Neck Sizing

[majohnson2]

Using a 3 piece set of Redding dies I notice when I neck size fired cases, the entire neck of the case isn't completely sized. Roughly .0626 to .0925 of the cases neck remains untouch. In the neck sizing die I use a TiN coated bushing. As the instruction indicate the neck bushing is installed with the writing facing up. I also removed the inside ball from the neck sizing die after reading about how with the ball installed it has a tendency of twisting the cases neck.

Reading information on neck sizing on the Forester website, they indicate that partial neck sizing aids in better case alignment. Are you better off not completely resizing neck? My neck sizing is screwed down as far as possible and the decapping assembly is set to allow only a slight movement of the neck sizing die as indicated in the instruction sheet provided by Redding. I've read about custom shell holders ground to allow the case to extend further into the die.

Full length sizing does size the entire neck. And adjusting FL or the Neck sizing die gives me correct case neck and chamber set back. So there are no troubles in that process. I just not quite sure on which way to go with my reloading.

 

[ksthomas]

Re: Neck Sizing

majohnson,

You've answered your own question here; problems or concerns when N/S only, and yet everything is fine when F/S is done. Go to the F/L sizing each and every time, and discard the N/S process entirely. It's a sure way to incorporate problems that you'll never have to deal with if you stick to F/L sizing, and so long as your dies are adjusted properly (i.e., use a gage such as the RCBS Precision Mic to set headspace), it's no harder on the brass than Neck Sizing alone.

 

[rg1911]

Re: Neck Sizing

In the "For What It's Worth" column, I only neck size my bolt action brass and have never experienced any problems. I can live with 1/3-moa at 400 yards.

Now, after a certain number of reloads, the cases do stretch and I have to run them into a body die to set the shoulder back a hair so they chamber easily again.

My rationale is that the less I work the brass, the happier it will be. Especially considering the cost of Lapua brass.

Concerning partial sizing aiding alignment, it does make sense that the unsized area of the neck will conform more completely to the actual chamber neck dimension. This should have the effect of centering the neck more accurately.

As always, each barrel is different and YMMV.

Cheers,
Richard

 

[RTH1800]

Re: Neck Sizing

Kevin is abslouely correct of course. A .001 shoulder bump with F/L body sizing is not hard on brass. I have loaded some Lapua .308 Win brass 45 times then disgarded but it was not bad yet that I could tell. Fired in one rifle. Tight chamber on really little or no working of it. That with a stiff load of IMR 4064 and 168 grain SMK's.

 

[majohnson2]

Re: Neck Sizing

Kevin, I don't FL resize everytime given that it shortens brass life along with hurts accuracy.

There is so much info and so many contradictions. Then you get answers from people that don't know.

In neck sizing I had never come across anything about only sizing what is essentially half the length of the neck. I'm looking for more info about sizing, without find out the hard way.

rth1800 are you trimming your cases, 45 reloads thats amazing. The info I come across indicates .005 set back on the shoulders.

 

[ksthomas]

Re: Neck Sizing

majohnson,

there's two very common misconceptions that you've expressed here, and I'd like to address them both. One, that N/S extends the life of the brass. As I said, if done properly, F/L sizing gives you every bit as long of case life as N/S can, but without all the additional headaches that go hand in hand with neck sizing. You <span style="text-decoration: underline">will</span> have problems if you stick to neck sizing. It's not a question of "if" but only "when." I tend to believe in Murphy in these things, and he'll usually find you when you can least afford a visit from him. And Two, that Full Length sizing somehow produces less accurate ammo than Neck Sizing. It doesn't, and is generally the other way around. Virtually all accuracy labs that I'm aware of use nothing but full length sizing for all their testing, and accuracy is what most reloaders only dream of. I've fired literally hundreds of thousands of ten-shot groups, with well over 95% of them staying far below the 1/2 MOA mark. In fact, when a rifle wouldn't consistently hold 1/2 MOA or under, I scraped the barrel, as I could no longer use it for test purposes. All of that ammo was full length sized, NEVER neck sized, as it had to work in a variety of differnet guns. My predecessor at Sierra, Jim Hull, used to say that a loaded round should fit a chamber, "like a rat turd in a violin case." Jim had a way with words, and creating visual images. But the idea is that it should fit freely, without binding or jamming when chambered. Forget the nonsense about N/S ammo giving better accuracy, because it's exactly that; nonsense. A few isolated examples of individual guns or groups don't change that, and it's the long run averages that count.