When to neck size?

Reece123

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I know you can only neck size if you're using the same chamber, but im more questioning when is it worth it to only neck size?
For example, Im loading up some 243, 6.5 Creed and 6.5 PRC that will probably only ever be used in their respective rifle. All of these are using Hornady brass and are for hunting/hobby target shooting, no competitions etc. Is it worth it to spend another $50 per die for an RCBS Neck sizer for each one or does that not come into play until you're shooting competitions, using expensive brass, etc etc?
 
For any of my more precision rigs, I only neck size with a Lee Collet Die until I get positive heaspace. Usually 1-3 firings. Then I bump the shoulder back .02. Saves a lot of brass working on the case, especially with belted magnums.

To be honest, I don't even measure. I run Redding competition shell holders, and when I can feel positive headspace, I start with the thickest deck shell holder and just drop down sequentially till feeding is smooth. This way I get full engagenment with the shell holder to the die bottom, which decreases variences due to any play in the press.
 
I neck size only till after the 3rd firing in my stw (belted case .020" growth). On this 7PRC I need to fl size after the 1st firing because there is only a .003" shoulder difference between new brass and fully formed.
 
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I neck size only till after the 3rd firing in my stw (belted case .020" growth). On this 7PRC I need to fl size after the 1st firing because there is only a .003" shoulder difference between new brass and fully formed.
I recently picked up a 6.5 CM Christensen Arms that is exactly like ypur PRC - .02 back to starting after each firing is perfect. Brass lasts a long time.

A lot of belted mags take a few firings to reach full length. Once full chamber length, I headspace off the shoulder like nonbelted cases.

I have a 6.5 PRC Tikka that I've fired some brass in 4-5 times and not touched the shoulders. And its a tackdriver.
 
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With my .338 I neck size the first few times till the brass gets snug in the chamber, then bump the shoulder after that.
 
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I only full length size. My reloads shoot fine and according to @Formidilosus full length sizing results in more reliable rifle function.

The real question to me is why do something other than FL sizing? What are the benefits and have they been measured properly?
 
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full length sizing results in more reliable rifle function.

The more slack there is between the chamber and the case, the less likely it is to have a problem. Throw in some environmentals like dirt, water, snow etc and it gets worse. Ammo I bring hunting is always FL sized and target ammo gets bumped back just enough to fit, for the sake of brass life. Im a cheap ass bastard and getting one extra firing out of a $2.50 case makes me happy.


The real question to me is why do something other than FL sizing? What are the benefits and have they been measured properly?

Brass life with belted mags is my reason. The delta between a FL sized case and the chamber are what would determine the value in it. With some rifles im sure full length sizing still gives a tight fit and minimal case stretch. With my .338 it takes 3 or 4 firings before the cases even need sizing. Its a grower.
 
IMO it's never worth it.

What are you trying to gain?
What is your experience with neck sizing?
I never do. Im in the camp of always full length size everytime
As above
I only full length size. My reloads shoot fine and according to @Formidilosus full length sizing results in more reliable rifle function.

The real question to me is why do something other than FL sizing? What are the benefits and have they been measured properly?
As above, or are you just repeating what you have heard?
 
I know you can only neck size if you're using the same chamber, but im more questioning when is it worth it to only neck size?
That’s not necessarily true, modern well built rifles such as Tikkas, Sakos etc keep dimensions to much closer tolerances and neck sized ammo will interchange until cases stretch , then they will need body sizing for all.

I wouldn’t bother neck sizing junk brass like Hornady , but when you are using quality brass like lapua case life is crazy long, I am loading 223 cases with well over 30 loadings on them and 243s into the 20s.
The brass work hardens in the head and doesn’t change dimensionally after a while.
I will add to this tomorrow.
 
As above, or are you just repeating what you have heard?
As above what? If you are referring to the excellent explanation given to me by @Choupique that was in answer to my question you quoted.

There was no valid reason given prior to my question. I made no argument with the idea of trading reliability for brass life.

As for me just repeating what I have heard, are you arguing that only neck sizing or shoulder bumping does not effect reliability? Or, did you just have a compelling need to pretend to have an answer while not adding anything of value?
 
As above what? If you are referring to the excellent explanation given to me by @Choupique that was in answer to my question you quoted.

There was no valid reason given prior to my question. I made no argument with the idea of trading reliability for brass life.

As for me just repeating what I have heard, are you arguing that only neck sizing or shoulder bumping does not effect reliability? Or, did you just have a compelling need to pretend to have an answer while not adding anything of value?
Nice aggressive comeback, I asked you a simple question.
 
If you have to pull bullets, it's a good idea to neck size before installing a new bullet.

