So...... I have brass that is 1.635 fireformed. Where it came from, what it was shot through, I have no idea. I have brass that was fireformed in my bolt action Rem 700 that measures 1.625. You are all saying that I should resize the brass to 1.625 - .001 to .002. I am on board with that. What I fear you are missing because I am not making it clear is that using my Redding Competition die this was not a problem. I was able to resize 200+ rounds of LC13 to exactly those numbers. I reread my OP and where I got 1.615 is still a mystery to me. After switching to a Forster die, I can't even get close. I'm not talking about +/- .002, I'm saying that I need to bump the brass back .010" to get it to 1.625 from 1.635. I used the ole Sharpie method of marking the neck and shoulder to see how far the case was going up into the die. Using that method, I determined that even when the neck was fully inserted into the die, there was no contact with the shoulder (the shoulder remained at the original 1.635 as measured with my Hornady headspace attachment to my digital caliper). In order to make contact with the shoulder to bump it back, let's forget about the number for a moment, the shoulder begins to deform, using my imagination it's as if the die is cut to some other "shape". I understand how the shoulder deforms during firing when there is excessive room to do so, and how a die then "reshapes" the shoulder to SAMMI specifications.
I have tried to google the difference between "competition dies" and standard FL dies and am still unclear. I'm definitely not saying or even thinking that this is the cause of my headache, I don't even know if there is a difference so how could I.
As for how I removed the stuck case...... I pulled the stem out as far as I could (the ball was being held by the neck I assume), drilled then tapped the case, inserted a 1/4-20 and bent the crap out of all of my made in china washers. Got online with Amazon Prime and they sent me a RCBS kit which I used to extract the brass...... that sumbitch was a mother to get out.
I replaced the stem and tried using the die but it got scratched somehow and is now leaving marks on the brass. I tried sourcing a replacement die but all I could find were sets. I tried running some lapping compound on a mop but it's still leaving marks. Thinking about asking if Redding can fix it.