Full length sizing vs neck sizing?

mr_magicfingers

Well-Known Member
More reading of reloading manuals raises more questions. I understand that full length resizing of cases is necessary when you take brass fired in another gun to bring it back to specification. However, if you are using brass fired from your own gun for reloading, I understand this to be 'fire formed' to your own chamber. Is there a reason to full length resize this brass or would you normally just neck resize?

Thanks.
 

LeftHandGuy

Well-Known Member
Neck sizing should in-theory give you greater accuracy - and doesn't require case lubrication. If you use the brass enough though, I have been warned it will need FL resizing eventually.

You can reload pretty well with a fairly cheap Lee Loader which only neck sizes. That's how I load and my ammunition seems to work fine (after going through some teething problems caused by my own ignorance).
 

stecad

Well-Known Member
Neck sizing is generally seen as the preferred way to go as it prolongs the life of the brass and does improve accuracy. It is easier and quicker for reloading and avoids (or should do) the risk of a stuck case (always a chance with FL sizing).
As with most rules in life there's always exceptions.
I have 2 308s (Sauer & Steyr) and as long as I keep the brass separate can get away with just neck sizing. The Sauer will use any once fired brass if I neck size it but the Steyr always needs a FL then I can get away with neck only.
My 243 on the other hand has to be FL every time as the neck needs to be bumped back a touch otherwise the round is tight as hell to cam the bolt in.
If you can get away with NS only then go for it.
 

jcampbellsmith

Well-Known Member
More reading of reloading manuals raises more questions. I understand that full length resizing of cases is necessary when you take brass fired in another gun to bring it back to specification. However, if you are using brass fired from your own gun for reloading, I understand this to be 'fire formed' to your own chamber. Is there a reason to full length resize this brass or would you normally just neck resize?

Thanks.
Full length resizing every time is the way to go. Myths abound about neck sizing. Ignore them and respect your quarry and rifle. Regards JCS
 

PeterH

Well-Known Member
My 243 on the other hand has to be FL every time as the neck needs to be bumped back a touch otherwise the round is tight as hell to cam the bolt in.
If you can get away with NS only then go for it.
Shoulder
 

jonylandrover

Well-Known Member
Neck sizing will help brass last longer, less stress on the case over its full length. Its also faster and easier on your press.

James
 

old keeper

Well-Known Member
Like most queries regarding reloading there never seems to be a definitive answer, very confusing for those wishing to learn!
 

Woodsmoke

Well-Known Member
I posed this very question only a week or back & the general consensus was that the advantages to be had from neck-sizing only were minimal fro the average shooter. I intend to full-length resize & be done with it. I think it was Muir who mentioned that too much thinking would just scramble your brain & it was easiest just to keep things simple. Good advice that I for one intend to stick to ;)
 

foxyloxy

Well-Known Member
I found that I was getting inconsistent neck tension with neck sizing, so I FL size all my brass now.
 

Yorric

Well-Known Member
Hi K --- with your neck bushings do you need to neck turn? Or do you just select the optimum bush to only just reduce the neck outside diameter by a minimal amount? Also is the actual final neck sizing still done with a mandrel?

Ian
 

Muir

Well-Known Member
I seldom neck size any more. It has to be a special situation to warrant it. Now I FL resize almost everything including my varmint rounds for .223, 204, and 222: They are very accurate. FWIW, there have been several studies lately that show no advantage in neck sizing. Lyman's new #49 manual comes to mind. They no longer recommend it.~Muir
 

Klenchblaize

Well-Known Member
I think there is or at least could be a little confusion here:

1. A standard FL sizing die will neck size in the process of FL resizing a case if setup so. (That’s what its designed to do so the bullet is held in place!)
2. A standard FL sizing die cannot neck size only but rather - and at best - partial neck size in accordance with how backed off the die is. (Its easy to spot this approach on a loaded round.)
3. The only way to full length neck size only is c/o a neck only sizing dye be it one that accommodates bushings or, as I’ve seen, a standard FL die is reamed out to permit contact with the neck only when set down on the shell holder as per FLS setup.

Phew!

K
 

jcampbellsmith

Well-Known Member
Hi K --- with your neck bushings do you need to neck turn? Or do you just select the optimum bush to only just reduce the neck outside diameter by a minimal amount? Also is the actual final neck sizing still done with a mandrel?

Ian
Ian.

I've tried a number of approaches with the Redding 'S' type full length resizing die and bought a lot of bushings. Resized with both the expander ball removed and the expander ball in place. Also expanded with a standalone mandrel.

My current practice is just to use a Forster full length resizing die. One operation, little thought and good results. Also have ditched the Remington brass and focus on Lapua, Nosler and Norma brass as appropriate for the calibres I'm shooting.

