Neck turning benefits for factory chambers and brass types?

L

Lange

New member
Hello,

I am new to reloading and wonder about what techniques to get the best accuracy. Am mainly loading for bolt guns right now. Going to try neck sizing and I was wondering if neck turning would be of any benefit. I use all kinds of different brass mainly from fired factory ammo and some LC in .308 and plan to order some Winchester. Loading for 700 5r .308 which I assume is a standard chamber and two other factory 700s. Use standard RCBS FL die sets right now.

Going to try Lee Collet dies for the necks and neck bump. I also have been necking down 30-06 brass to 25-06 for my new 25-06 and I hear necks are thicker but rounds have chambered fine. I'm wondering if neck turning may be a good next step.

Thanks for any insight.
 
Going to try Lee Collet dies for the necks and neck bump. I also have been necking down 30-06 brass to 25-06 for my new 25-06 and I hear necks are thicker but rounds have chambered fine. I'm wondering if neck turning may be a good next step.
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One day reloaders will learn to measure before and again after. Reloaders assume the neck gets thicker because they believe the case is compressed. When a case neck is necked down part of the neck becomes part of the shoulder.

I have formed 30/06 cases to 308W. When finished the neck of the 308W increased in diameter .006” because the neck of the 308 W was formed from the case body of the 30/06 case. There is an advantage when forming 7.62 cases for military chambers. The military chamber is very generous, loose necks can be tightened with 30/06 cases.

F. Guffey
 
I have tried neck resizing with Lee's collet dies in a few different calibers. The improvement in accuracy has been unobservable. I finally stop doing that altogether. It actually generate extra work and expenses.

It didn't replace full length sizer. After a few loads, the brass became hard to chamber. I would have to FL size. So I would need to keep both sizing dies.

The mandrel in the collet die has diameter that barely size down the neck. The sized brass had hardly sufficient bullet grip.

You will do better for accuracy to use full length sizing die with honed neck, so that no expander ball will be needed. Bushing dies will do the same. Both tend to be expensive, and require neck turning.

-TL
 
OP, you may have good results neck sizing only. I second tangolima's posting. I never saw any improvement in accuracy using the Lee collet die.

In my experience, a good full length sizing die will get you good results every time. Forster offers a service where they will hone out the neck of one of their full length sizing dies to your specification, if you wish to go that way. An added benefit of this service is that you get really concentric brass using this die, as you remove the expander ball.

As far as neck turning, unless you have a tight chamber neck, less than .003" clearance, I don't think it is necessary. It might be desirable to turn the necks to make them more uniform, but purchasing good quality brass, such as Lapua, can save you a whole lot of time and aggravation. More importantly, turning brass for a standard chamber will likely not show up on the target as better accuracy.

My $.02
 
I do neck size using the lee collet dies when I can. Cannot confirm any specific increase in accuracy but I've never seen any loss in accuracy using the lee collet neck dies either. "Cases last ten times longer" may or may not apply to your situation. Like others have said a FL die is needed once the neck-sized cases get difficult to chamber. I cannot re-chamber fired LC or Hornady brass in my 308 so that collet die is retired. As far as neck turning goes it's probably more economically sensible to just buy better brass (or specifically to buy 25-06 brass). You might invest $100 just to try neck turning only to find it doesn't make a lick of difference. I know I can find a better use for my $100.
 
Neck turning may or may not help. Testing, only way to know.

Partial neck sizing with collet die

Posted by on 20 October 2011 07:50 AM


If you want to resize just a part of the neck, find a washer at your local hardware store the has an inner diameter large enough to fit over the case, and an outer diameter large enough so that it contacts the collet sleeve that protrudes from the bottom of the die. Slide this washer over the case after the case has been inserted into the shell plate. Now when the ram is raised, you can still close the collet by applying force at the top of the stroke, but the case will not go up as far into the collet, and the neck will be sized less an amount equal to the thickness of the washer.
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The unsized part helps alignment in the chamber, with Redding Bushing dies. Dont use Lee. http://leeprecision.net/support/index.php?/Knowledgebase/Article/View/137/73/partial-neck-sizing-with-collet-die
 
I used to spend a lot of time prepping cases, part of which was turning necks. It's a lot of tedious work, so I just changed over to Norma, Lapua, and Nosler and don't prep them at all. I do run them through a Lee Collet Die and trim them prior to loading. The Lee die eliminates run-out.

My resizing, after many years of trying this or that, is now done with a Lee Collet Die for Calibers with light to medium loads. Calibers with max loads, the cases are resized with FL dies set to bump the shoulder back a desired amount. You can't go wrong with just using a FL die as I do.

