Have had some problems with runout when using Redding dies to full length size brass for my 280AI. This is Norma brass that has been fired 3 times and just neck sized in the past with Wilson bushing dies.
I suspect the runout, approx .005 and sometimes more, is caused by the sizing button. I have tried a loose decapping stem in the die, a rubber o-ring washer under the locking nut on the stem, Imperial sizing wax and other lubes in the case necks and nothing seems to correct the runout.
I removed the complete decapping stem assembly from the die and resized the brass and found runout reduced to .001-.002. Next step is to try a floating carbide sizing kit from Sinclairs and see what happens. These buttons eliminate the need to lube the case necks but they are expensive at $18.50 for each caliber.
First off will they help solve the runout problem and are they worth the cost?
Comments please.
Thanks. Chief

quote:

are they worth the cost?

IMO.....NO.

Chief

My first reaction would be to simply let the bushing float in the die body. Second would be to call the maker and explain the problem to them. You may have a bad bushing. I'm sure they would be willing to work with you on a replacement.

Ray

I.M.O. yes

quote:

Originally posted by cropduster:
I.M.O. yes

For the cartridges that I am concerned with run out on, I decap with a universal decapping die and size with the Redding S type bushing die without the sizing bushing installed.

Like Fjold, I also decap using a Universal decapping ide - mine's a $7 Lee. Doing it that way, there's no reason to have the expander button pulling up and dragging the shoulder out of shape, and I can then resize without the decapper.

You said you tried a loose stem, but presumeably it was loose for the "pull" (out) stroke. You might want to try a loose stem on a "push" in stroke on the already-decapped case. You can't do it with all sizing dies (such as Lee or Forster), but for those (such as RCBS) it works fine and seems to disturb the neck much less.

Jaywalker

Redding type S full length sizing bushing dies come with a decapper that can be used with or without an expander button. Great for problems like yours. But since you have wilson bushing dies already, you dont want to invest in more dies. Your Redding fl die can be converted to a busing die, they can be found at benchrest central. Or you could maybe get a body die from Redding ($33), this is a full lenght sizing die that does not touch the neck area. I dont think a floating/carbide expander button will fix your problem.

Guys

This is all getting very confusing for this ignorant Illinois farm boy. Maybe one of you can help me out here?

It sounds to me like one or more of you are using an expander ball with a bushing sizing die. The two do not go together. The only reason to use an expander ball is if your case necks are uneven or of varying dimensions. The ball will expand the inside of the neck to help in uniform neck tension. If that is the situation, then a few thou of case neck runout is NOT your biggest problem.

If your necks are uniform in thickness then you use a bushing to size the outside of the case. Don't touch the inside. A properly sized bushing in a quality die should result in concentricity every time. If it doesn't then there is something wrong in your setup, the bushing, or the die. Or all three.

Where have I gone astray??

Ray

Gentlemen,many thanks for the replies. I'll now try to clear up some confusion about my orginal post.
I wanted to full length size some brass and test it against some neck sized brass from the same lot. All this brass had only been neck sized previously and I was curious if full length sizing would make any difference in group size. A Wilson neck bushing die was used for the neck sizing and a standard Redding die, not a S type or bushing type, was used for the full length sizing.
I had decapped all the brass using a punch and base prior to any sizing. On the first try of full length sizing I left the decapping assembly in the die even though it wasn't necessary. I then checked for runout and found what I think is excessive runout, .005 and sometimes more. This is when I resized again using the loose stem method (loose on push and pull strokes)with no improvement in runout. I resized again with a o-ring under the stem locknut in hopes this would reduce runout but there was no change. Finally I removed the entire stem assembly and resized once more and at last found almost no runout.
This is how I arrived at the conclusion that the expander ball or some part of the stem assembly, or my neck lubing, was causing my rouout problems and thought a floating carbide button would help. I do realize that this is a hunting gun and all this effort is not going to make it a benchrest gun but it is something I wanted to see for myself.
As side note I took the cases that were full length sized without using the stem in the die, expanded the neck with a mandrel enough to seat a bullet and loaded some rounds. Hopefully I'll get some time to shoot these soon and see what happens.
Thanks again for the replies, Chief.

quote:

Originally posted by Cheechako:
Guys

This is all getting very confusing for this ignorant Illinois farm boy. Maybe one of you can help me out here?

It sounds to me like one or more of you are using an expander ball with a bushing sizing die. The two do not go together. The only reason to use an expander ball is if your case necks are uneven or of varying dimensions. The ball will expand the inside of the neck to help in uniform neck tension. If that is the situation, then a few thou of case neck runout is NOT your biggest problem.

If your necks are uniform in thickness then you use a bushing to size the outside of the case. Don't touch the inside. A properly sized bushing in a quality die should result in concentricity every time. If it doesn't then there is something wrong in your setup, the bushing, or the die. Or all three.

Where have I gone astray??

Ray

Standard FL sizing dies have always sized the neck way smaller then needed to makeup for the difference of wall thickness in the brass necks of different manufactures. The expander then opens the neck back up to a useable diameter. A bushing die and expander can be used at the same time for necks that have not been turned. This is a good way to not over work your brass and keep runout to a minimum. Bushing dies on the other hand can still cause runout if you size the neck down more then .010"(see Redding website). All this is mostly a waste of time in a hunting rifle. Standard die sets will do in most all reloading operations if used correctly. Also, bushing dies(my 243win redding) do not size the neck all the way to the shoulder. If your going to neck turn, make sure you FL resize in a standard die first if using a Lyman type neck turner.You need to make a cut to the shoulder when neck turning.

Check your shell holder. It might not be square.