How do Wilson dies expand neck?

[willyCJ]

I just ordered a 30BR and I'm planning on spending quite a bit of this winter improving my reloading knowledge.

At this point, Wilson dies have crossed my reading list, but I'm a bit confused.

I've used RCBS and Redding dies. In my experience, as you size a piece of brass, you first size the outside of the brass,either neck or full length). As the brass is removed from the die, the expander mandrel sizes the inside of the neck.

On a Wilson die, only the outside of the neck is sized, correct?

So my real question is why does a Wilson die not require the inside of the neck to be expanded? Or is this part of the ability to get neck tension in a piece of brass?

 

[Preacher]

The Wilson dies are neck dies with bushings, and if you use different bushings you would also need a new expander each time you changed neck bushings.......
Sooner or later you will need a full length die unless your running kinda slow
velocity wise. Even your FL bushing dies don't have a expander in them.....

 

[JHardy]

The expanding ball,unmodified) on size dies is usually a detriment to competition accuracy in most instances as the ball being pulled back through the case usually induces runout.

Some dies have the ball located nearer the top of the die and some further down the body. Some expander "balls" are not balls but smooth elongated expanders. Some function well and some are horrible.

If you use the Wilson dies,great), remember that they only size the neck. If you need to FL size your brass so that it chambers well all the time -- and if you are looking for the best accuracy at long range -- remove the size ball entirely from your FL die. Run your cases through the FL die with or without a neck bushing,get a bushing FL die and not just an off the shelf FL die). If no neck bushing is used, then run them through the Wilson neck die.

You can purchase an expander die and expander mandrel combo,inexpensive) as this does a better job of "expanding" without causing problems.

There are some advanced techniques where an expander is used in combo with neck bushings and specially turned necks to get a very exact bullet pull,neck tension). However, except when the brass is new and unfired -- and if the neck gets a ding -- you seldom have to use an expander.

I hope this helps,
Jim Hardy

 

[Cheechako]

willy

If you are using neck-turned cases or high quality brass such as LAPUA you can simply measure the diameter of a loaded round and deduct the amount of tension that you want. For example, if your loaded round measures .2700 and you want .003 neck tension, you use a bushing size .267. No mandrel or expander is needed.

That's the way most competition shooters do it.

Ray

 

[mikecr]

Ray nailed it.
And there is no 'expander' at all in a Wilson. It's just a decapper/case ejector rod.

As mentioned earlier, if for some reason you need expansion,new brass, or necking up a wildcat), Sinclair offers a very good expander system.
I use this just prior to seating each bullet, to drive outward any thickness variance and get a measure of tension on each case. This works well as the Sinclair mandrels are just the right size to give me straighter seating without changing the tension I set through neck sizing.

 

[willyCJ]

That makes really good sense. I may pull my expanders out of my other calibers and see where they resize the brass to. If I can get away with not expanding, I would be happy.

So here is my 2nd question. A wilson seating die doesn't touch the neck when seating a bullet. Thus, they don't offer different dies for different neck turning setups. All of the tension is put in place by the bullet expanding the neck by 0.002,or whatever the tension is set to).

I was looking at the picture on the last page of: http://www.lewilson.com/images/2008_LE_Wilson_PBookFinal_Large.pdf and was surprised that the die wasn't tight around the neck, and then I thought about it some more.

Thanks again guys.