Neck tension, the simple way...

[tek4260]

Simply turn down your expander until it freely slides into your sized case. Leave the radius at the top so it will still bell the brass to start the boolit. Now you have maximum tension, and the crimp is used to simply do away with the bell in the brass(since it really only prevents set back in autoloaders).

Lee
http://i292.photobucket.com/albums/mm35/tk3945/1357792541.jpg

RCBS
http://i292.photobucket.com/albums/mm35/tk3945/1357792537.jpg

The only thing needed is a drill press that is large enough to chuck up the expander, a file and sandpaper.

Almost too simple :)

Here are the effects.

Before,

http://i292.photobucket.com/albums/mm35/tk3945/Untitled-5-1.jpg

Notice the lack of neck tension and pull. This is with some old reloads using the same dies before I modified them. The load was 240gr LSWC over 22gr of 4227 shot in a 329PD.

This is what they look like now. Its not a good picture, but you can see the grease grooves in the boolit through the brass

http://i292.photobucket.com/albums/mm35/tk3945/DSCN1122.jpg


I realize this is contrary to what many think, but my revolvers seem to like it. My groups have shrank and vertical stringing is gone.

[GBertolet]

The down side of doing this, is you may inadverntantly size down you cast bullets when seating in the case. The factory expander ball size is almost always designed for jacketed bullets. And you are reducing it more yet. Your bullets may be very hard, and you can get away with this, but common wisdom dictates that this is not normally a good idea. Irregardless, I am glad it worked out for you.

[cbrick]

I've modified my expander much the same way but you do need to take care that you don't go too far. The result would be brass so tight that the boolit is sized down when seating.

Rick

[tek4260]

If it is soft enough to be sized down by the brass, it is soft enough to bump up to throat diameter when you fire it, which would negate any sizing by the brass.

[cbrick]

If it is soft enough to be sized down by the brass, it is soft enough to bump up to throat diameter when you fire it, which would negate any sizing by the brass.

Not always.

Rick

[44man]

If it is soft enough to be sized down by the brass, it is soft enough to bump up to throat diameter when you fire it, which would negate any sizing by the brass.
Not from me either.

[subsonic]

If it's soft enough to be sized by the brass, you will also not have much neck tension by default.

[MT Chambers]

Doing this leaves you no leeway in case you get thicker/thinner brass or a different make.

[leftiye]

Slug the bore. Make throats .001" bigger. Size boolits that same size. Make expander ball .002" smaller. Open up sizer die to size for minimal expansion (say .003 smaller than boolit at the. Brass doesn't spring back measurably, make die and expander ball the size you want to happen.

[44man]

Doing this leaves you no leeway in case you get thicker/thinner brass or a different make.
Doesn't matter if the boolit is tough. I use only water dropped WW boolits for my revolvers as none needs expansion on deer.
All of my brass shows the boolit base and GG ripples.
Shooting soft lead creates a million problems I just gave up on.
In the .44 I have loaded from .430" to .434" boolits with the Hornady expander without sizing a boolt.
I have said many times the amount of tension doesn't matter a lot as long as each boolit is held with the exact same tension but just making the boolit tougher and making them fit tighter and letting the boolit expand the brass will even things out better.
The Hornady expander is short and only enters brass 3/8" leaving the boolit base to go into brass that has not been expanded. Soft lead does not apply and I have no problems with PB boolits.
Leftiye says it good but I have never measured a thing. I will not open a size die and I have seen no difference between neck sizing or FL either. I just FL because after so many shots, brass will not chamber so it needs FL sized anyway.
Now I DO open rifle neck size dies to let the expander come through easier without bending the shoulders. Most rifle dies size the neck too much.