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to full length re size or not?

jeep505090

Private
Full Member
Minuteman
Oct 12, 2009
89
0
New York
im getting ready to get a set of dies for .308 im hearing two different approachs in sizing, full length re-size or only neck size? what is the better way or is it preference and if there is a prefered way can someone explain it in simple mans terms? tango.
 
Re: to full length re size or not?

I always heard to full length size brass if you want to make sure the round will feed. If shooting matches. Some will neck size only but after so many times of that. I heard you will have to full length size them anyway.
So why not just full length size them all the time.
 
Re: to full length re size or not?

Full length sizing crushes the brass down smaller than your chamber, then firing stretches it back out. The repeated action stresses the metal.

You only want to form the cases small enough to guarantee chambering.

If you could choose only one, then it needs to be FL sizing. If you have a bolt rifle, then you can neck size until the rounds are hard to chamber then FL size them.

OR

you can setup your FL sizing die to only resize the case enough to reliably chamber by bumping the shoulder back a couple thousanths. I have not used this method before, but I plan to.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Victor N TN</div><div class="ubbcode-body">If you're crushing the brass, you don't have the sizing die set right.</div></div>

Crushing was probably not the best description, but it's all I had at the moment. I am fully able to set my die, just not my brain at the time I was posting.
 
Re: to full length re size or not?

I use a F/L die, but usually it's backed off so it doesn't resize more than the final 1/16" or so of the neck.

My loads tend to be on the milder side, and I find that case walls and shoulders don't grow very much, and that once the case walls are expanded after one or two firings, the radial growth usually stops. The kind of brass working that leads to case head separation simply doesn't get done except when a bump is needed.

I test my resized cases for chambering, and if there's excessive resistance, I reset the die to resize full length, and resize the lot. If there's still resistance, the case length needs trimming, and they all get trimmed to the same length.

Greg
 
Re: to full length re size or not?

My reloading is designed for good but not best-possible accuracy and longest possible brass life. If you make the tradeoff the other direction, Full Length size.

I run all myy cases through a case micrometer to determine if the sholder remains short enough to NeckOnly size the case and use this to sort the cases into FL size and NO size steps.

In the FL size lot, I size only as much as needed (0.002) so that the case is worked as little as possible. I do this with a body die.

In the Neck sizing step, I first use a 0.338 bushing to reduce the obturated neck from 0.3445 and then in a second operation from 0.338 with a 0.332 bushing.
 
Re: to full length re size or not?

After conducting the Neck Sizing/Full Length Sizing routine for 3 cycles on 150 pieces of brass I switched to full length only. It just made more sense to me. I strive for consistency and neck sizing does not deliver that. It felt like I was working backward. I FL size with minimum shoulder bump. I also run a relativity light load and anneal all my brass (in cycle) at the same number of cycles. I decide to anneal when I feel a marked increase in resistance to sizing. You will know when you get to that point and annealing is easy. I have 7 cycles on 150 pieces of winchester brass in .308 with zero neck splits or case head separations. I have only annealed the whole batch once. I shoot 168grs SMK's over 43.5grs of Varget fired by Fed 210 primers in my 700p.

I think FL sizing will do you good.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">Full length sizing crushes the brass down smaller than your chamber, then firing stretches it back out. The repeated action stresses the metal.

You only want to form the cases small enough to guarantee chambering.

If you could choose only one, then it needs to be FL sizing. If you have a bolt rifle, then you can neck size until the rounds are hard to chamber then FL size them.

OR

you can setup your FL sizing die to only resize the case enough to reliably chamber by bumping the shoulder back a couple thousanths. I have not used this method before, but I plan to. </div></div>
Lone Wolf is on the money. However one small point . For a bolt gun. When you talk about Full Length sizing dies you are talking about sizing the neck and the case body at the same time. This will not be very good for partial sizing and just bumping the shoulder as the neck of the case gets stretcheda bit on the way out of this kind of die. Requiring extra sizing to start with so it comes out the right size. For shoulder bumping with good control and no ne ck stretching you usea Body die not a FL die.
That way the neck sizing is totally seperate from the body sizing .
You only neck size for as many shots as it takes to start getting sticky cases and then you neck size first then give them a run into the body die just enough to neatly get them back in the chamber. Then only neck size until they get sticky again. No excessive oversizing is done so concentricity of the fireformed case is maintained. Therefore accuracy is maintained.
For an Auto gun you will have to have a looser cases fit to assure reliable cycling of the action.
 
Re: to full length re size or not?

