a Christmas gift), and trying out some 308 Palma cases.

 

[Dave M.]

Thickness consistency was all over the place when I was only turning the outside of the neck and using an expanding mandrel. I couldn't find a tool that would turn the inside and outside of case necks that weren't over 2k which led me to use the case neck reamer to turn the inside of the neck, and the Hornady tool for the outside.

The expander mandrel should match the brand of turner you are using. For instance I’m using a K&M expanding mandrel with the K&M neck turning setup. They should be a matched pair. Also +/-.0005” isn’t very tight. My ball mics read down to the hundred thousandths place and there is NO WAY my necks measure over the full range of .001”. That is a lot. Perhaps you meant +/-.00005”
I think turning the inside necks is a waste of time. And honestly most people will tell you that Hornady turning setup is one of the most inconsistent pieces of equipment they’ve ever made. I know, I use to own one and even on my best day I couldn’t produce a 50pc matched set of brass that was +/- a half thou. Do your self a favor and buy a PMA, K&M, or 21st century powered neck turning setup, it actually makes turning brass somewhat enjoyable.
Dave

 

[Beiruty]

Do not waste your time. Size with no expending ball and use a mandrel from Brownells to expand the neck.

 

[Beiruty]

Trimming all cases to the same length is more important than case neck turning.

 

[hrgriffin1]

The expander mandrel should match the brand of turner you are using. For instance I’m using a K&M expanding mandrel with the K&M neck turning setup. They should be a matched pair. Also +/-.0005” isn’t very tight. My ball mics read down to the hundred thousandths place and there is NO WAY my necks measure over the full range of .001”. That is a lot. Perhaps you meant +/-.00005”
I think turning the inside necks is a waste of time. And honestly most people will tell you that Hornady turning setup is one of the most inconsistent pieces of equipment they’ve ever made. I know, I use to own one and even on my best day I couldn’t produce a 50pc matched set of brass that was +/- a half thou. Do your self a favor and buy a PMA, K&M, or 21st century powered neck turning setup, it actually makes turning brass somewhat enjoyable.
Dave

I am using a ball mic, the Hornady tool is bad if you crank the case holder down which makes it wobble. I tighten it down by pushing down on the back of the case while the neck is on the mandrel. When I do that I actually get zero wobble, and repeatable thickness. When I stated .0005 I wasn’t remembering correctly as I didn’t tale notes so I went back and actually remeasured a few of them. I’m actually getting +\-.0003 on my ball micrometer using the Hornady. Which is pretty amazing considering from the factory I would get variance of a up to couple thousandths. Might not be the best method but I definitely a vast improvement imo.

 

[Scott-ak]

I have fallen down a deep rabbit hole...

yes you have lol

 

[Dave M.]

I am using a ball mic, the Hornady tool is bad if you crank the case holder down which makes it wobble. I tighten it down by pushing down on the back of the case while the neck is on the mandrel. When I do that I actually get zero wobble, and repeatable thickness. When I stated .0005 I wasn’t remembering correctly as I didn’t tale notes so I went back and actually remeasured a few of them. I’m actually getting +\-.0003 on my ball micrometer using the Hornady. Which is pretty amazing considering from the factory I would get variance of a up to couple thousandths. Might not be the best method but I definitely a vast improvement imo.

+/-.0003” is still a tad large for my liking but more than adequate. Honestly I fairly certain that most of my brand new Lapua brass measures +/-.0003” in neck thickness right out of the box.

 

[hrgriffin1]

+/-.0003” is still a tad large for my liking but more than adequate. Honestly I fairly certain that most of my brand new Lapua brass measures +/-.0003” in neck thickness right out of the box.

I currently have an abundance of Lake City brass so I am unable to justify purchasing any Lapua brass. I really would love some .308 Palma brass so I can achieve even better ES/SD than I have already. Once I do then I’ll upgrade my OD neck turning tool.

 

[M-61]

It really boils down to concentricity. If you only turn the outside of the case neck you are only addressing half of the equation. Outside neck turning allows for better concentricity of your brass in the chamber. Inside neck turning allows for better bullet seating concentricity.

You say this as if it’s a fact.
Obviously you can do what you want, and I just noticed you’re not asking a question.
I’ll just say without being asked , the only thing that touches the inside of my case neck is one pass with a nylon brush mainly to insure no media is left there from my vibratory cleaner.

 

[hrgriffin1]

You say this as if it’s a fact.
Obviously you can do what you want, and I just noticed you’re not asking a question.
I’ll just say without being asked , the only thing that touches the inside of my case neck is one pass with a nylon brush mainly to insure no media is left there from my vibratory cleaner.

You’re right, I did state that as if it was a fact. I should have said that’s how my brain perceives benefits of ID/OD neck turning.

 

[Dave M.]

You say this as if it’s a fact.
Obviously you can do what you want, and I just noticed you’re not asking a question.
I’ll just say without being asked , the only thing that touches the inside of my case neck is one pass with a nylon brush mainly to insure no media is left there from my vibratory cleaner.

Precisely what I’ve said many times before. I rarely even put my brass in a vibe bowl (maybe once every 5-6 firings). Nylon brush on the Lyman case prep once in and remove. Done.
Leave that good consistent carbon coating in there.
Dave

 

[Dusty Stevens]

You say this as if it’s a fact.
Obviously you can do what you want, and I just noticed you’re not asking a question.
I’ll just say without being asked , the only thing that touches the inside of my case neck is one pass with a nylon brush mainly to insure no media is left there from my vibratory cleaner.

Wouldnt you think that the finish left by drawing over a mandrel from the factory would be better for a bullet to slide in than any type of machined surface?