If you're doing load development and you got 10 cases you want to reload real quick, you can neck size those also. It saves you the time of annealing, setting up the full length die, and bumping shoulders which usually takes me a few minutes.

YOU DO NOT NEED and neck sizing die. Just adjust your dye so that you have a small visible Gap about 0.020 between the die and the shell holder, with the ram fully up so to speak. It'll size your neck but not the rest of the case. For years, I used a dime.

If you neck size more than once, the cartridge will grow and eventually you'll have had space problems real quick. Even with the same rifle. And if you change rifles, you're through stopped right on the spot..
 
As above what? If you are referring to the excellent explanation given to me by @Choupique that was in answer to my question you quoted.

There was no valid reason given prior to my question. I made no argument with the idea of trading reliability for brass life.

As for me just repeating what I have heard, are you arguing that only neck sizing or shoulder bumping does not effect reliability? Or, did you just have a compelling need to pretend to have an answer while not adding anything of value?
My initail post covered the main reasons for neck only sizing at times in the overall process: potential for a little more precision, longer case life. For belted magnums, because they head space off the rim instead of the shoulder and, by extension, often initially have excessive head space from the shoulder, case life with careful neck sizing until brass is closer to chamber size can be significantly longer.

If you carefully control headspace and continuously function test fired brass, you likely won't encounter functionality issues.I shoot quite a bit in temps ranging from 90 to below zero, always feed from the magazines when shooting my hunting rifles, and the only times I've had issues with function are with equipment failures such as broken extractors, ejectors, etc, which have been exceedingly rare and are just part of the game.

IME, there's a lot of folks who couldn't tell you much about how much headspace they are dealing with. Likewise, there seems to be some general confusion between full length sizing and shoulder bumping to a certain length with a FL die. Accordingly, as general reloading advice for assembling hunting ammo, to completely FL size each loading isn't really off the mark.
 
What is your experience with neck sizing?

Off and on with different calibers from .223 to .300wby over the course of 30 years. Never once did it produce better accuracy. It did make for plenty of tight chambering. I almost cost my dad a deer that way but he managed to figure it out on the fly.

Why do you ask? Did you actually want to know or is this another case of an internet solipsism thinking he’s the only one who’s ever done anything?
 
That’s not necessarily true, modern well built rifles such as Tikkas, Sakos etc keep dimensions to much closer tolerances and neck sized ammo will interchange until cases stretch , then they will need body sizing for all.

I wouldn’t bother neck sizing junk brass like Hornady , but when you are using quality brass like lapua case life is crazy long, I am loading 223 cases with well over 30 loadings on them and 243s into the 20s.
The brass work hardens in the head and doesn’t change dimensionally after a while.
I will add to this tomorrow.

I’ve hunted with brass that was north of 10 firings. As long as primer pockets are tight I’ll keep using it until it needs trimming or obviously needs annealing due to difficult seating pressure. I try to shoot 5x then anneal and trim in batches as needed but in reality I trim as a dead of winter activity and I have a nice backlog of brass that needs trimming but won’t likely get done until it absolutely has to.

If a brass case cost one dollar per case, that averages out to a dime per shot for a 10 round case life, and a nickel per shot for a 20 round case life. So once I get over about 10 firings, the marginal value of stretching that, really isn’t worth it to me. I don’t shoot my bigger calibers in really high volume, and for my 223 loads, I have literally buckets of brass that I have never even been back through and processed the first time, for my hunting ammo, I almost always set aside a few handfuls of AAC once fired brass, and often as not, after it’s reloaded that first time, I don’t even pick it up again.

Years ago when I used to shoot handguns a lot, I had a whole lot of both 45 colt and 45 ACP cases that had been loaded north of 20 times each, every time one of the 45 colt mouths would crack, I would anneal the rest of the batch, And eventually, I got tired of the project and just threw the whole lot away, because I have more brand new 45 colt brass than I will ever go through in my life, at the current rate. M point being, past some point, brass life just doesn’t matter that much. Diminishing returns.
 
If you are going to get one get the lee collet as it's cheap and you probably won't use it much. You can probably get away with only neck sizing every other brass cycle and it certainly saves time on lubing/cleaning. For your actual hunting ammo you should definitely shoulder bump .02-.03 for maximum reliability. Reloading is a journey and you'll have to figure out what is best for you over the long run
 
What is your experience with neck sizing?

As above

As above, or are you just repeating what you have heard?
I saw no accuracy gain the few times I have done it. Plus I hunt with a buddy who shoots the same caliber and load as I do, but a different manufacturer. FL sizing let's us share ammo if needed
 
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