Get the rifle with a minimum chamber and then F/L allways. The brass will not get hurt as the F/L sizing will not really move that much brass anyway.

With a max sized factory chmaber you might be able to get better accuracy with neck sizing but then you might have sometimes hard to chamber ammo and/or brass extraction problems.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LoneWolfUSMC</div><div class="ubbcode-body">Full length sizing crushes the brass down smaller than your chamber, then firing stretches it back out. The repeated action stresses the metal.

You only want to form the cases small enough to guarantee chambering.

If you could choose only one, then it needs to be FL sizing. If you have a bolt rifle, then you can neck size until the rounds are hard to chamber then FL size them.

OR

you can setup your FL sizing die to only resize the case enough to reliably chamber by bumping the shoulder back a couple thousanths. I have not used this method before, but I plan to. </div></div>
When you talk about Full Length sizing dies you are talking about sizing the neck and the case body at the same time. This will not be very good for partial sizing and just bumping the shoulder as the neck of the case gets stretcheda bit on the way out of this kind of die. Requiring extra sizing to start with so it comes out the right size. For shoulder bumping with good control and no ne ck stretching you usea Body die not a FL die.
That way the neck sizing is totally seperate from the body sizing .
You only neck size for as many shots as it takes to start getting sticky cases and then you neck size first then give them a run into the body die just enough to neatly get them back in the chamber. Then only neck size until they get sticky again. No excessive oversizing is done so concentricity of the fireformed case is maintained. Therefore accuracy is maintained.
For an Auto gun you will have to have a looser cases fit to assure reliable cycling of the action. </div></div>


How is fl sizing streching the neck compared to nk sizing?, If your using the same style of die??

Do you batch your brass? If one needs a shoulder bump do you bump your whole batch of brass? If you don't you just changed the case volume on one case compared to the others in the batch.
 
Re: to full length re size or not?

My chambers are always SAAMI spec. This makes things like neck turning and precise bushing neck sizing somewhat superfluous. It also frees me from being unable to process 'standard' ammunition in my firearms.

I know this means sacrificing some accuracy, but I also find that such sacrifice becomes more or less lost in the background noise of other uncontrollable factors, as long as I am serious about maintaining markmanship basics.

I believe that an average marksman will default a degree of marksmanship error that often negates much/most of the painstaking effort many of use invest into our ammunition fabrication process.

Very few of us, myself included, are as much 'on the ball', as much of the time, as we'd like to think. There's good reason why people like G. David Tubb are Champions, and I'm not. They have far better self discipline.

While it's true that a great marksman can't shoot bugholes with less than stellar ammo; it's equally true that average marksmanship will seldom render better than average acccuracy, no matter what the quality of the ammo.

Dependence on luck is not part of the basics.

I pay close attenton to brass prep, and things like individually weighed propellant charges, but I have found that for me, and maybe many like me, there is a point of diminishing returns where painstaking ammo fabrication is involved; and that this point falls rather further short of where many of us believe our marksmanship warrants than many of us are willing to admit. What I do, I endeavor to do consistently, and beyond that I try to keep my obsessions on a short rein.

That's neither an indictment nor a criticism, but simply an admission that I'm willing to settle for a more realistic appreciation of my own capacities. Maybe I'm alone in this, maybe I'm not.

Greg
 
Re: to full length re size or not?

First off a FL die ( standard Full length die) is not the same style of die compared toa neck size only.
When you size in a standard FL die as you extract the case the die holds onto the necck with greater grip than a neck size only die generaly speaking. Some standard neck dies with expander balls will also stretch the neck and shoulder if the brass is thick or the die extra tight. However at least with the neck size only die you can reduce the length of the neck that is sized , reducing the potential problem.
With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die.
 
Re: to full length re size or not?

" Very few of us, myself included, are as much 'on the ball', as much of the time, as we'd like to think. There's good reason why people like G. David Tubb are Champions, and I'm not. They have far better self discipline."

David Tubb is a champion because he is blessed woth outstanding eyesight and rock steady muscles and nerves.
He does not suffer as much stress and nerves as other people do.
His handloading ability is no better than most.
God blessed him with just the right talents to be a great shot.
I have seen a natural shot myself. It was a cousin of mine from England. He had never fired a GUN ever in his life.
I took him target shooting and within a few minuets he was producing tight groups. With a handgun he was better than me straight away. He went back to England and joined the Police force and got the highest scores with a handgun that they had ever seen in recruit training.
You can't teach that . It is a freak of nature.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">" Very few of us, myself included, are as much 'on the ball', as much of the time, as we'd like to think. There's good reason why people like G. David Tubb are Champions, and I'm not. They have far better self discipline."