I have a lot of standard type neck sizing dies to sell. I just don't use them any longer.

If necking down cases, you might want to measure neck wall thicknesses and turn necks if necessary. The neck wall thickness has to be thin enough to 'release' the bullet when fired. I ran into a problem with a new barrel that had a tight match chamber. If the OP has a roomy factory chamber, he's probably Ok, but I'd still measure neck wall thickness of necked down cases.
 
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Anything, everything you can do to maintain a high degree of concentricity (low runout) in your loaded ammo will bear fruit with improved accuracy. Neck turning is one of those things. Get a concentricity gage and figure out where you are introducing runout.
 
Lange
Going to try Lee Collet dies for the necks and neck bump. I also have been necking down 30-06 brass to 25-06 for my new 25-06 and I hear necks are thicker but rounds have chambered fine. I'm wondering if neck turning may be a good next step.
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I have yet to use my 25-05 reamer and dies, but I have lots of experience with 257 Roberts Ackley improved , 257 Roberts Ackley improved rimmed, 260, and 243.

I can size WIN or RP 8x57 brass down to 257 Roberts, seat a bullet, and chamber a round without interference.

But I cannot size down Norma 7x57R brass to 257 Roberts, seat a bullet and without getting 0.003" interference. I have to turn the neck. See pic

That was unexpected.

Sizing Win and RP 308 brass down to 260 will fit 90% of the time.
The other 90% of the time there is ~~0.001" clearance of the cartridge neck in the chamber neck.
But I cannot size Lapua 308 Palma down to 260, seat a bullet and chamber a round. I must turn the necks. That was unexpected too.

When I size down 30-06 brass to 6.5-06 A Square, that works.
But when I size down 270 brass to 6.5-06 A Square, the brass is too long, and need to trim length. That was unexpected.

If I size down 308 to 243, load to what I think is only 10% over 65kpsi, force the bolt closed on a pinched neck, the primer pocket can double in diameter, the case is stuck, and I have to pound open the bolt, and pound out the case with a cleaning rod. That was unexpected. It is better to read about pinched necks overpressure than to experience it. I did that 15 years ago and have not done it since.

What does it all mean?
1) Some brands of brass have thicker necks and can be necked down less before turning is required.
2) Some necking down is so close to fitting that some cases will be problems. It is a percentage yield problem.
3) Some cases can be too long when necked down and need trimming for length. An over long case can pinch a bullet too.
4) Pinched bullet over pressure caused by thick case necks can make a real mess.
 

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I`ve read some good points to ponder...while I have never neck turned the outside of a case, I have reamed the inside...I bought a new 700 BDL in 7mm08 back in 1980 or `81...factory ammo was scarce in this new cal. since I had plenty of LC MATCH brass on hand, I used that to form to 7mm...the necks were thicker on most of the cases so I purchased an inside neck reamer from Forester...I had to ream the necks before fl sizing to 7mm08...the forester reamer is simply a fluted pilot for their standard trimmer...I still use it occasionally on my .308 brass for the bolt gun and the M1A.

I do check all my fired brass in .308 with a 168 sierra bthp. just stick the nose of the bullet in the mouth of a fired case and you can see instantly if you have a neck that needs to be reamed...It will fall right in...if the neck is too thick the bullet wont fit at all by hand. Do this check before sizing...set the thick ones aside till you have a batch to ream all at once. just as a side note, I have never neck sized anything...I only FL size...I may go through more brass, but fl sizing will eliminate chambering problems. just as brass flows forward on each firing, causing the need to trim their length, the necks also thicken and eventually will need reaming inside or turning outside, to eliminate a too tight fit.
 
It's odd that everyone says that as cases are used the brass flows forward and thickens the necks. It actually makes sense. But...way back when, I partial resized some Norma cases many many times. I couldn't guess how many times. I knew how to reload, but there was a lot I didn't know. So, one day I decided to neck size the cases. I did that, primed the cases, filled with powder, and when I went to seat the bullets, they fell into the case. The necks had thinned over time. Hot loads in a 220 Swift. Shot em, partial sized em, trimmed em, again and again and the necks thinned.
 
Thanks for all the input and advice. I think ill give neck sizing with Lee Collet a shot, probably no neck turning right now. Going to be working with Winchester brass for the .308. Trying to find the node right now for my 168 gr Hornady loads with Varget. Gotta be somewhere between 42-44 grains I take it.
 
