Neck sizing: Noob question.

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longarm21

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Ok so everyone in the target shooting community seems to talk about neck sizing over, full length sizing. I am just getting into reloading, and I am at the "study" stage - have most of my equipment but need to build a bench, and acquire a few more things before I can start.

How does one "neck size". I have a full length die set. I have looked for neck sizing dies, am I barking up the wrong tree here?

I'll be reloading .308 WIN
 
Adjust the Full Length Sizing die by backing it off, run the case up into the die, turn the die down by hand until it touches the case and resistance is felt. Run the ram down, adjust die dow 1/2 turn, run the ram up,down inspect the case, What you are looking for is a little ridge on the neck where it is being squeezed back to size.
Keep following the; up, down, inspect, 1/2 turn process until you get the entire neck sized and then give it 1/2 turn more so that it just starts to adjust the shoulder.
Don't forget to measure your cases and loaded ammo to make sure they are still in spec. Also the cases and subsequent ammo now become gun specific, they are formed to ONE guns chamber, don't try loading them into another gun of the same cal. (It might be ok, but it might not!)
The idea is to let the body expand to the chamber of your gun thus eliminating any alignment errors associated with having a loose chamber and min spec ammo. Real pros go so far as to mark alignment(rotation) of their cases so that they always go into the gun EXACLY the same way.
 
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I don't personally, unless I experiance an issue with a case that necessitates a FL resize. If it gets sticky to load/extract,or dented on the body or shoulder than I annel, FL resise and re-fireform. (It gets difficult to FL resize after a few firings)
I allow my cases to expand to the chamber and then adjust the neck and just bump the shoulder. Every couple reloadings I annel the necks/shoulders with a propane torch and water.

I don't reload for 308win but do reload 6.5x55 wich is still a rimless bottleneck. I should also note that by neck sizing I experiance a longer case life and little to no case length changes.
 
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Get a Lee Collet neck sizing die and a standard full length resizing and try both for accuracy.

There are two schools of thought and they can depend if you have a standard factory rifle or a custom rifle with a custom barrel with a tighter chamber.

Some shooters think that neck sizing only produces the tightest groups because the cartridge case is a custom fit to your chamber.

Other shooters think that full length resizing with minimum shoulder bump produces the best accuracy because it gives the bullet a little wiggle room to be self aligning with the bore.

NOTE: With a standard full length or neck sizing die the expander button can pull the necks off center as the button passes through the neck if the decapping rod is not perfectly centered in the die thus creating excessive neck runout. The Lee Collet die compresses the neck around a mandrel with the shell holder pushing upward on the case instead of pulling downward over a resizing button. This reduces neck runout by eliminating expander button misalignment.

Many competitive shooters full length resize but seat their bullets long and jam the bullet into the rifling and thus center the bullet in the bore.

Below is what one of these top national shooters said about resizing cartridge cases that is funny and needs a little thought.

"I get my best accuracy when the cartridge case fits the chamber like a rat turd in a violin case".

All the resizing methods above deal with aligning the bullet with the bore before you pull the trigger and each will depend on you and your rifle.
 
+1. I never FL size unless I have feed issues. I usually have to toss brass for wear before I feel I need to FL size it.

What gun are you shooting .308 Win out of, OP? I reload for .308 my Norc M14 and I'm up near 7-8 reloads on some of my brass. The fairly violent extraction chews the hell out of the rim and that tends to doom the brass more than the case walls or necks wearing out.

ciphery said:
I don't personally, unless I experiance an issue with a case that necessitates a FL resize. If it gets sticky to load/extract,or dented on the body or shoulder than I annel, FL resise and re-fireform. (It gets difficult to FL resize after a few firings)
I allow my cases to expand to the chamber and then adjust the neck and just bump the shoulder. Every couple reloadings I annel the necks/shoulders with a propane torch and water.

I don't reload for 308win but do reload 6.5x55 wich is still a rimless bottleneck. I should also note that by neck sizing I experiance a longer case life and little to no case length changes.
Click to expand...
 
I have looked for neck sizing dies, am I barking up the wrong tree here?
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Neck sizing dies are available (Lyman, RCBS and others offer them) . . . they look/function like a normal full length sizing die but only size the neck portion of the case. Some companies (Redding for instance) offer neck sizing dies with interchangeable bushings. This quote from an older Redding catalogue explains the concept better than I could.

By selecting the correct bushing, you are now able to provide just the right amount of neck tension to properly hold the bullet without excessive resizing.

Just a few more alternatives to what has already been suggested.
 
ciphrey's instructions are NOT a process for neck sizing, it's called "partial full length sizing" it can aid in lengthening your brasses life span but it still resizes the body (atleast the portion that enters the die) all you are doing is NOT bumping the shoulder back, this is fine to do but I personally wouldn't bother, I have friends that swear by this process and you may like it too however.

i'm sorry but in order to properly neck size, you need a neck sizing die. (I use a lee collet, and have used RCBS neck sizing dies aswell)
I recommend the lee collet neck sizing die. I will only FL size again when the brass fails to chamber, I check the brass in the rifle everyonce and a while, snug is OK, there is a lot of power in a bolt actions locking system.... you'll get it in there.

good luck! and most of all have fun!

also if you're reloading for a semi auto, you want to FL size every time.
 
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Thoughts on Federal Brass? I have about 150 rounds worth of brass I've kept from my factory rounds. I also have about 150 Hornady match brass also factory. Going to be using 178 gr Sierra Match Kings most likely.
 
longarm21 said:
Thoughts on Federal Brass? I have about 150 rounds worth of brass I've kept from my factory rounds. I also have about 150 Hornady match brass also factory. Going to be using 178 gr Sierra Match Kings most likely.
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I have two AR15 rifles and a five gallon bucket of Federal .223/5.56 brass, I stopped prepping these cases because I was having a 50% failure rate on stretched primer pockets after the first firing. Some say the brass is too soft and other say the brass is too thin at the flash hole and this causes the problem. I have heard others say that Federal has fixed the problem but it doesn't help with the brass I have.

FCvsMilbrasssectioned_zpse9aa074d.jpg


I tumbled several hundred Federal cases, removed the primer crimp, uniformed the primer pockets only to find out over half the primer pockets were too loose. The photo above is from AR15.com and there is a sticky about the loose primer pocket problem in the reloading forum and how to check the cases before prepping them.
 
fire until primer is loose, then in the metal recycling can.
My mil brass is fine, winchester brass is getting loose pockets easy.
 
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