David Tubb is a champion because he is blessed woth outstanding eyesight and rock steady muscles and nerves.
He does not suffer as much stress and nerves as other people do.
His handloading ability is no better than most.
God blessed him with just the right talents to be a great shot.
I have seen a natural shot myself. It was a cousin of mine from England. He had never fired a GUN ever in his life.
I took him target shooting and within a few minuets he was producing tight groups. With a handgun he was better than me straight away. He went back to England and joined the Police force and got the highest scores with a handgun that they had ever seen in recruit training.
You can't teach that . It is a freak of nature.

</div></div>

I totally agree with your assessment. In just about all walks of life, some people are just naturals. Carlos Hathcock is another example. You just can't teach someone to shoot like he did. I guess its just instinctive.
 
Re: to full length re size or not?

Well, folks; if you think my point was that G. David Tubb is a champion and I'm not, I guess that's OK. But what I was trying to convey was that it pays to perform specific detail tasks on brass, etc., based on actually observed benefits. That's what I've done and I find that many of the frills are just that, more work than actual benefit justifies.

BTW, I've asked Mr. Tubb about F/L resizing and he told me he F/L resizes every time.

Greg
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">
I have seen a natural shot myself. It was a cousin of mine from England. He had never fired a GUN ever in his life.
I took him target shooting and within a few minuets he was producing tight groups. With a handgun he was better than me straight away. He went back to England and joined the Police force and got the highest scores with a handgun that they had ever seen in recruit training.
You can't teach that . It is a freak of nature.

</div></div>

Sorry Country going to have to call you on this one.

COMPLETE and UTTER BULLSHIT!!

There is NO handgun training in so called "recruit training". Actually it's called 'police training' and I have been through it.

You MIGHT get to see a firearm, but that's as far as it goes. The instructors tell you that "Guns are BAD. Call for help and get TFU on the case" TFU by the way stands for 'Tactical Firearms Unit' and it's what we call our armed officers, as BRITISH POLICE OFFICERS ARE NOT ROUTINELY ARMED"

Please don't get into a pissing contest over this, like you did with Nobody.

Accept the call and move on.

SORRY GUYS. I didn't want to go off thread, but I just couldn't let this gross bollocks pass unmentioned.

Speaking of my hero,

"CONSIDER THE SOURCE"

Lonewolf, Greg and Victor are GTG and the OP should listen to them.

Thanks Guys,

N
 
Re: to full length re size or not?

I too have both for my 300WM, which is the only calibre that I neck size.

All others I fl size.

We recently had a reloading talk at my club by one of our leading lights who shoots 1000yd benchrest as well as F class. He has recently gone back to FL resizing, after trying all the other methods. It seems that this is the trend in benchrest/F-class in the UK at the moment.

It may well have much to recommend it as he came 2nd at a comp at Diggle (North west England - VERY windy, cold, very challenging weather conditions) while developing his loads. He beat all but one of the British team.

Way to go Simon!

N
 
Re: to full length re size or not?

I did F/L size until I had a FTF with my PGWDTI Coyote and have since started SB sizing. I haven't looked back.

FWIW I don't care about brass life and I'm using once fired Norma, but I'm at the 8th reloading on a batch and there appear to be no signs of failure at this time.
 
Re: to full length re size or not?

I have discontinued using .308 in favor of the .260Rem, and now I regret having given away my .308 reloading dies. Some thought suggests that the .308 F/L resizing die, with the decapper stem removed, might make a pretty good bump die for the .260 cases. Likewise maybe the .338 Fed or .358 Win for the .308; and maybe a .35 Whelen for the .30-'06, etc...

Just trying to think creatively without having to resort to specialty dies...

Having once trusted Remington brass to be properly to spec once and then having to withdraw from a pretty important match because the unresized new brass wouldn't chamber in my 'loaded' M1A, I now F/L resize all my brass before using it the first time.

Since I make my .260 Brass from Win .243 or 7-08 brass, F/L resizing is a standard step anyway. Pleasantly, the process is no different from F/L resizing new Rem .260 brass; just size and go. For the .243's it helps to lube inside the case nacks, but it's not absolutely essential, and the brass that's not lubed functions the same as that which was.