Clark,
When I size down 30-06 brass to 6.5-06 A Square, that works.
But when I size down 270 brass to 6.5-06 A Square, the brass is too long, and need to trim length. That was unexpected.
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That shouldn't be unexpected, the 270 win is based on the longer 30-03 brass, not the 30-06 brass, it would be unexpected if you didn't have to trim.

Just a reminder to all of use when necking down to always check for clearance to be safe.

Jimro
 
To the OP...when using the Lee Collet die, if it isn't set up properly or isn't working smoothly, you can collapse the case shoulder just a teeny bit. You can't tell by looking. The case, empty or loaded, won't chamber. While resizing necks, run an occasional case through the action to make sure all is working properly.

If you do have that chambering problem with a loaded round, a Redding Body Die will solve the problem. If you catch it before you load it up, just run it through your FL die.

Then disassemble the Lee die and lube it a tiny bit.
 
On a factory barrel neck turning may not be necessary. Your Rem. 5R barrel is a nice barrel probably a 1-12 twist . Check your fired case neck measurement and add.001 to your case measurement, that is very close to your chamber neck. On a custom barrel the chambers are cut so tight, doesn't leave much space to expand for the neck. That's when neck turning is a must. With your loads I would bet F/L sizing to .001 headspace with the expander ball would give you the most accurate loads trouble free, .001 runout. Give it a try & see. Hope I helped.
 
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Jimro
That shouldn't be unexpected, the 270 win is based on the longer 30-03 brass, not the 30-06 brass, it would be unexpected if you didn't have to trim.

Just a reminder to all of use when necking down to always check for clearance to be safe.

Jimro
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I have been married for 38 years. 38 years ago we had a book on planning your wedding. In there it said not to worry too much about things going wrong, because soon the only things you will remember about the wedding is what went wrong.
That was not entirely true, but the mistakes do seem to have extra weight in the memory.

My guess is that if you read this whole thread, wait a few days, all you will remember is Clark screwed up with long 270 brass in his short 6.5-06 A Square chamber.
 
Jimro
That shouldn't be unexpected, the 270 win is based on the longer 30-03 brass, not the 30-06 brass, it would be unexpected if you didn't have to trim.

Just a reminder to all of use when necking down to always check for clearance to be safe.

Jimro
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I have a better reminder, purchase reloading manuals and then; read them. I suggest becoming familiar with SAAMI specs and I am the fan of measuring before and again after. The 270 Winchester case is .041” longer than the 30/06 case; my opinion? That is nice. When necking a case down the neck gets longer: I understand, reloaders believe the neck gets thicker. My problem; I can make reloaders mad but making them think is more difficult.

When going from 270 to 25/06 the case neck gets shorter and the shoulder gets longer between the two junctures, part of the neck of the 270 becomes part of the shoulder of the 25/06.

Point? Measuring the length of the case before necking up and or down and again after necking up and or down is SOP; Standard Operating Procedure. My favorit3e case is the 280 Remington. The 280 Remington case is .051” longer from the shoulder of the case to the case head than the 30/06 case. The questions should be about what to do with all that extra length between the shoulder and case head?

F. Guffey
 
My guess is that if you read this whole thread, wait a few days, all you will remember is Clark screwed up with long 270 brass in his short 6.5-06 A Square chamber.
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I hope I remember more to always check my reformed brass for neck interference after sizing and trimming.

I had some range pickup 270 brass that I necked up to 30-06, needed trimming. Used them for feeding a Garand. Necked up a bunch of 243 Win to 308 Win too, made good accuracy loads when I couldn't get Winchester brand brass to save my life. I never bothered to check neck dimensions when necking up, just trim to length and load, seemed reasonable at the time anyways.

Jimro
 
I have outside turned necks, its a lot of work and looks pretty. It looksfunny on nickel cases. I do not think it helps much unless you are a benchrest shooter. Case necks are not consistant thickness all the way around. I don't know how much it actually affects accuracy.

Using a lee collet die for my 7 mm mag, I polished the mandril until I had the desired bullet pull. This was suggested by Mr Lee. That rifle shot great. Its the only rifle I ever shot out.

David

Sent from my SM-T900 using Tapatalk
 
My results have been a little different than most of those discussed. I started with turning the necks on Winchester 270 Win cases and neck sized with Redding dies. Probably reduced the average group by 1/4". When I need to FL resize cases, I use the Forester FL die because they do not reduce cases to industry minimums. To bump the shoulders, I use the Forester bump die. My practice is now the same with all calibers except 338 Lapua...because Forester doesn't make a bump die for it yet. I have also learned that neck turning for hunting guns is a waste of time if you are using Nosler, Lapua or Norma cases. One mans humble opinion.
 
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