I've had the same problem with 30-06 that I haven't yet taken enough time to try to figure out (I'm shooting more pistol at the indoor range). I use mixed brass, too.

It's been a while and didn't take notes because I had no problem before:

I didn't have any problems with the old Lee Hand Tools, which neck sized only.

Using the RCBS die set (adjusted to the shell holder) gave probs and I thought I'd solve it with a FL die, and I don't think that fixed anything. I've been meaning to study the problem in depth, and maybe bring it up here if I couldn't figure things out.

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