Greg
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">First off a FL die ( standard Full length die) is not the same style of die compared toa neck size only.
When you size in a standard FL die as you extract the case the die holds onto the necck with greater grip than a neck size only die generaly speaking. Some standard neck dies with expander balls will also stretch the neck and shoulder if the brass is thick or the die extra tight. However at least with the neck size only die you can reduce the length of the neck that is sized , reducing the potential problem.
With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die. </div></div>

If you use the same bushing in a neck or FL die it grips the neck the same, no way aroud it. Or running the same size expander ball through the neck is giong to pull the same the die doesn't matter. If you want to partial size the neck go for it but I'll pass on that, just another variable unless your going to trim to length every time.

"With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die."

If you cant maintain headspace with a fl die your giong to have problems with a body die also, they size the same way minus sizing the neck.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">I have discontinued using .308 in favor of the .260Rem, and now I regret having given away my .308 reloading dies. Some thought suggests that the .308 F/L resizing die, with the decapper stem removed, might make a pretty good bump die for the .260 cases. Likewise maybe the .338 Fed or .358 Win for the .308; and maybe a .35 Whelen for the .30-'06, etc...

Just trying to think creatively without having to resort to specialty dies...

Having once trusted Remington brass to be properly to spec once and then having to withdraw from a pretty important match because the unresized new brass wouldn't chamber in my 'loaded' M1A, I now F/L resize all my brass before using it the first time.

Since I make my .260 Brass from Win .243 or 7-08 brass, F/L resizing is a standard step anyway. Pleasantly, the process is no different from F/L resizing new Rem .260 brass; just size and go. For the .243's it helps to lube inside the case nacks, but it's not absolutely essential, and the brass that's not lubed functions the same as that which was.

Greg </div></div>

Greg, forester is now again making there neck and shoulder bump dies as not special order. I think there around 40 bucks.
 
Re: to full length re size or not?

For new brass I use Winchester. Sometimes the stockboys give it a beating. I neck size all of it prior to loading to take out the case mout dings.

I don't compete with new brass. It's all at least once fired. That way I have to really screw something up before it won't chamber.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Paduan Learner</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">
I have seen a natural shot myself. It was a cousin of mine from England. He had never fired a GUN ever in his life.
I took him target shooting and within a few minuets he was producing tight groups. With a handgun he was better than me straight away. He went back to England and joined the Police force and got the highest scores with a handgun that they had ever seen in recruit training.
You can't teach that . It is a freak of nature.

</div></div>

Sorry Country going to have to call you on this one.

COMPLETE and UTTER BULLSHIT!!

There is NO handgun training in so called "recruit training". Actually it's called 'police training' and I have been through it.

You MIGHT get to see a firearm, but that's as far as it goes. The instructors tell you that "Guns are BAD. Call for help and get TFU on the case" TFU by the way stands for 'Tactical Firearms Unit' and it's what we call our armed officers, as BRITISH POLICE OFFICERS ARE NOT ROUTINELY ARMED"

Please don't get into a pissing contest over this, like you did with Nobody.

Accept the call and move on.

SORRY GUYS. I didn't want to go off thread, but I just couldn't let this gross bollocks pass unmentioned.

Speaking of my hero,

"CONSIDER THE SOURCE"

Lonewolf, Greg and Victor are GTG and the OP should listen to them.

Thanks Guys,

N </div></div>
If you think you can say I'm bullshit when talking about my own cousin and I will not come back at you then you are very mistaken .
I you bothered to read my post properly . I said NOTHING about handgun training at ALL .
I said "In recruit training " period.
THEY DO HAVE RECRUIT TRAINING EVEN IN ENGLAND!!!
I don't LIVE in England so what part of the training is gun handling and what is not I would not have a clue but I know he toped his target shooting.
Police in England do carry firearms at times hell you can see that in the news . So you are saying that nobody in the English Police is qualified to use a gun unless they are in the SWAT team . I think you are the bullshit artist .
It should be obvious to anyone that you are nursing a grudge about MR Nobody .
Why? He was the rudest ,racist , most aggressive and abusive member on this or anyother forum I have been on.
Why would you want to associate yourself with that or anyone like that ?

I have made a life study of many of the great shots and snipers of the past back to the civil war and what I said was completely accurate and in no way a put down of the great Mr Tubb . All CHAMPIONS HAVE A SPECIAL GOD GIVEN TALENT TO BE GOOD AT WHAT THEY DO THEN TRAINING AND DISCIPLINE MAKES THEM EVEN BETTER.

