Seems like I read somewhere that i could neck size with my full length die. Can anybody tell me how to set up the die? RCBS full lenght die is what I have. Thanks.

Well, I don't think that is a best practice.

Neck sizing dies have a purpose by design, and though you might get a partial sizing of the neck, even remove the primer, it wouldn't be a true neck die equivalent.

As inexpensive as the Lee Collet neck sizing dies are just get one for your caliber if available. Midway has excellent prices and you don't have to lube the cases in Lee's collet die. I've been using these dies for years now and they increase case life by 10 times at least. Some of my 243 cases have over 20 firings on them.

Using a FL sizer die to neck size is easy, although you will size the body of the cartridge a little too. The best part is, you dont need to buy another die, you already own it! 1) Hold the neck/shoulder of the case to be sized, a couple inches above the flame of a candle, and let it get black with soot. 2) Put your sizing die in your press adjusted with the bottom of the die about 1/4" above the shellholder. 3) spray a little lube on/in the case neck as usual, and try sizing it. 4) Continue to size this case, and slowly adjust the die down between sizing, watching the amount of soot that is being worn off the neck (it will be obvious where the sizing starts/stops, as it will leave a clean spot where the sizing is taking place). 5) Stop moving the die down and tighten down the lock ring right before the clean line on the neck reaches the joint where the neck meets the shoulder. You will probably need to set your capper/expander lower in order to punch out the old primers. This setting on the sizer won't bump the shoulder back, will resize the neck, and will also size the body down a little also, depending on the particular cartridges designed taper. Try it, it may work very well for you in a rifle that doesnt need to be FL sized.

I had read about that procedure but wasnt sure if thats what I needed to do. It wasnt actually called neck sizing. Thanks

Thats actually called partial resizing, a real neck sizer works the brass less. The Lee dies are very good and very inexpensive.

I made an interesting discovery lately that may apply here. Watch out for this as it may cause you to deform the webbing of the case.

I found that I had limited my sizing with the expander being too low and actually contacting the webbing (bottom) of the case. I thought I had the die against the case holder but when I moved the expander and decapper up out of the way it was obvious what was going on. I would never have thought it. Dugh!

Partial sizing as described by Fatelvis works pretty well. I found that I needed to lube the entire case body for my .257 Roberts to work smoothly through the partial sizing procedure because the body was being sized somewhat even when the soot was only removed from the neck.

I used an old automotive feeler guage to measure the distance between the shell holder and the base of the die once it was set correctly. That will allow me to get the die set right even if the locking collar somehow gets moved.

I have found that I can size about .25" of a 22 hornet neck in a full lenght die without hitting to body of the case. The 30-06 started sizing the body at about the same time as the neck. So I guess it depends on the taper of the cartrage as to weather you will hit the body if trying to necksize only with a full lengh die.