Die Question

[Savage_Jake]

How do you set up a full length die to just neck size?
I have a batch of .308 that need to be reloaded and I wanted to leave the case body alone.
I know I should just get a neck sizer, but if I can use my FL set that would be great.

 

[Enios]

Re: Die Question

Get a neck sizer no way of just neck sizing with a full length die. That's why they sell different dies.

 

[bohem]

Re: Die Question

You can do it by running the die short and only sizing part of the neck.

Some rifles actually like this, one of mine does, most of them don't.

Leave about 25% of the neck unsized if you want to try it. It has a tendency to form donuts though, which will screw you good when they show up and you'll have to size/ream/trim the brass to get rid of them.

 

[former naval person]

Re: Die Question

Even running it short you will size some of the body...which has a tendency to lengthen the case...sometimes to the point where it is difficult to chamber the round. Get a Lee collet sizer if you want to keep it inexpensive. They work well. JMHO

 

[Enios]

Re: Die Question

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: former naval person</div><div class="ubbcode-body">Even running it short you will size some of the body...which has a tendency to lengthen the case...sometimes to the point where it is difficult to chamber the round. Get a Lee collet sizer if you want to keep it inexpensive. They work well. JMHO </div></div>

Thank you, I preach this all the time. There is no way to PARTIAL resize with a full length die. You are making the case longer anytime you put it in a full length die and it has to go in deep enough to knock the shoulder back. I've seen tight dies that will lengthen the case over .004 before it knocks the shoulder back any. Yes you may not get it in far enough to size the web but thats the only thing you are not changing and that's one of the reasons for the bulge in the case just above the web. If you want to neck size, get a neck sizer and save the life of your brass. I have some custom honed dies that only set the shoulders back .001 and in .001 and .002 at the web, but they even will cause the brass to grow .003 before the shoulder is set back so I only use them when some of the rounds start getting a little tight to bolt and then I do all in that box.

 

[Greg Langelius *]

Re: Die Question

All this is true, but...

Case wall length growth will result in headspace shrinking.

Until it reaches the point where chambering is affected, this is not an especially bad thing.

The issue becomes one of case wall thickness, and decreasing the number of F/L sizings may decrease the tendency of creating the dreaded internal ring-groove just above (roughly 1/4-1/2") the extraction groove and may decrease the tendency toward case head separation.

Once chambering becomes an issue, simply running the F/L die down and doing a complete F/L resizing will bump the shoulder back and restart the cycle. IMHO, anything which reduces the number of shoulder bumps is beneficial to brass life.

Another issue is that when the rearward portion of the neck remains blown out, it serves to provide a partial interference fit between the case neck and the corresponding neck portion of the chamber, which can serve to center the casing's forward portion more concentric relative to the rifling. I think this can also be beneficial to accuracy.

One of the issues of case concentricity involves how the cartidge lies in the chamber prior to ignition. All the concentricity in the world becomes academic if the case itself is lying loose in the bottom of the chamber, several thousandths below the chamber centerline.

Greg

 

[ltfirehunter]

Re: Die Question

Redding makes some excellent dies that addresses most of your questions.
At some point in time you will need to use a body sizing die to take the bulge from the bottom of the case around the webbing areawhich can sometimes make it sticky in the chamber.
The competition die set set will allow you to neck size only with a bushing to control the desired neck tension, and a body sizer die that will leave tour shoulder in place.
The seater is micro adjustable.
They are a little pricey but well worth the money.

 

[BLAWTON]

Re: Die Question

The more you just neck size the harder you make the brass everytime you fire it.

 

[Enios]

Re: Die Question

That's why I neck size only a portion of the neck and use a custom honed full length so it does no more than necessary when it's time to full length. I also anneal the brass when it gets time to FL. I use the Redding Micro neck sizer with the 308 but all my sizers but one is bushing and either Redding or Forster and only use the Forster Micro seaters. I use the body dies when I Full Length or the Full Length with the bushing out I like to do the necks in a separate step without the expander.