I am working up loads that will be used for hunting and have been told to stay away from neck sizing dies. What are the advantages and disadvantages of partial resizing over full-length resizing? Any info would be appreciated.

If you're loading for a pump, semi-auto or lever action, don't neck size. Cartridges for these weapons should be full length sized to feed consistently.

If you're reloading for a bolt action or single shot weapon, neck sizing is the way to go since the cartrige has essential been sized to fit the chamber of your gun and there will be less expansion when you shoot it and thus less case stretching and fatigue. There is no disadvantage in using neck sized cartriges for hunting.

Here we go for the vast majority of Die Sets. This does not include the Lee Swaging/Crimping Die Sets which are unique unto themselves:

Full Length Resizing (FLR)
1.Reforms a Case to fit within any Chamber that meets SAAMI Specifications.
2.It has some unknown amount of Headspace.
3.The CenterLine of the Case and the CenterLine of the chamber are not in alignment. On Fixed Ejector rifles, the Case lays on the bottom of the Chamber. On Spring Ejector rifles, the Case is skewed to the opposite side of the Chamber from where the Ejector is pushing against the Case Head.
4.You set the FL Die by screwing it in until it touches the Shell Holder on a raised Ram, lower the Ram, screw the FL Die in an additional 1/4 turn and set the FL Die Lock Ring.
5.You have short Case Life due to Incipient Case Head Separations.
6.Accuracy is generally acceptable to fine.
7.You only need a Full Length Resizing Die Set.
8.Intended for use in Dangerous Game Rifles, semi-autos, pumps and most single shots.
9.You must Lube the cases and then remove it.
10.No need to ever Re-adjust the Fl Die Setting for use in any rifle of the same caliber.

Partial-Full Length Resizing (P-FLR)
1.Custom fits a Case to a specific Chamber.
2.It has a slight "crush fit" to eliminate all Headspace.
3.The CenterLine of the Case and the CenterLine of the Chamber are forced to be in perfect alignment. The Case is held in Tension between the Bolt Face and Chamber Shoulder, regardless of the Ejector type.
4.You set the FL Die by screwing it in until it is about the thickness of a Nickel above the Shell Holder on a raised Ram. You Lube and Resize a Case, remove the Lube and try it in the Chamber. Lower the FL Die 1/8th turn or so and repeat the process. You might reach a point where you CAN NOT close the Bolt or where it is very difficult to close. Screw the FL Die in 1/16th turn and repeat until the Bolt closes with "snug" resistance. If you go too far, back the FL Die up 1/8th turn and try again on a different Case.
5.You have the longest possible Case Life due to Zero Headspace.
6.Accuracy is generally fine to excellent.
7.You only need a Full Length Resizing Die Set.
8.Intended for use in Bolt Action Rifles and some single shots.
9.You must Lube the cases and then remove it.
10.You may need to Fine Tune the FL Die adjustment the first couple of Reloads.

Partial-Neck Sizing (with a FL Die) (P-NS w/FL)
1.May or may not reform part of the Case Body depending on how closely the FL Die dimensions match-up with the Chamber dimensions and is best used in one specific Chamber.
2.It has some unknown amount of Headspace which varies with each shot until the Bolt will no longer close and then the Shoulder must be “Bumped Backâ€.
3.The CenterLine of the Case and the CenterLine of the chamber are not in alignment, but become closer with each shot until the Bolt will no longer close. On Fixed Ejector rifles, the Case lays on the bottom of the Chamber. On Spring Ejector rifles, the Case is skewed to the opposite side of the Chamber from where the Ejector is pushing against the Case Head.
4.You set the FL Die by screwing it in until it Resizes approximately 1/2 of the Case Neck or less.
5.You have shorter Case Life than P-FLR, but longer than FLR.
6.Accuracy is generally fine to very good.
7.You only need a Full Length Resizing Die Set.
8.Intended for use in Bolt Action Rifles.
9.You may or may not need to Lube the cases and then remove it.
10.You may need to Fine Tune the FL Die adjustment the first couple of Reloads.

