Brass question

[AK_Maine_iac]

I have been reloading for a few months now. Also reloaded for many years way back in the 60;s and 70's. Never ran across this before. I picked up a large amount of RP 30-06 brass. Trimmed it to length, tumbled, primed it. loaded up 50 of them. (Lee single stage press and Lee pace setter dies FL.)
They all chambered well in my T/C Encore. About half of them would not eject. The ejector would not grab the rim on the case.
I measured the case rims with a set of calipers. All of them was within the same specs. Cases where not stuck in the chamber.
I had tested them before i loaded them. They all worked fine.:banghead:

 

[popper]

Check them with a case gauge. Too short and they won't let the extractor hook.

 

[tightgroup tiger]

I agree,

I think you ran them to far into your resizing die and shortened the shoulder.