Regards

JCS
 

enfieldspares

Well-Known Member
You can neck size using the standard FL sizer if you go about it this way. Take a fired case and black the shoulder of the neck AND THE NECK with soot from a candle. Now put the FL sizing die in your press and screw it down as normal for your usual full length sizing operation.

Now back it off by turning back two full turns. Then run a fired case through the press and see where the soot is removed from. You are trying to scrape ALL the soot off the neck but just "touch" it on the shoulder. Such that it goes from a matte just smoked on to a very, very, very, gently pressed down appearance. So keep running the case up and down and screwing the die down towards the shell holder until this effect is seen.

Now run the case back up a final time, adjust nothing, just simply lock the die with your lock ring.

Congratulations. You are now neck sizing by using a standard FL sizing die.

Personally I don't bother and follow what MUIR says. The only exception I ever made to this was in RIMMED rifle cartridges like our venerable British 303 where in "long" chambered cases it prolonged case life by making the round effectively headspace NOT off the rim as designed but off the shoulder. And that was a real benefit in that calibre.
 
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swarovski

Well-Known Member
I thought neck sizing is only benefited if the case gets put in the chamber exactly the same as it was fired the previous time,if not there is no point and fl size,hear say :D
 

NigelM

Well-Known Member
I don't know if i'm "right" or "wrong", but I only use Norma or Lapua brass, FL size on new cases and then neck size after that.

My logic is that once fire formed brass is the perfect size for YOUR chamber. It does not need to be made a few thou smaller only to be expanded again. The neck on the other hand is smaller than the chamber to grip the bullet and is allowed to expand a few thou to let the bullet out. This bit has to be resized.

Less movement/manipulation of brass must mean better accuracy and a longer life, less molecular movement on each firing.

Now as I said, I don't know if my theory is "right" "or wrong", but all my guns (6mm06AI (brutal on brass), 6.5 Lapua and 6-6.5 Lapua) shoot inside .5 MOA and I get 5 to 6 reloads from the 6mm06AI and 7 to 8 out of the Lapuas.

It works for me. Even if I'm "wrong" I'm not planning on changing what I do.
 

deeangeo

Well-Known Member
Setting up the FL die correctly so that it just bumps the shoulder is the key
It certainly is the key...and to do that, you need to know the exact headspace dimension taken from both the fired & de-primed cartridges and the measurement from mid case shoulder to boltface (assuming a rimless case). Only after determining these two dimensions and utilising from the compared dimensions a die setting to work to, can you set your f/l sizing die so as to resize either to that exact dimension with a tolerance of absolute max: +/- .001"

But the benefit of doing the above absolutely delivers much greater consistency, extends brass life enormously (especially if annealing cases each 3-4 firings is done) and is guaranteed to function every time in your action.

Of course, there are also other aspects of setting up the f/l die so that case neck/case concentricity is achieved together with bullet seating technique to also maintain concentricity of the finished round. Doing all of the above correctly removes any requirement for neck sizing, which following several firings would require a f/l resizing anyway.
ATB
 

Yorric

Well-Known Member
Ian.

I've tried a number of approaches with the Redding 'S' type full length resizing die and bought a lot of bushings. Resized with both the expander ball removed and the expander ball in place. Also expanded with a standalone mandrel.

My current practice is just to use a Forster full length resizing die. One operation, little thought and good results. Also have ditched the Remington brass and focus on Lapua, Nosler and Norma brass as appropriate for the calibres I'm shooting.

Regards

JCS
Hi JCS -
I use Lee FL & collet neck sizer dies for all the chamberings I have & usually currently do a simple FL single op sizing, not bothering with the neck sizing at the moment due to rifle swaps & a re-barrelling currently ongoing.
This way I know that I won't have any chambering problems.
Nowadays all my rifles have good tight minimum tolerance chamber dimensions & they don't allow much permanent case deformation, so FL sizing doesn't move the metal too much.
I also have a 223 RCBS FL sizer to play with, & can't measure any improvement over the Lee option in use.
I see no need to go to the expense of expensive dies with expensive bushings - certainly as all my rifles are shooting well enough as they are.
I get adequate case life as I anneal after every couple of re-size cycles. Set up right the dies produce perfectly adequate quality ammo for my requirements.
I use various makes of case & have not yet proved to myself with clear evidence that one is truly better than another. - I think that the annealing really helps in this direction.
I think that the die mandrel size & surface finish quality is the real key & also the cleanliness of the case neck inside diameter a close second. --- The stainless wet pin polishing really helps to optimize this. - Dirty, oxydized or fouled surfaces in the necks is not going to help with either consistency or mandrel life so I always wet polish every loading.


Ian
 

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