You started a pissing contest sport.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C.K</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">First off a FL die ( standard Full length die) is not the same style of die compared toa neck size only.
When you size in a standard FL die as you extract the case the die holds onto the necck with greater grip than a neck size only die generaly speaking. Some standard neck dies with expander balls will also stretch the neck and shoulder if the brass is thick or the die extra tight. However at least with the neck size only die you can reduce the length of the neck that is sized , reducing the potential problem.
With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die. </div></div>

If you use the same bushing in a neck or FL die it grips the neck the same, no way aroud it. Or running the same size expander ball through the neck is giong to pull the same the die doesn't matter. If you want to partial size the neck go for it but I'll pass on that, just another variable unless your going to trim to length every time.

"With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die."

If you cant maintain headspace with a fl die your giong to have problems with a body die also, they size the same way minus sizing the neck. </div></div>
I was not talking about a bushing type die.
There is no way that you can bump the shoulder with A STANDARD FULL LENGTH SIZING DIE as accurately as you can with a BODY DIE.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Greg Langelius *</div><div class="ubbcode-body">Well, folks; if you think my point was that G. David Tubb is a champion and I'm not, I guess that's OK. But what I was trying to convey was that it pays to perform specific detail tasks on brass, etc., based on actually observed benefits. That's what I've done and I find that many of the frills are just that, more work than actual benefit justifies.

BTW, I've asked Mr. Tubb about F/L resizing and he told me he F/L resizes every time.

Greg </div></div>
No we don't think that is your point at all. What I said was to let you know NOT TO BEAT YOURSELF UP BECAUSE YOU ARE NOT A CHAMPION LIKE G. DAVID TUBB . Champions are born not trained . Training only makes them better at it.
Thats all I ment to convey .
Do you realise that right now in this thread there could be as many as 4 different ideas of what constitutes an F/L die!!!

Jesus this has to be the hardest forum to please on the net bar Benchrest Central .
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C.K</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">First off a FL die ( standard Full length die) is not the same style of die compared toa neck size only.
When you size in a standard FL die as you extract the case the die holds onto the necck with greater grip than a neck size only die generaly speaking. Some standard neck dies with expander balls will also stretch the neck and shoulder if the brass is thick or the die extra tight. However at least with the neck size only die you can reduce the length of the neck that is sized , reducing the potential problem.
With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die. </div></div>

If you use the same bushing in a neck or FL die it grips the neck the same, no way aroud it. Or running the same size expander ball through the neck is giong to pull the same the die doesn't matter. If you want to partial size the neck go for it but I'll pass on that, just another variable unless your going to trim to length every time.

"With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die."

If you cant maintain headspace with a fl die your giong to have problems with a body die also, they size the same way minus sizing the neck. </div></div>
I was not talking about a bushing type die.
There is no way that you can bump the shoulder with A STANDARD FULL LENGTH SIZING DIE as accurately as you can with a BODY DIE.
</div></div>
I know you not talking about bushing dies, you said a neck die grabs the less than a full length die does which it doesn't.

The body die and full lengeth die are cut with the same reamer. Unless you order and have them make you a custom die.
 
Re: to full length re size or not?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C.K</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: C.K</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Country</div><div class="ubbcode-body">First off a FL die ( standard Full length die) is not the same style of die compared toa neck size only.
When you size in a standard FL die as you extract the case the die holds onto the necck with greater grip than a neck size only die generaly speaking. Some standard neck dies with expander balls will also stretch the neck and shoulder if the brass is thick or the die extra tight. However at least with the neck size only die you can reduce the length of the neck that is sized , reducing the potential problem.
With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die. </div></div>

If you use the same bushing in a neck or FL die it grips the neck the same, no way aroud it. Or running the same size expander ball through the neck is giong to pull the same the die doesn't matter. If you want to partial size the neck go for it but I'll pass on that, just another variable unless your going to trim to length every time.

"With the standard FL die you can't partial size very well and maintain good headspace control like you can with a Body die."

If you cant maintain headspace with a fl die your giong to have problems with a body die also, they size the same way minus sizing the neck. </div></div>
I was not talking about a bushing type die.
There is no way that you can bump the shoulder with A STANDARD FULL LENGTH SIZING DIE as accurately as you can with a BODY DIE.
</div></div>
I know you not talking about bushing dies, you said a neck die grabs the less than a full length die does which it doesn't.

The body die and full lengeth die are cut with the same reamer. Unless you order and have them make you a custom die. </div></div>
The full length die does grab a bit more because there is more sizing going on. More extrusion and lengthening of the case . This will cause a heavier extraction force to get it out of the die and as a result more stretching at the shoulder happens than compared to a neck size only.
That is why you have to push the case further in than you really require to get it resized however most loaders don't realise this is going on. Untill you start to try and partial size with a standard full length die .
You can believe what ever you want but thats been a know drawback of standard old fashioned full length dies for many years.