221 to 300 sizing, offcenter...?

[no7fish]

Guys, I'm getting into sizing some .221 Fireball brass using the Hornady .300 Whisper dies in a RCBS single stage press. For some reason the neck always comes out offcenter when i size it.

I have tried both #4 and #3 shellholders (niehter was supplied or indicated on the die case) and both produce the same results. I have also tried sizing first up to 6.5mm and then to .300 with only a very slight improvement.

Any suggestions??

[Alleycat]

Does it correct itself if you rotate the brass 180 degrees? Or do you have some bad brass that is thicker on one side?

[no7fish]

As best I can tell it appears to be determined by the position my shellholder is oriented, but the brass isn't loose in the holder...? Could it be the shellholders are suited properly to the ram in my press?

I suppose it's possible the brass is not uniform, but I wouldn't expect it to be so consistently non-uniform.

[amafrank]

Do you have the expander ball in place???? without it the case mouth could drift a little though the case walls should keep it centered unless your ram or shell holder are pushing it offcenter.....

Frank

[no7fish]

Well I tried it last night with the regular resizer die instead of the one specifically for sizing up the brass (assuming i'm understanding what each of them are... I have a three die set, one bullet seater, one decaper/resizer, and another that i assumed was the one for sizing up to .300).

Anyway, I tried it with the decapper and that seemed to work fine. I think brass or my press are not consistent enough to hold it in the center, but the resizing die holds the body of the case and sizes the outside of the neck too, keeping it center. It also seems to straighten some of the previously offcenter ones, although it doens' tlook as nice as the ones done only in the decapper/resizer.

So is that one die just useless to me right now then? Should it have something inside of it to guide the case in better??

btw- thanks a ton for the input guys!!