After firing a case in my chamber for the first time I will size only 1/2 the neck in an RCBS FL die. I coated a case with some white dry lube powder to see if there is any contact and there is non other than the desired section of the neck.

Is the only advantage to using a neck die that the expander does not pass throught the neck?
What is the undesirable affect of the expander ball passing through the neck if you intend only neck sizing?

The expander ball usually pulls the neck out of alignment with the case, since the case and neck are unsupported when the ball is raised up through the neck. The resulting case may have runout of .007" or more. It lengthens the case quite a bit, as well. The effect is probably not enough to bother hunting ammunition, if you find 1.5" groups at 100 yards satisfactory.

This effect can be minimized by experimenting with the expander ball position, rotating the expander ball stem and measuring runout until minimum runout is achieved with a particular setting of the stem.

Neck sizing is fine as long as the resulting round will chamber easily. Hot loads and/or numerous reloads will usually make the round difficult to chamber after a while.

If you prefer neck sizing, as I do, the Lee collet die does an excellent job, with runout usually .001" or so. It is the way to go for extreme accuracy on a budget. Loads less than maximum will give several loadings before the case needs to be squeezed back into shape with full length sizing.

Of course, neck sized cases will usually go back into only the chamber in which they were fired. You cannot use them in different rifles.

EXPRESS & KLN,

KLN, you're right about the expander ball distorting the alignment of the case neck. By adjusting the decapping stem, this is easy to correct. Before finally going to the Redding competition bushing die, which elimenates the problem completely I found a method to get around the problem. The only drawback to it is that it requires the use of a universal decapping die to remove primers. Which is ok since this offers a perfect time too clean primer pockets. Remove the decapping stem from the die and adjust the die as needed to get the resizing you want. Reinstall the decapping stem but do not lock the stem nut. Select a case that has the best case neck thickness uniformity.Run the case into the die and with it at the top of the stroke, screw the stem up until the expander ball is touching the inside of the case, then back it off about 2 revs. Lower the case until the case neck is still in the neck portion of the die and has started down over the expander. At this point everything is in alignment. Now lock down the stem lock nut. the cases will never be pulled out of alignment again, except to the extent the the neck itself is out of alignment due to variations in neck thickness. While it is not perfect, its the best I could come up with. I hope that this is of some help. Good luck.

[ 06-23-2003, 01:32: Message edited by: BigBob ]

OK, good answer KLN.

Now I wonder if I want to de-prime and only neck size with the FL die...I could substitute the expander plug and de-capping pin with a .224 caliber one?

OR universal de-cap, then set the expander ball to enter only as far as the neck is being re-sized?

Do I actually need to expand the neck to allow for bullet seating?

Bob, looks like you posted while I was writing mine...Took the thought right outa my mind.

Thanx guys.

I just bought a K&M expander iron, and it works like a charm.
I pulled the expander ball off my Forster BR neck die, and left the decapping pin in.
It requires a differant procedure for expanding the mouth, but it makes the bullet seating really smooth, and doesnt tear up the case mouth....sakofan...

Using standard full length resizing dies, you generally need the expander ball. The factories produce the dies to accommodate all possible neck thicknesses, which necessitates sizing the neck too small and bringing it back to correct inside dimension with the expander.

Again, the Lee collet die will do what you want with a lot less trouble and expense than other options.

KLN had some very good points about using an expander ball. For a while, I had a lot of runout (.006 to .009) using the standard expander ball with FL sizing dies. Switched to carbide ball (Dillion Precision) which is very smoothe. Installed the ball in my Redding FL die. Cut the runout down to about .003 max; sometimes as low as .001 on the bullet. Also, with the carbide ball, a little bit of lube (One Shot) angled into to the neck during application goes a long way.

Have also reduced runout by sizing the case, turn it 180 degrees and re-size again.

I like the concept of the Lee collet die if possible. But at some point you will have to FL size back to something that fits your chamber again.

I have found that each gun may give different results with different sizing techniques. Example: my 223 likes FL sizing with the die backed off the sizing ram about 50 thousands. This is because the chamber is so damn big. (Remington is replacing the barrel.

My .22-250 seems to work best with FL sizing with shoulder bump-back of about .001. It also did great with Lee collet die except that you have to FL size after 4 or 5 firings. So rather than having Lee-sized cases for 4 shots and a FL (.001 shoulder bump-back) for the next round, I chose the FL (.001 back) for consistency. My chamber is fairly snug so brass-working with the FL sizing is reduced. It seems to depend on the chamber size.
Ron

I finally gave up and started purchasing Wilson bushing neck dies. I don't even use a press
for it, just a little rawhide mallet. The case is fully supported, and I'm sizing about half the neck or less. If you want to use a press the Redding "S" bushing neck die is a good choice. You can also simply back off a full length sizing die a turn or two to neck size, but your case will not be fully supported so you'll still get some runout. Best wishes.

Cal - Montreal