I *think* I finally beat this horse to death. I took all the great advice I got, cleaned off my bench, grabbed a handful of cases and started over.
I was resolved not to measure anything, and held true to that right to the very end.
Starting with a half dozen different cases I deprimed and sized them, ignored length, then successfully plunked them all in my case/ammo gauge.
The next step was to expand them, very minimally - only just enough that a coated cast bullet would sit unsupported in the mouth of the case without tipping over.
Gauge plunk test failed now, as expected, with the case only going in to the gauge about halfway. I realize this was a pointless test.
I then seated a bullet in the unprimed empty case to the length preferred by my magazines. The barrel will accept them longer but if they won’t load in the mags there’s no point.
I then tried to crimp and deflare the test rounds, but they caught in the crimp die and would only go in with a fast authoritative slam of the press ram.
After crimping none of the rounds would plunk in the gauge, some standing proud enough to display the entire rim and groove.
Here’s where I went back to the advice from Lee Precision. I got out my trusty Dremel and with a sandpaper cylinder proceeded to smooth the die entry cone and make a secondary taper at its inner edge. I followed this up by using a fine grey Dremel cylinder to polish both the cone and the secondary bevel.
Back to the bench to make five more empty test rounds without readjusting the expander die from the previous setting.
Wow! What a difference, all the test rounds slid easily in to the crimp die, comparatively like sliding them in to soft butter.
After getting the crimp die adjusted so the crimps were reduced to SAAMI spec all of the rounds plunked effortlessly in to the gauge.
All I can surmise is that there was enough force exerted by the seating die before polishing that it micro-bulged the cases enough that they would not plunk nicely.
So thanks again to everyone for all of your advice and for sticking with me through the evolution. I know at times we were getting frustrated with each other and it was great you did not give up on me.
My takeaways
I was expanding too much to begin with which exacerbated the issue. By over expanding short cases it brought things to the point that longer cases were belled ridiculously. If I set the expansion on a short case with the bare minimum needed to avoid shaving lead the long cases are still reasonable.
In the end the flare was a red herring, and a problem of my own making.
My reliance on measurements and numbers confounded the issue. Some times playing by ear is better.
When frustrated or lost it is time to clean the bench, throw away my notes and start over from square one. It’s not magic or rocket science.
You guys are great! I need to listen better and trust tribal knowledge more.
I’ll do a full run tomorrow and post the results. I am a little burned out tonight.