Neck Sizing (NS)
1.Only reforms the Case Neck and is best used in one specific Chamber.
2.It has some unknown amount of Headspace which varies with each shot until the Bolt will no longer close and then the Shoulder must be “Bumped Backâ€.
3.The CenterLine of the Case and the CenterLine of the chamber are not in alignment, but become closer with each shot until the Bolt will no longer close. On Fixed Ejector rifles, the Case lays on the bottom of the Chamber. On Spring Ejector rifles, the Case is skewed to the opposite side of the Chamber from where the Ejector is pushing against the Case Head.
4.You set the Neck Sizing Die by screwing it in until it Resizes any amount of the Case Neck you desire.
5.You have shorter Case Life than P-FLR, but longer than FLR.
6.Accuracy is generally fine and gets better with each shot "until" the Case Shoulder needs to be "Bumped Back" slightly.
7.You need a Neck Sizing Die and will eventually need a Full Length Resizing Die unless you trash the Cases once they need the Case Shoulder moved back.
8.Intended for use in Bolt Action Rifles.
9.No need to Lube the cases.
10.No need to ever Re-adjust the NS Die Setting.

HC is mostly right

He has failed to factor in the stages a case goes through from new to well used.

With new cases you have no choice, the headspace and sizing has been done for you at the factory. Most of the time the headspace is significant. New cases can have as much as .015" headspace. I've measure it many times.

After firing the first load the case expands to where it is almost chamber size. There is no crush fit and it has the same dimensions as a PFLR'ed case, i.e. headspace between .0015" and .0005". On each subsequent firing it approaches a crush fit and zero headspace a little at a time. On the 3rd or 4th firing it develops a crush fit and zero headspace.

Now at this point, you really don't have a choice of neck sizing further unless you like grinding the loaded case into the chamber. You need to push the shoulder back. You can push the shoulder back with either a FL die or a Body Die. I prefer to use a neck sizing die until the shoulder needs to be pushed back and then use both the neck sizer to size the neck and the body die to push the shoulder back on later loadings. Gives me more control.

Using the Stoney Point Head and Shoulders Gauge you can keep track of all this and set the Body Die so that the case shoulder is pushed back exactly .0015" where I get a very very slight crush fit. That way I know that I am working my brass the least amount possible and the case conforms to the chamber the most possible.

Where HC and I disagree (he's wrong of course ) is that when you neck size only and do not have a crush fit you have the same end dimensions as PFLR, that is the headspace is less than .0015". It is not necessary to push the shoulder back if you are already within those limits.

Where we agree (he's right on this one ) is that after the crush fit develops it's PFLR on all subsequent loadings.

I just need to talk him into getting a Stoney Point Head and Shoulders Gauge and he would see what I mean.

quote:

Originally posted by woods:
HC is mostly right ...

Hey Woods, Now if you had only said, "HC is right - as usual!", then you would have had a much better start.
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I think of the Stoney Point thingys kind of like the old Boone's Farm Wines and any Wine Coolers - the farther I stay away from them, the fewer headaches I have.

quote:

I think of the Stoney Point thingys kind of like the old Boone's Farm Wines and any Wine Coolers - the farther I stay away from them, the fewer headaches I have

Eh Hot core I like that simply because it is the truth.

Thanks Fred. The truth is tough on some "thingys".

quote:

Originally posted by molar1:
I am working up loads that will be used for hunting and have been told to stay away from neck sizing dies. What are the advantages and disadvantages of partial resizing over full-length resizing? Any info would be appreciated.

You want to full-length size all hunting loads as insurance against mis-feeds, ie, assuring ease of chambering.

There is no disadvantage to partial re-sizing other than the finished rounds will be suitable only for the one rifle. The advantages are extended case life and a custom-fitted case for the chamber.

Partial full-length sizing with a bushing die will give further case life extension and straighter necks.